1. business and industrial
2. energy
3. oil

Performance and problems of hydraulic pumps
in heavy agricultural machines in Sudan
by:
Haitham AbuSabah Elsamani
B.Sc. Agric. (Honours 2001)
University of Khartoum
A thesis Submitted to the University of Khartoum in Partial
fulfillment of the requirements for The degree of M.Sc. Agric.
Engineering
Supervisor:
Dr. Omer Mohammed Eltom
Department of agriculture Engineering
Faculty of agriculture
University of Khartoum
April (2004)
Words can never express my deepest appreciation and sincere
gratitude to my supervisor Dr. Omer Mohammed Eltom, one member of
the Department of Agricultural Engineering Faculty of Agriculture,
University of Khartoum for his enormous assistance, Professional
guidance, constructive useful criticism and encouragement throughout the
progress of this research.
Thanks are extended to all members of the Department of
Agricultural Engineering, Faculty of Agriculture for their cooperation.
Sincere gratitude is extend to my all friends colleagues and relatives who
assisted me in one way or another particularly Abu Bakr Bashir.
I owe spherical obligation to the general director of the Kharotum
State Ministry of Agriculture, general director of ElGazira Scheme,
general director of Jamda Company, and general director of Kennana
Sugar Company, for their financial assistance and support.
I am pleased to express my appreciation to all my family members,
special thanks due are to my uncle Abd ElGader Hassan &
FathElrahman Mohammed for their financial assistance and significant
support during this research.
I am indebted to my family members for their patience,
encouragement and moral support during this research.
Thanks are first and last to God (Alla). Who enabled me to conduct
this study by the grace of him and donated me strength and patience.
To - the soul of my father who
is still in my life
To - my mother who learn me
how to love my life
To - my family who struggled patiently
to lighten my way
To - my sisters, brothers and lovely
friends who enjoy my life with
endless love for life
Abstract
The increase of power price, spare parts, maintenance, highly advanced
technology development of hydraulic system, and other operating requirements were
the main reasons behind this study.
The study was conducted on three agricultural schemes Khartoum State
Ministry of agriculture, ElGazira Scheme, Kenana Sugar Company. The study
concentrated on the evaluation of performance of machines operated by hydraulic
systems in these schemes with reference to pump efficiency and hydraulic system
operation by operators.
A sample survey of three schemes Khartoum State Ministry of Agriculture,
ElGazira Scheme and Kennana Sugar Company was carried out. The samples were
randomly selected from the heavy machines in these schemes. The information about
machines performance, national companies, repair and maintenance, spare parts,
hydraulic operators, pumps types, delivery pressure, and power consumption were
collected.
The pumps were found to work at low efficiencies of 27 percent and 58
percent as average. This low pump efficiency could be due to many factors including
pump selection and installation procedure, condition of hydraulic pump (i.e. pump
delivery, pump age, maintenance, working hours and power type). Spare parts and
operator’s education level and skill were also considered as well as social factors. The
factors were studied for each pump and statistically analyzed using t-test, chi-square
and correlation coefficient techniques.
The analysis showed that pump selection and installation procedure, pump
age, maintenance, availability of spare parts, operator’s education level and skill and
land ownership significantly affected pump efficiency. Furtherly these pumps were
found to be installed at lower operation level than the recommended by their
manufacturers.
The amount of power consumed was significantly higher than that which
could have been consumed if these pumps were working at the assumed pump
efficiency of 60 percent and applying the required amount of hydraulic oil to do work.
Which can save about 50 percent of power with an expected increase in machine
yield.
‫ﺧﻼﺻﺔ اﻷﻃﺮوﺣﺔ‬
‫ﻇﺮوف ارﺗﻔﺎع أﺳﻌﺎر اﻟﻄﺎﻗﺔ‪ ،‬ﻗﻄﻊ اﻟﻐﻴﺎر‪ ،‬اﻟﺼﻴﺎﻧﺔ‪ ،‬اﻟﺘﻘﺪم اﻟﺘﻜﻨﻮﻟﻮﺟﻲ اﻟﻤﺘﻄﻮر ﻟﻸﻧﻈﻤﺔ اﻟﻬﻴﺪروﻟﻴﻜﻴﺔ‪،‬‬
‫واﺣﺘﻴﺎﺟﺎت اﻟﺘﺸﻐﻴﻞ اﻷﺧﺮى آﺎﻧﺖ ﻣﻦ اﻷﺳﺒﺎب اﻟﺮﺋﻴﺴﻴﺔ وراء إﺟﺮاء هﺬﻩ اﻟﺪراﺳﺔ‪.‬‬
‫أﺟﺮﻳﺖ هﺬﻩ اﻟﺪراﺳﺔ ﻓﻲ ﺛﻼﺛﺔ ﻣﺸﺎرﻳﻊ زراﻋﻴﺔ وزارة اﻟﺰراﻋﺔ وﻻﻳﺔ اﻟﺨﺮﻃﻮم‪ ،‬ﻣﺸﺮوع اﻟﺠﺰﻳﺮة‪،‬‬
‫ﺷﺮآﺔ ﺳﻜﺮ آﻨﺎﻧﺔ‪ .‬وﻗﺪ اﺧﺘﺼﺖ هﺬﻩ اﻟﺪراﺳﺔ ﺑﺘﻘﻴﻴﻢ أداء اﻵﻟﻴﺎت اﻟﺰراﻋﻴﺔ اﻟﺜﻘﻴﻠﺔ اﻟﺘﻲ ﺗﻌﻤﻞ ﺑﺎﻟﻬﻴﺪروﻟﻴﻚ ﻓﻲ هﺬﻩ‬
‫اﻟﻤﺸﺎرﻳﻊ ﻣﻦ ﻧﺎﺣﻴﺔ آﻔﺎءة هﺬﻩ اﻟﻤﻀﺨﺎت وﻣﻤﺎرﺳﺎت اﻟﻌﻤﻞ ﻓﻴﻬﺎ ﺑﻮاﺳﻄﺔ اﻟﻌﺎﻣﻠﻴﻦ‪.‬‬
‫ﻟﻘﺪ أﺟﺮﻳﺖ اﻟﺪراﺳﺔ ﻋﻦ ﻃﺮﻳﻖ أﺧﺬ ﻋﻴﻨﺔ ﻣﺴﺤﻴﺔ ﺗﺘﻜﻮن ﻣﻦ ﺛﻼﺛﺔ ﻣﺸﺎرﻳﻊ زراﻋﻴﺔ وهﻲ وزارة اﻟﺰراﻋﺔ‬
‫وﻻﻳﺔ اﻟﺨﺮﻃﻮم‪ ،‬ﻣﺸﺮوع اﻟﺠﺰﻳﺮة‪ ،‬ﺷﺮآﺔ ﺳﻜﺮ آﻨﺎﻧﺔ وﺗﻢ اﺧﺘﻴﺎرهﺎ وأﺧﺬ اﻟﻌﻴﻨﺎت ﻣﻦ هﺬﻩ اﻟﻤﺸﺎرﻳﻊ ﻋﺸﻮاﺋﻴًﺎ‪ .‬ﻓﻲ‬
‫هﺬﻩ اﻟﺪراﺳﺔ ﺗﻢ أﺧﺬ ﻋﻴﻨﺔ ﻣﺴﺤﻴﺔ ﻟﻤﻌﺮﻓﺔ أداء اﻵﻟﻴﺎت واﻟﺸﺮآﺎت اﻟﻌﺎﻟﻤﻴﺔ ﺑﻬﺎ‪ ،‬وإﺟﺮاءات اﻹﺻﻼح واﻟﺼﻴﺎﻧﺔ‪،‬‬
‫ﻣﺼﺎدر ﻗﻄﻊ اﻟﻐﻴﺎر‪ ،‬أداء ﻋﻤﺎل اﻟﻬﻴﺪروﻟﻴﻚ وأداء ﻣﻀﺨﺎت اﻟﻬﻴﺪروﻟﻴﻚ وآﻤﻴﺔ اﻟﻄﺎﻗﺔ اﻟﻤﺴﺘﻬﻠﻜﺔ ﻓﻲ وﺣﺪة اﻟﺰﻣﻦ‪.‬‬
‫دﻟﺖ اﻟﻨﺘﺎﺋﺞ ﻋﻠﻰ أن هﺬﻩ اﻟﻤﻀﺨﺎت ﺗﻌﻤﻞ ﺑﻜﻔﺎءة ﻣﺘﺪﻧﻴﺔ ﺗﺘﺮاوح ﺑﻴﻦ ‪ %27‬وﺑﻤﺘﻮﺳﻂ آﻠﻲ ‪ %58‬هﺬا‬
‫اﻟﺘﺪﻧﻲ ﻓﻲ آﻔﺎءة اﻟﻤﻀﺨﺎت ﻋﺰي ﻷﺳﺒﺎب آﺜﻴﺮة‪ ،‬ﺗﺸﻤﻞ ﻃﺮﻳﻘﺔ اﺧﺘﻴﺎر وﺗﺮآﻴﺐ هﺬﻩ اﻟﻤﻀﺨﺎت وﺣﺎﻟﺔ وﺣﺪة‬
‫اﻟﻤﻀﺨﺔ ﻓﻴﻤﺎ ﻳﺸﻤﻞ )ﺳﺮﻋﺔ اﻟﻤﻀﺨﺔ‪ ،‬ﻋﻤﺮ اﻟﻤﻀﺨﺔ‪ ،‬اﻟﺼﻴﺎﻧﺔ‪ ،‬ﺳﺎﻋﺎت اﻟﺘﺸﻐﻴﻞ اﻟﻴﻮﻣﻲ‪ ،‬وﻧﻮع اﻟﻄﺎﻗﺔ اﻟﻤﺴﺘﻌﻤﻠﺔ(‬
‫هﺬا ﺑﺎﻹﺿﺎﻓﺔ إﻟﻰ ﺗﻮﻓﺮ وﻧﻮﻋﻴﺔ ﻗﻄﻊ اﻟﻐﻴﺎر‪ ،‬اﻟﻌﻮاﻣﻞ اﻻﺟﺘﻤﺎﻋﻴﺔ وﻧﻮﻋﻴﺔ ﻣﻠﻜﻴﺔ اﻷرض‪ .‬هﺬﻩ اﻟﻌﻮاﻣﻞ ﺗﻤﺖ‬
‫دراﺳﺘﻬﺎ ﻓﻲ آﻞ ﺁﻟﺔ ﻣﻦ هﺬﻩ اﻟﻤﺸﺎرﻳﻊ وﺗﻢ ﺗﺤﻠﻴﻠﻬﺎ إﺣﺼﺎﺋﻴًﺎ ﻟﻤﻌﺮﻓﺔ ﺗﺄﺛﻴﺮهﺎ ﻋﻠﻰ آﻔﺎءة هﺬﻩ اﻟﻤﻀﺨﺎت ﺑﺎﺳﺘﻌﻤﺎل‬
‫اﺧﺘﺒﺎرات )‪ (t-test‬وﻣﺮﺑﻊ آﺎي )‪ (chi-square‬وﻣﻌﺎﻣﻞ اﻟﻌﻼﻗﺔ )‪.(techniques correlation coefficient‬‬
‫ﻧﺘﺎﺋﺞ اﻟﺘﺤﻠﻴﻞ أوﺿﺤﺖ أن ﻃﺮﻳﻘﺔ اﺧﺘﻴﺎر وﺗﺮآﻴﺐ اﻟﻤﻀﺨﺔ‪ ،‬ﻋﻤﺮ اﻟﻤﻀﺨﺔ‪ ،‬اﻟﺼﻴﺎﻧﺔ ﺗﻮﻓﺮ ﻗﻄﻊ اﻟﻐﻴﺎر وﻣﺴﺘﻮى‬
‫ﺗﻌﻠﻴﻢ اﻟﻌﺎﻣﻠﻴﻦ وﺧﺒﺮاﺗﻬﻢ ﻟﻬﺎ ﺗﺄﺛﺮات ﻣﻌﻨﻮﻳﺔ ﻋﻠﻰ آﻔﺎءة هﺬﻩ اﻟﻤﻀﺨﺎت‪ ،‬ﻓﻘﺪ وﺟﺪ أن هﺬﻩ اﻟﻤﻀﺨﺎت ﻟﻢ ﺗﺘﺒﻊ‬
‫اﻟﺘﻮﺻﻴﺎت اﻟﻤﻮﺻﻰ ﺑﻬﺎ ﻣﻦ ﻗﺒﻞ اﻟﺸﺮآﺎت اﻟﻤﺼﻨﻌﺔ ﻟﻬﺬﻩ اﻟﻤﻀﺨﺎت‪.‬‬
‫آﺎﻧﺖ آﻤﻴﺔ اﻟﻄﺎﻗﺔ اﻟﻤﺴﺘﻬﻠﻜﺔ ﺗﻔﻮق ﺑﻔﺮق ﻣﻌﻨﻮي اﻟﺤﺎﺟﺔ اﻟﻔﻌﻠﻴﺔ ﻟﻠﻮﻗﻮد‪ .‬ﻓﺈذا اﺳﺘﻄﺎع اﻟﻤﻬﻨﺪس أو اﻟﻌﺎﻣﻞ‬
‫اﺳﺘﻌﻤﺎل اﻟﻤﻀﺨﺔ ﻓﻲ آﻔﺎءﺗﻬﺎ اﻟﻘﺼﻮى ‪ %60‬ﻟﺘﻌﻤﻞ ﻓﻘﻂ ﻟﻼﺣﺘﻴﺎﺟﺎت اﻟﻔﻌﻠﻴﺔ ﻓﻲ أداء اﻟﻌﻤﻠﻴﺎت اﻹﻧﺘﺎﺟﻴﺔ ﻓﺈن أآﺜﺮ‬
‫ﻣﻦ ‪ %50‬ﻣﻦ اﻟﻄﺎﻗﺔ اﻟﻤﺴﺘﻬﻠﻜﺔ ﻳﻤﻜﻦ ﺗﻮﻓﻴﺮهﺎ ﻣﻊ ﺗﻮﻗﻊ ﻓﻲ زﻳﺎدة إﻧﺘﺎج اﻵﻟﺔ‪.‬‬
List of contents
Subject
Page
Dedication
і
Aknowledgments
ii
Abstractc (English)
iii
Abstractc (Arabic
v
List of contents
viii
List of figures
ix
List of tables
x
Chapter one (1):
Introduction
1
Chapter two
Literature Review
2.1 Machines in agricultural production………………… 3
2.2 Mechanization in Sudan………………………………… 4
2.3 Power Sources in agriculture………………………… 4
2.4 Hydraulic control…………………………………..… 5
2.5 Hydraulic Systems for farm Equipment…………….… 5
2.6 Fundamentals of hydraulics ………………………… 6
2.7 Hydraulic Symbols …………………………………… 7
2.8 Types of hydraulic systems…………………………… 7
2.9 Basic principles of hydraulics ………………………… 9
2.10 Hydraulic used in Farm equipment ………………….. 10
2.11 special hydraulic system …………………………….. 10
2.12 Mounted equipment hydraulic control systems ……… 11
2.13 Selecting hydraulic oil ……………………………….. 12
2.14 Hydraulic energy ……………………………………… 13
2.15 Hydraulic system components …………………………14
2.16 Hydraulic pumps ……………………………………… 14
2.17 Principle of hydraulic pumps ………………………… 15
2.18 Types of hydraulic pumps …………………………… 15
2.19 Pump Selection ……………………………………….. 23
2.20 Classification of pump types…………………………. 23
2.21 Hydraulic Power Selection …………………………… 24
2.22 Hydraulic horse power ……………………………… 24
2.23 Malfunction of pumps ………………………………… 24
2.24 Effective of contaminated fluid ………..…………….. 25
2.25 Effective of Improper fluid to pump ………………… 26
2.26 Pump maintenance …………………………………… 27
2.27 Diagnosing pump failures …………………………
Chapter three
Material and method
3.1. Site description …………………………………….
3.2. Data collection …………………………………….
3.2.1 Data from questionnaire …………………………..
3.2.2 Parameters calculations……………………………….
3.3. Power Consumption ………………………………..
Chapter four
Results and Discussions
4.1. Actual pump efficiency …………………………….
4.2. Factors affecting pump efficiency ………………….
4.2.1 Condition of Hydraulic pump …………………….
4.2.2 Spare parts and hydraulic pumps and
specified tool of Diagnosis ……………………….
4.2.3 Machine relationship …………………………….
4.2.4 Operator’s skill and training………………………
4.2.5 Land ownership… …………………………………..
4.3 Power consumption ………………………………..
4.3.1 Fuel consumption ………………………………….
4.3.2. Oil consumption …………………………………..
Chapter Five
Conclusion and recommendations ………………………..
References …………………………………………
Appendix ………………………………………….
27
29
30
30
30
31
33
37
38
44
46
48
51
51
52
55
58
61
64
List of figures
Figures
page
2.1- Types of hydraulic pump on basis of oil circuits …….. 17
2.2- Types of hydraulic pump on basis of design… ……….. 18
2.3- Types of hydraulic pump on basis of use and oil pressure 19
2.4- Types of hydraulic pump on basis of use and oil pressure 20
2.5- External Gear pump …………………………………. 21
2.6- External pump in operation …………………………. 21
2.7- Internal Gear pump ………………………………….. 21
2.8- Internal Gear pump in operation …………………….. 21
2.9- Balanced Vane pump ………………………………… 21
2.10- Balanced Vane pump in operation ………………….. 21
2.11- Reciprocating piston pump ………………………… 22
2.12- Inline Axial piston Pump variable Displacement ….. 22
2.13- Inline Axial piston pump in operation ……………… 22
2.14- Servo Device in operation. Tilting Swashplate …… 22
2.15- Broken pump drive shaft – fitigue failure from
Too – Tight drive belts. ……………………………. 24
2.16- Pump pistons Scored by Contaminated Fluid ………. 25
2.17- Vane pump rotor ring worn and pitted by
contaminated fluid …………………………………. 25
2.18- Vane pump rotor damaged by contaminants in fluid … 26
2.19- Vane pump ring wear from use of Improper fluid …… 27
4.1- The relationship between pump age and pump efficiency 40
4.2- The relationship between working hours and
pump efficiency ……………………………………… 43
4.3- The relation ship between machine ownership
and pump efficiency ………………………………….. 47
4.4- The relation ship between hydraulic operator’s
skill and pump efficiency ………………………… … 50
List of table
Table
page
4.1- The means of the main information of pumps on
Khartoum state Ministry of agriculture, Gezira scheme,
kenana sugar company ………………………………..
35
4.2- Minimum, maximum, mean and standard deviation
of pump efficiency from Khartoum state ministry of
agriculture, Gezira scheme, kenana Sugar company ….
36
4.3- T- value for the difference between mean pump
efficiency and assumed (60%) efficiency ………………… 36
4.4- The efficiency of pump delivery on pump efficiency… 39
4.5- The effect of maintenance frequency of
pump efficiency ………………………………………
41
4.6- The effect of the type of power (oil, fuel) on
pump efficiency …………………………………..
44
4.7- The effect of availability of spare parts on
pump efficiency …………………………………...
45
4.8- The effect of quality of spare parts on pump efficiency 45
4.9- The effect of specified tool of diagnosis on
pump efficiency……………………………………… 46
4.10- the effect of hydraulic operator’s work
on pump efficiency ………………………………… 48
4.11- the effect of operator’s education level
on pump efficiency ………………………………… 49
4.12- the effect of land ownership on pump efficiency
51
4.13- Average number of working hours and the
corresponding fuel consuption “F1” existing practice
and efficiency , “F2” low efficiency , “F3” optimum
efficiency …………………………………………… 53
4.14- T-value for the difference between F1 and F2 ……… 54
4.15- T-value for the difference between F2 and F3 …….. 54
4.16- T-value for the difference between F1 and F3 ………. 54
4.17- Average number of working (hours per day)
and cores pording oil O1 existing practice and
efficiency, “O2” low efficiency, “O3” optimum efficiency 56
4.18- T-value for the difference between O1 and O2 ……… 57
4.19- T-value for the difference between O2 and O3 ……… 57
4.20- T-value for the difference between O1 and O3 ………
57
CHAPTER ONE
INTRODUCTION
The use of machines in agricultural production, has been one of the
output – standing developments in Global agricultural during the past
century. The results of the application are to be seen in many aspects of
human life , as million of workers to be released to other activities in
developed countries.
Agricultural production need further modern mechanization control system
due to shortage in labour and increase in wages coupled with large horizontal and
vertical expansion of agricultural production in different areas and that is found in
hydraulic control system.
Hydraulic control system is basically a method of transmitting power from
source to the machine or component being operated, in addition to providing
convently located and easy operated control levers. The medium that used to transmit
the power in hydraulic system is fluid that is contained by the lines between the driver
and driven members, the heart of hydraulic system which creates the flow of fluid
which supplies the whole circiut is the pump.
The study concerns with hydraulic system pump in heavy agricultural
machines in three agricultural schemes (often referred to Khartoum, Gezira, and
Kenana schemes )that had different climate and management conditions. Accordingly,
all the present performance problems and efficiency of machines in this schemes. The
increase of power price (fuel&fluid), spare parts, maintanance and operating cost,
showed that the increase of cost of agicultural inputs compared with value output are
not ecouraging. The power cost consumption was directly affected by improper use of
these pumps.
The study of the performance and problems of hydraulic pumps in heavy
agricultural machines is with the following objectives:
1)
The study of pump efficiency and factors affecting it.
2)
Power consumption with respect to pump efficiency and work
applied.
Chapter two
Literature Review
2.1 Machines in agricultural production
The constant expansion of world population is continuously
demanding an ever –increasing agricultural production in form of food
and fiber. Resourceful farm management is becoming a major
consideration in today’s turbulent economic climate. Efficiency
mechanization is one of the means to increase crop production, with the
following advantage:
ƒ
Minimizing high peak labour demand that occurs relatively over short
periods of times each year as in, planting, cultivating and harvesting cereal
crops.
ƒ
Encouraging better management of farm enterprise and providing more
free time for planning and study
ƒ
Contributing to timeliness that increases productivity. Many field
operation must be performed with in rather short periods of time, if
operation results or maximum returns are to be obtained.
ƒ
Improving the working conditions and performance of jobs that should
otherwise be difficult or impossible manually.
ƒ Reducing of over all cost as a result of mechanization is highly desirable
but not always imperative.
However the history indicates that the process of mechanization is
dynamic, with no ultimate goal in sight. Each manufacturer must
continuously improve his products and develop new aspects (Abd alla,
2000).
2.2 Mechanization in Sudan
Mechanical was first introduced in agriculture of establishment of
Sudan, during the early (1920s), at the time of establishment of Sudan
production syndicate, which had pioneered the use of plow tackle unit
consist of two 60hp engines pulling combined cultivator or multiple
ridger. Later in mid- 1940s, the increased use of machinery was
associated with the need to produce more food, during the Second World
War. At that time a50hp tractor and wide – level disk harrows with seeder
box were introduced. By 1950s, the private sector had started to invest
money in machinery. This has lead to horizontal expansion policy, and
the opening up of a new agricultural land in conjunction with greater use
of machinery (Abd Alla, 2000).
2.3 Power sources in agriculture
Power sources in agriculture are one of the determining factors of
the level of agricultural development and stage of mechanization. There
are three types of power used in cultural practices-human power, animal
power, and motorized power (Fashina, 1986).
Human power is used in traditional farming through hand tool in
all cultural practices from land preparation to harvesting mainly in small
areas. Human power considered as essential source of power for more
than 80% of the farmers in West Africa, it has many disadvantages like
low crop production limiting the cultivable land and low returns (MOA,
1991). There are many types of hand tool for different cultural operations
e.g. hoe. For weeding, “toria” for sowing and panga for cleaning these
tools usually made of wood or iron or both.
Animal power is used in agricultural practices through draft
implements e.g. ploughs, seeders, and carts. Animal draft implements can
be manufactured locally from scrap material, which makes it cheap and
available (Fashina, 1986).
Tractor power is used under certain conditions and always
unavailable for rural societies because of small size lack of technical
awareness and high cost of its use, moreover, tractors are not available in
most cases in rural areas (Bansal, 1992). But tractor played large
contribution as a source of power in modern areas. Tractor power is
delivered to implements in four ways the draw bar, the belt pulley, the
power take of, the power lift, or hydraulic control (Barger, 1961).
2.4 Hydraulic control
Hydraulic control described by Smith (1976) is basically the
method of transmitting power from the power source to machine or
component being operated.
Hydraulic control system, in addition to providing conveniently
located and easily operated control lever are extremely flexible in regard
to application possibilities cylinders may be built into the tractor, on
external cylinders may be mounted in various positions on the tractor on
trailed implement (Bainer, 1955).
Hydrostatic, or the mechanics of fluids, was defined by Blasise
Pascal (1653), as follows:
Pressure applied to an enclosed fluid is transmitted equally and
undiminished in all directions to every part of fluid and of its restraining
surfaces.
2.5 Hydraulic systems for farm equipment
Farm equipment prior to the nineteenth – century era was animal –
drawn, guided by hand, and lifted manually. Later, when equipment was
mounted on wheel, levers were used to raise and lower the working units
as described by Smith (1976), that is:
The first mechanical power lift was developed for the trailing type
tractor-drawn plows about 1910. The tractor power lift was developed
about 1930 to raise and lower planters and cultivators mounted on the
row-crop tractor. The use of hydraulic power for lifting tractor-mounted
equipment was introduced in 1935. Hydraulic power lift are now used for
raising, lowering, and controlling almost all types of field equipment,
ranging from the small plow to the platform of grain combine and the
drums of cotton- picking.
Hydraulic controls as explain by Bainer (1955) are the: mechanical
power lifts on tractors were introduced commercially in the late 1920’s
following the advent of mounted cultivators and general –purpose tractor.
Hydraulic lifts of mounted implement appeared few years later, and in the
early 1940’s hydraulic controls for trailed implements were adopted.
Since that time, the development of hydraulic control system has been
raped. Electric and pneumatic power lift have been employed on only
limited extend.
Hydraulic mechanisms have been used as reported by Hunt (1973)
in farm machinery since about (1935). The first production of hydraulic
lift for tractor was introduced by Deere & Co. In (1939), Harry Ferguson
and Henry Ford introduced tractor which use hydraulics to sense the draw
bar pull of the implement and transfer.
2.6 Fundamentals of hydraulic:
The fundamental law of hydraulic as written by Smith (1976) is
that force of (1Ib) acting on area of (1in2) can be used to lift weight of
(10Ib) if the area under the weight is (10in2). In metric units, force of
(454g) acting on (6.45cm2) could be used to lift a weight of (4540g) if the
weight had an area of (64.5cm2).
2.7 Hydraulic symbols
Hydraulic symbols reported by Liljedahi (1979) are that hydraulic
system have became so complicated that it is much easier to used
symbols to describe them. Graphic symbols for fluid power diagrams,
must necessary be learned before proceeding to discussion of hydraulic
system.
The following list describes some of the advantages of using
symbols:
•
Their use simplifies publication of hydraulic circuits.
•
Complicated circuit can be tried out by using stock
hydraulic component “abroad board”.
•
•
Symbols save drawing time.
Symbols can be used to convey the functional requirements of
component, or an assembly of components, to design engineers
without actually telling them how it must look.
2.8 Types of hydraulic systems
There are two types of hydraulic systems as described by
Jones(1966) that is:
•
Closed –center, constant-pressure system because no oil is
pumped unless there is demand for it from one of hydraulic
mechanisms, and when the operating valves control the hydraulic
mechanisms are in the neutral position, there is no flow of oil
through these valves. It is a constant –pressure system for the
reason that with the engine and pump running constant pressure of
(2.300Ib.per sq) is maintained in the system.
•
The open-center system pumps oil constantly through the
hydraulic –mechanism operating valve and returns it to the
reservoir.
The advantages and disadvantages of close system:
The following list described some of the advantages and
disadvantages of closed-center hydraulic system:
The advantages of closed –center are:
•
Simpler valving and circuits in the case of multiple uses.
•
Simpler furthering control and instant response without
waiting for pressure build up.
•
Lower peak power requirement than in the open center
system.
The disadvantages of closed –center are:
•
All oil is pumped at high pressure although only small
proportion of the usage may require the pressure.
•
Valve must seal against the full pressure at all time to
avoid vesting energy.
•
Either variable-displacement pump or fixed displacement
pump with unload valve and accumulator is required, compare to
the only fixed in open, according to Lehann and Richey (1966).
2.9 Basic principles of hydraulics
The basic principles of hydraulics are few and simple as explained
by Deere (1979). The liquids have no shape of their own because of this
oil will flow into passage of any size or shape. Liquid will compress
slightly under pressure also its transmit applied pressure in all directions
and liquids provide greater increases in work force. This principle helps
to stop a large machine by pressing a break pedal.
Basic oil circuits as described by Bainer (1955) that the rated oil
pressures in early hydraulic system were (300psi) pressure high as
(3000psi) which are now used to limited extend, but the present trend is
towards rated pressure in the range of (800 to 1200 psi).
The extensive use of hydraulic lifts and controls makes it essential
that the operator of modern farm equipment should have an
understanding of the fundamental principles of power –lift hydraulic,
(Smith, 1976).
A system or design never malfunctions if operates exactly the way
you designed or built it. The struggle results from trying to make the
design, the operating conditions and the objectives compatible with one
anther. Hydraulic system have become so complicated that it is much
easier to use symbols to describe them, (Liljedahi, 1979).
2.10 Hydraulic used in farm equipment
Hunt (1973) reported that hydrostatic drives were first used in farm
equipment. He said that no development were by made the Case company
which inserted
a rogue converter into tractor’s drive line and by
international harvester which first used hydrostatic drives in farm
equipment .Since initial applications, hydraulic have been used to aid in
the control of steering , braking, clutching, speed changing, and power
transmission .
2.11 Special hydraulic system
Some late models of tractors, which have hydraulic powered brakes
and steering as well as implement control, are equipped with a hydraulic
system, which is specially designed to supply the power for these
different operations in the most efficient, and convenient manner,
described by Jones (1966).That is consists of main pump, power steering ,
power brakes, hydraulically operated rocker shaft, one or two selective
control valves to operate remote hydraulic cylinders, transmission pump,
and an oil cooler. These components connected together and supplied
with oil from a common reservoir the transmission assures adequate
circulation of oil to the transmission part .The same oil which operates
the hydraulic mechanisms lubricates the transmission and differential
gears. It also changes and cools the main pump and routes the oil to the
cooler to maintain proper oil temperature, this system is known as a
closed center.
2.12 Mounted equipment hydraulic control systems
Loader, bulldozer, backhoes (excavator), and fork lift are usually
mounted on the machine which propels them. Often they are sold as
custom units for a single job for easy control; hydraulics is widely used to
operate the mounted equipment. Deere, (1979) explain that in the
following:
•
Loader hydraulic system:
Most loaders are mounted on the front wheel or crawler tractor
which has it own hydraulic system, an open center type. Most loaders
have two kinds of control (raise and lower boom, dump and retract
bucket).
•
Bulldozer hydraulic system:
The bulldozer usually mounts on the front of crawler tractor for
greater traction in loose dirt. Most bulldozers have three types of blade
control (raise and lower, angle right and left, and tilt side to side on some
bulldozers). All three are controlled by hydraulic. On other only one or
two.
•
Backhoe(excavator)hydraulic system:
The back hoe is used for digging trenches. It usually mounts on the
rear of an industrial tractor such as a loader or bulldozer. The operator
controls the backhoe by mean of levers. These levers direct oil through
control valve to the proper cylinder to operate the boom, bucket, crowd,
or stabling functions (with double acting cylinder, special swing cylinder
used to rotate the boom.
•
Forklift hydraulic system :
The forklift is used to handle, and lift and stack products and
materials, many forklifts are mounted on the rear of a wheel tractor. The
tract is then operated in reverse, the operator facing the forklift. Most fork
lift have three types of hydraulic control (lift and lower the fork, tilt the
mast fore, and to shift mast from side -to- side (optional).
2.13 Selecting hydraulic oil
Hydraulic oil for tractors are used for two purposes operating the
hydraulic implement control system, and operating the hydraulic steering
mechanism. Although there are four kinds of oil used the single- grade
and multi-grade crankcase oils of various types, gear oil, hydraulic oil,
special oil, supplied by tractor manufacturers for use with their particular
tractor.
With any of the oil the designer of a machine takes into account the
effect the oil have on rubber seal or other rubber part in the hydraulic
system. Some tractor use oil from the transmission gear case, but even
tractors with an entirely independent hydraulic system are designed to use
a particular oil (SAE, 1964).
2.14 Hydraulic energy
Hydraulic energy is transmitted in two ways:
In the hydrodynamic system force is transmitted by high velocity
fluid flow hydrokinetic system, and the kinetic system of the fluid does
work when it is decelerated by mechanism such as turbine wheel. A
hydraulic system that transmits energy primarily by pressure is called a
hydrostatic systems, but all hydraulic systems used in farm machinery are
hydrostatic (Hunt, 1973).
The average annual energy requirements for the proposed work of
tractor must be known before an optimum power level can be selected,
field operation energy can be estimated for any given farm from the
performance of an existing implement (Hunt, 1979).
Fluid computed described by Hunt (1973) that:
Pressure is the indicator of potential energy of the system at any point.
Compute this pressure used this equation:
P=
F
A
where:
P: is the pressure, (psi)
F: is the force in (Ibs)
A: is the area of force in contact with the fluid, in2.
But the flow fluid in a system is described by the relation:
Flow= fluid displacement per unit time. Although flow expressed in gallons per
minute and it is computed as equation:
Q= 3.12 AV
Where:
Q: is the flow rate, gal/min.
A: is the cross-sectional area associated with the internal diameter of the conduit, in2.
V: is the average velocity of the fluid across the section ft/sec.
2.15 Hydraulic system components:
Hydraulic system components were classified by Hunt (1973) as:
The reservoirs are important components in the hydraulic system, cooling of
the fluid, separation often of entrapped gases, and the settling out and filtering out dirt
and metal particles are accomplished at the reservoir. The heat of hydraulic systems is
the pump.
The two basic components, in all hydraulic system reported by Smith (1976)
include the pump that converts the power from the engine to fluid power and the
actuator, such as a cylinder or motor, that converts the fluid power to the motion and
action that are being performed. Other parts of the system include the reservoir, lines,
connections, filters, and various types of valves.
A hydraulic system will consist of part or all of the following parts or
components as classified by Barger (1951) that is the pump, motor, valves line,
coolers, sump (supply tank), accumulator stored energy, controls (manual or
automatic). But Liljedahi (1979) classified the components as: pump, motor, valves,
lines, coolers, sump supply tank, accumulator stored energy, controls (manuals or
automatic), fluid, actutors, filters.
2.16 Hydraulic pumps:
The hydraulic pump is the heart of the hydraulic system, moves fluid and
induced fluid to work, as defined by Deere (1979) that pump convert mechanical
force into hydraulic fluid power.
Keppner (1978), said that the pump is often referred to as the heart of the
system. Pump similar to motor reported by Barger (1967) & Liljedahi (1979) that the
most simple type of pump or motor is a hydraulic cylinder, common method of
control on a hydrostatic transmission.
Pump is usually driven directly by the engine of the tractor or the selfpropelled machine, engine driven pumps operate continually and provide what is
commonly referred to as “live hydraulic system” (Kepner, 1978).
2.17 Principle of hydraulic pumps:
Smith (1976), explained that all pumps that create flow operate on principle of
displacement which can be done in two ways:
o Fixed- displacement (usually be driven in either direction without making
changes with in the pump).
o Variable- displacement (the eccentric housing can be moved in relation to the
rotor while in operation).
All pumps used in the hydraulic system are referred to as positive
displacement type, this means that the pump is designed to pump the same
volume of fluid over a wide range of pressure according to Kepner (1978), that
all pumps create flow they operate on principle called displacement.
Displacement can be done in two ways:
o Non- positive displacement, it simply picks up fluid and moves it “old water
wheel”.
o Positive displacement picks up fluid and moves it circuit “hydraulic pump”.
2.18 Types of hydraulic pumps
Most pumps used on today’s machines are categorized according to three
basics: (oil circuits, design, and use and oil pressure).
Bainer (1955), categorized on basis of oil circuits as:
-
Piston pumps are generally employed when rated pressures are greater than
1500 Psi.
-
Gear pumps are most common for pressures below this.
-
Vane-type pumps are also used to some extent between them (fig. 2.1).
Smith (1976) & Deere (1979), categorized it in basis of design as:
-
Gear pumps (External, Internal Gear pumps).
-
Vane pumps (Balanced, unbalanced vane pumps).
-
Piston pumps (Axial usually two types “Inline & bent axis”, Radial operate in
two ways “rotating cam and rotating piston” (fig. 2.2, 2.5, …, 2.14).
Barger (1951) & Liljedahi (1979) categorized it on the basis of use and oil pressure
as:
-
Radial piston pumps can be used as motors displacement can be controlled by
allowing the pressure to lift the pistons off the eccentric.
-
A spur-gear pump is normally used on tractor hydraulic systems of low
pressure.
-
The spur-gear, the internal-gear pump used in grerotor.
-
Vane- type pump, are all used on tractor hydraulic system where lower
pressures are used (fig. 2.3).
But the difference between Barger & Liljedahi in that is normally spur gear
pump is not used in tractor hydraulic system because it’s design will not
accommodate
the
higher
pressures
required,
although it can be used for pressure operation such as for charging a hydrokinetic
transmission etc (fig. 2.4).
Fig. 2.5- External Gear Pump
Fig.2.6 External Gear Pump in operation
source: Deere (1979)
Fig. 2.7- Internal Gear Pump
source: Deere (1979)
Fig. 2.9- Balanced Vane Pump
source: Deere (1979)
source: Deere (1979)
Fig. 2.8- Internal Gear Pump in Operation
source: Deere (1979)
Fig. 2.10- Balanced Vane Pump in Operation
source: Deere (1979)
Fig. 2.11- Inline Axial Piston Pump-
Fig.2.12- Reciprocating Piston Pump
Variable Displacement
source: Deere (1979)
source: Deere (1979)
Fig. 2.13- Inline Axial Piston Pump in Operation
source: Deere (1979)
Fig. 2.14- Servo Device in Operation. Tilting Swashplate
source: Deere (1979)
2.19 Pump Selection:
There are secondary factors judging pumps and pump applications such as
explained by Bainer (1955), that pump selection depend on basis of rated oil pressure
in hydraulic system.
Israelsen and Hansen (1962) reported the features other than efficiency to be
considered in selecting pump unit as brake horse power, availability and cost,
dependability and durability of unit, depreciation, profitability, maintenance and
convenience of operation, labour availability and quality, and effective utilization of
fluid.
James (1988) explained that economic is a primary criterion for selecting the
most suitable pump to get an efficient, profitable, and reservoir adapted for particular
condition of operation.
Molina (1993) reported that head-capacity at optimum operating point need to
be determined.
2.20 Classification of pump types:
Hydraulic pumps rated in a number of different ways based upon the amount
of fluid.
Rated oil pressures in early hydraulic system were sometimes as low as (300
psi) pressures and as high as (3000 psi) are now used to limited extent, but the present
trend is toward rated pressures in the order of (800 to 1200 psi), in multiple-cylinder
rated pressures are greater than about (1500 psi), (Bainer, 1955).
Common units to designate the output flow include gallon per minute or liters
per minute the flow rate is determined not only by speed (r/min) at which the pump is
being turned, but also by the physical size of the pump. Also are rated according to
volume, pump displacement and the units are generally measured in cubic inches,
Cubic centimeters, gallons, or liters. Pumps used on farm machinery usually range in
size from 10 g/min (38 liters/min.) to 50 g/min (190 liter/min), accordance to Smith
(1976).
Deere (1979) have discussed some of the factors used in evaluation and
classification of pump types such as physical size, pump delivery, pump pressure,
pump speed, and pump efficiency.
2.21 Power selection:
The selection of type of power unit to operate the pump depends on some
factors reported as by Schwab (1966) that the amount of power required initial cost,
availability and cost of fuel or electricity, annual use, and duration and frequency of
pumping.
2.22 Hydraulic horse power:
The pressure and flow outputs from pumps define the pumps hydraulic horse
power out put as stated by Hunt (1973) in the following equation:
H .P =
PQ
1714
where:
P: pressure. Psi
Q: flow rate as pumps are rated as delivering certain flow gal/min
2.23 Malfunction of pumps:
The majority of hydraulic pump failure is due to human factor such as poor
maintenance, bad repair, exceeding operating limits, the greatest cause- the usual fluid
which is dirty or of poor quality. But to prevent failure one should know, maintain the
hydraulic system, operate it as designed, use the proper fluids this accordance to
Deere (1979).
Fig. 2.15- Broken pump drive shaft – Fatigue failure from too-tight drive belts
source: Deere (1979)
2.24 Effective of contaminated fluid:
Hydraulic oils must be matched with the hydraulic system design. One reason
is that the type of hydraulic pump selected by the manufacturer is related to the
viscosity of oil used according to (SAE, 1964).
Deere (1979), stated that affective of contaminated fluid in some components
of pump such as pump piston scored by contaminated fluid, vane pump rotor damaged
by contaminated fluid, abnormal wear created by sludge in vane rotor ring (fig. 2.16,
2.17, 2.18).
Fig. 2.16- Pump Pistons Scored by Contaminated Fluid
source: Deere (1979)
Fig. 2.17- Vane Pump Rotor Ring Worn and Pitted by Contaminated Fluid
source: Deere (1979)
Fig. 2.18- Vane Pump Rotor Damaged by Contaminants in Fluid
source: Deere (1979)
2.25 Effect of improper fluid to pump:
There are some of thing that may occur if the fluid viscosity is wrong that
SAE (1964) stated that if you use a heavier oil, there may be excessive heating which
in turn causes rapid oil oxidation (oil thickening) which further increases its viscosity.
This causes gummy deposits to accumulate on pump and valve and heavy sludge to
form and settle in low points of hydraulic system
If you the oil is too light, temperatures may go up due to loss of pump
efficiency losses from leakage are more likely to occur.
Hunt (1973), explained that internal leakage in the pump between the piston
and the cylinder, between gear teeth and the pump housing, or around vanes limits the
working pressure obtained from pumps, although some leakage is necessary to
lubricate the pumps.
Deere (1979), reported that if the fluid is too light both internal and external
leakage will increase, pump slippage will increase which cause heat and reduce
efficiency, part wear will increase for lack of adequate lubrication, system pressure
will be reduced overall control of the system functions will be spongy.
If the fluid is too “heavy” the Internal friction will increase, which in turn will
increase flow resistance through the system; temperature will increase, thus increasing
the chance of sludge build up; operation of functions will be sluggish and erratic;
pressure drop throughout the system will increase; more power will be required for
operation (fig. 2.19).
Fig. 2.19-Vane Pump Ring Wear from Use of Improper Fluid
Source: Deere (1979)
2.26 Pump maintenance:
The regular maintenance of any machine including pumps is of great
importance for increasing its efficiency and prolonging it’s working life. Michael
(1978), stated that for safe and efficient operation of pump, lubrication of different
parts should be carried out strictly according to manufacture’s instructions.
2.27 Diagnosis of pump failures:
There are much failure occur to the hydraulic pump, but some failures diagnosed
by Deere (1979), that is:
-
Pump doesn’t deliver fluid:
ƒ
Fluid level in reservoir is too low.
ƒ
Pump inlet line plugged.
-
No pressure:
ƒ
Pump not delivering fluid.
ƒ
Vane in vane pump slicking.
-
Low erratic pressure:
ƒ
Cold fluid.
ƒ
Fluid viscosity wrong.
-
Low on erratic pressure-continued:
ƒ
Leak on restriction at inlet line.
ƒ
Pump speed too low.
-
Pump making noise:
ƒ
Low fluid level.
ƒ
Air in the system.
-
Excessive wear:
ƒ
Abrasive contaminators on sludge in fluid.
ƒ
Viscosity of fluid too lower or too high.
-
Excessive fluid leakage:
ƒ
Damage seals or package around drive soft.
-
Internal rates breakage:
ƒ
Excessive pressure above maximum limits for pump.
ƒ
Seizure due to lack of fluid.
Chapter Two
Literature Review
Mechanical in Sudan
Mechanical was first introduced in agriculture of abolishment of
Sudan, during the early (1920s), at the time of establishment of Sudan
production syndicate, which had pioneered the use of plow tackle unite
consist of two 60hp engines pulling combined cultivator or multiple
ridger.
Later in mid- 1940s,the increased use of machinery was associated
with the need to produce more food, during the Second World War. At
that time a50hp tractor and wide – level disk harrows with seeder box
were introduced. By 1950s,the private sector had started to invest money
in machinery. This has head to horizontal expansion policy, and the
opening up of anew agricultural land in conjunction with greater use of
machinery (Abd Alla, 2000).
Power sources in agriculture
Power sources in agriculture are one of the determining factors of
the level of agricultural development and stage of mechanization. There
are three types of power used in cultural practices-human power, animal
power, and motorized power (Fachina, 1986).
Human power is used in traditional farming through hand tool in
all cultural practices from hand preparation to harvesting mainly in small
areas. Human power considered as essential source of power for more
than80% of the farmers in west Africa, it has many disadvantages like
low crop production limiting the cultivable land sand and low returns
(MOA, 1991). There are many types of hand tool for different cultural
operations e.g. hoe.
For weeding, toria for sowing and panga for cleaning these tools
usually made of wood or iron or both of them.
Animal power used in agricultural practices through draft
implements e.g. ploughs, seeders, and carts. Animal draft implements can
be manufactured locally from scrap material, which makes it cheap and
available. In cases of using animal power is also used for control and
management (Fashina, 1986).
Tractor power is used under certain conditions and always
unavailable for rural societies because of small size lock of technical
awareness and high cost of its use, more over, tractors are not available in
most cases in rural areas (Bansal, 1992). But tractor played large
contribution as source of power in modern areas. Tractor power is
delivered to onto implements in four ways the draw bar, the belt pulley,
the power take of, the power lift, or hydraulic control (Barger, 1961).
Hydraulic control
Hydraulic control described by Smith (1976) that is basically
method of transmitting power from the power source to machine or
component being operated.
Hydraulic control system, in addition to providing conveniently
located and easily operated control lever are extremely flexible in regard
to application possibilities cylinders may be built into the tractor, or
external cylinders may be mounted in various positions on the tractor on
trailed implement. This reported by Bainer (1955).
Hydrostatic, or the mechanics of fluids, was defined by Blasise
Pascal (1653). As follows:
Pressure applied to an enclosed fluid is transmitted equally and
undiminished in all directions to every part of fluid and of its restraining
surfaces.
Hydraulic systems for farm equipment
Farm equipment prior to the nineteenth – century era was animal –
drawn, guided by band, and lifted manually. Later, when equipment was
mounted on wheel, levers were used to raise and lower the working units
describe by Smith (1976). That:
The first mechanical power lift was developed for the trailing type
tractor-drawn plows about 1910. The tractor power lift was developed
about 1930 to raise and lower planters and cultivators mounted on the
row-crop tractor. The use of hydraulic power for lifting tractor-mounted
equipment was introduced in 1935. Hydraulic power lift are now used for
raising, lowering, and controlling almost all types of field equipment,
ranging from the small plow to the plat from of grain combine and the
drums of cotton- picking.
Hydraulic controls explain by Bainer (1955). That:
Mechanical power lifts on tractors were introduced commercially
in the late 1920’s following the advent of mounted cultivators and general
–purpose tractor. Hydraulic lifts of mounted implement appeared few
years later, and in the early 1940’s hydraulic controls for trailed
implements were adopted. Since that time, the development of hydraulic
control system has been raped. Electric and pnewmatric power lift have
been employed on only to eliminated extend.
Hydraulic mechanisms have been used reported by Hunt (1973)
that used in farm machinery since about (1935). The first production
hydraulic lift for tractor was introduced by deer &co. In (1939), Harry
Ferguson and henry Ford introduced tractor which used by hydraulics to
sense the draw bar pull of the implement and which transferred.
Fundamentals of hydraulic:
The fundamental law of hydraulic write by Smith (1976) that force
of (1Ib) acting on area of (1in2) can be used to lift weight of (10Ib) if the
area ander the weight is (10in2). In metric units, force of (454g) acting on
(6.45cm2) could by used to lift aweight of (4540g) if the weight had an
area of (64.5cm2).
Hydraulic symbols
Hydraulic symbols reported by Liljedaht (1979)that hydraulic
system have became so complicated that it is much easier toused symbols
to describe them. This language, Graphic symbols for fluid power
diagrams, must necessary be learned before proceeding to discussion of
hydraulic system.
The following list describes some of the advantages of using
symbols:
•
Their use simplifies publication of hydraulic circuits.
•
Complicated circuit can be tried out by using stock
hydraulic component “abroad board”.
•
•
Symbols save drawing time.
Symbols can be used to convey the functional requirements of
component, or an assembly of components, to design engineers with
out actually telling them how it must look.
Types of hydraulic systems
There are tow types of hydraulic system described by Jones(1966)
that is:
•
Closed –center, constant-pressure system because no oil is
pumped unless there demand for it from one of hydraulic
mechanisms, and when the operating valves control the hydraulic
mechanisms are in the neutral position, there is no flow of oil
through these valves. It is constant –pressure system for the reason
that with the engine and pump running constant pressure of
(2.300Ib.per sq) in maintained in the system.
•
The open-center system pumps oil constantly through the
hydraulic –mechanism operating valve and returns it to the
reservoir.
The advantages and disadvantages of close system
The following list described some of the advantages and dis
advantages of closed-center hydraulic system:
The advantages of closed –center are:
•
Simpler valving and circuits in the case of multiple uses.
•
Simpler feathering control and instant response with out
waiting for pressure build up.
•
Lower peak power requirement than in an open center
system.
The disadvantages of closed –center are:
•
All oil is pumped at high pressure although only small
proportion of the usage may require the pressure.
•
Valve must seal against the full pressure at all time to
avoid vesting energy.
•
Either variable-displacement pump or fixed displacement
pump with unload valve and accumulator required, compare with
only fixed in open. According to Lehann and Richey(1966).
Basic principles of hydraulics
The basic principles of hydraulics are few and simple explained by
Deere (1979). That liquid is no shape of their own because of this oil will
flow into passage of any size or shape. Liquid will compress slightly
under. Pressure also its transmit applied pressure in all direction and
liquids provide greater increases in work force. This principle helps you
to stop a large machine by pressing a bark pedal.
Basic oil circuits are described by Bainer(1955) that rated oil pressures in
early hydraulic system were some times as (300psi)pressure high
as(3000psi)are now used to limited extend, but the present trend is toward
rated pressure in order of (800 to 1200 psi).
The extensive use of hydraulic lifts and controls makes it essential –
that the operator modern farm equipment have an under standing of the
fundamental principles of power –lift hydraulic. According to Smith
(1976).
A system or design never malfunctions it operates exactly the way
you designed or built it. The struggle results from trying to make the
design, the operating conditions and your objectives compatible with one
anther reported by wittren.
Hydraulic system have become so complicated that it is much easier
to use symbols to described them this reported by Liljedah(1979).
Hydraulic used in farm equipment
First used of hydrostatic drivers in farm equipment reported by Hunt
(1973). That said no development were by the case company which
inserted at rogue converter into tractor ,s drive line and by inter national
harvester which first used hydrostatic drives in farm equipment .Since
initial applications, hydraulic have been used to aid in the control of
steering , braking, clutching, speed changing, and power transmission .
Special hydraulic system
Some late models of tractors, which have hydraulic powered brakes
and steering as well as implement control, are equipped with a hydraulic
system, which is specially designed to supply the power for these
different operations in the most efficient, and convenient manner,
described by Jones (1966).That is consists of main pump, power steering ,
power brakes, hydraulically operated rock shaft, one or two selective
control valves to operate remote hydraulic cylinders, transmission pump,
and an oil cooler. These components are connected together and supplied
with oil from a common reservoir-the transmission assures adequate
circulation of oil to the transmission part .The same oil which operates
the hydraulic mechanisms lubricates the transmission and differential
gears. It also changes and cools the main pump and routes the oil to the
cooler to maintain proper oil temperature, this system is known as aclosed
center.
Mounted equipment control systems
Loader, bulldozer, backhoes (excavator), and fork lift are usually
mounted on the machine which propels them. Often they are sold as
custom units for asingle job for easy of control, hydraulics is widely used
to operate this mounted equipment (Deere,1979) explain that in the
following :
•
Loader hydraulic system:
Most loader are mounted on the front of wheel or crawler tractor
which has it own hydraulic system, an open center type. Most loaders
have two kinds of control (raise and lower boom, dump and retract
bucket).
•
Bulldozer hydraulic system:
The bulldozer usually mounts on the front of crawler tractor for
greater traction in loose dirt. Most bulldozers have three types of
bulldozers(raise and lower, angle right and left ,and tilt side to side on
some bulldozers. All three are controlled by hydraulic .On other only one
or two.
•
Backhoe(excavator)hydraulic system:
The back hoe is used for digging trenches. It usually mounts on the
rear of an industrial tractor such as a loader or bulldozer. The operator
controls the backhoe by mean of levers. These levers direct oil through
control valve to the proper cylinder to operate the boom, bucket, crowd,
or stabling functions (with double acting cylinder, special swing cylinder
used to rotate the boom.
•
Fork lit hydraulic system :
The forklift is used to handle, and lift and stack products and
materials, many forklift are mounted on the rear of a wheel tractor. The
tract is then operated in reverse, the operator facing the forklift. Most fork
lift have three types of hydraulic control (lift and lower the fork, tilt the
mast fore, and to shift mast from side -to- side (optional).
Selecting hydraulic oil
Hydraulic oil for tractors are used for two purposes operating the
hydraulic implement control system, and operating the hydraulic steering
mechanism. Although there are four kinds of oil used the single- grade
and multi-grade crankcase oils of various types, Gear oil, hydraulic oil,
special oil, supplied by tractor manufacturers for use with their particular
tractor.
With any of the oil the designer of a machine takes into account the
effect the oil have on rubber seal or other rubber part in the hydraulic
system. Some tractor use oil from the transmission gear case, but even
tractors with an entirely independent hydraulic system are designed to use
a particular oil.
Hydraulic energy
Hydraulic energy is transmitted in two ways :
In he hydrodynamic system force is transmitted by high velocity
fluid flow hydrokinetic system, and the kinetic energy of the fluid does
work when it is decelerated by mechanism such as turbine wheel. A
hydraulic system that transmits energy primarily by pressure is called a
hydrostatic system, but all hydraulic system used in farm machinery is a
hydrostatic (Hunt,1973).
The average annual energy requirements for the proposed work of
tractor must be know before an optimum power level can be selected,
field operation energy can be estimated for any given farm from the
perforance of an existing implement (Hunt, 1979).
Chapter three
Material and methods
3.1
Site description:
This study was conducted to evaluate the performance of hydraulic
pump, in three schemes that is Khartoum State Ministry of Agric., Gezira
Scheme, and Kenana Company. Pumps used were mainly of 5.5 Gallon
per min delivery pumping from reservoir to other parts of hydraulic
system.
Khartoum State is located between longitude 32o – 33o East and
latitude 15˚ –16˚ North and latitude of 380m above mean sea level . The
total area of the state is about 28185.299 square kilometers .
The climate of the area is arid and semi arid with an average mean
annual rain fall of 160 mm (Shambat Agrometeo-logical station). The soil
of the areas can be broadly classified as clay – loams; with a relatively
high percentage of silt along the Blue Nile and main Nile banks.
Gezira scheme falls under a semi – arid tropics with humid rainy
season from July to October. The maximum monthly temperature is in the
range of 35˚ to 38˚C.
The soil of the project are deep cracking , self mulching clays , with
low infiltration rates, low permeability but high water holding capacity.
The over all mean average annual rain fall is around 200 mm.
(meteorological station of Wad Madani Research Station).
Kenana Sugar Company is located between the White Nile and Blue
Nile , 240 Km south of Khartoum , at latitude 13˚ North , longitude 33˚
East and is 500 m above sea level. The climate is tropical with a summer
rainy season four months, June to September, with a peak in August.
Annual rain fall is 316 mm and fluctuates greatly among years.
The soil is brown heavy clay, classified as true vertisols . The upper 60
cm of the soil profile is a cracking clay with 40 – 60 % clay content, the
dominant clay mineral is montmorillonite .The soil PH ranges from 7.5 –
8.5.
The studied areas were density populated with hydraulic pumps
scheme or company. The schemes farm vary in area from 30 – 450 m2 in
field crops but common area from 90 – 200 m2 in total area of 2.2 million
feddan in company farm they are vary in furrows from short furrows to
long furrows are from 45 m – 2500 m in total area of 35714 hectares in
area company .
3.2
Data collection:
Data collected were either in form of a questionnaire or parameters
calculation.
3.2.1 Data from questionnaire:
Data calculated an either general or specific data about machine
performance, hydraulic pump, hydraulic system (Appendix A).
3.2.2 Parameters calculations:
These Calculations were done using the following equations:
a- Hydraulic horse power (H.P) :
The (H.P) was determined using the formula stated by Hunt
(1973) & Sons (1984), as follows:
H.P = PQ
1714
Where:
P : Pressure (Psi)
Q : flow rate or pumps rated as delivering Certain flow
(gall/min)
b- Brake horse power (BHP).
When the driving unit is an engine the (BHP) was calculated
by dividing the fuel consumed in litres per hour by 0.23 (Michael,
1978). 0.23 litre of fuel is equivalent to one brake horse power.
this can be expressed by the following equation :
BHP = fuel Consumption In L / h
0.23
c- Actual pump efficiency:
The actual pump efficiency was calculated using the formula
stated by Israelsen and Hansen (1962); and Michael (1978) & Sons
(1984), as follows:
EP = HP
BHP
Where:
EP
= pump efficiency (percent)
HP
= hydraulic horse power
BHP = brake horse power
Appendix B, shows the sample calculation of pump efficiency,
while Appendix C1-C3 show the actual pump efficiency for the
pump schemes covered in the study
Power Consumption
3.3
In pumps studied, operated with fuel to do work with
hydraulic oil. The letter “F” was used to denote fuel (diesel)
consumption and “O” was used to denote hydraulic oil
Consumption.
Three levels of operation were assumed:
“1” F1 or O1 amount of fuel or oil consumed respectively, to
apply hydraulic machines at the existing Practice and efficiency
“2” F2 or O2 amount of fuel or oil consumed respectively when the
pump is operated at the existing efficiency (low efficiency) to apply
only the required hydraulic work.
“3” F3 or O3 amount of fuel or oil consumed respectively when the
pump is operated at it is optimum condition i.e. at it’s maximum
assumed efficiency of 60 percent to apply only the required
hydraulic work .
Then for the sake of comparison :
“i” F1 or O1 were compared with F2 or O2 using the T – test
for paired samples .
“ii” F2 or O2 were compared with F3 or O3 using the T – test
for paired samples .
“iii” F3 or O3 were compared with F1 or O1 using the T – test
for paired samples .
Pumps types
Vane
Gear
Piston
Fig. 2.1 –Types of hydraulic pumps on basis of oil
circuits
Source : Bainer (1955)
Pumps types
Piston
Gear
Vane
Internal
Balanced
Unbalanced
Axial
Inline
External
Radial
Rotating
Bent axis
Rotating piston
Fig. 2.2- Types of hydraulic pumps on basis of oil
and design
Source : Deere (1979)
Radial piston
used on motor
low pressure
Pumps
types
A spur - gear
used on tractor
hydraulic system
Low pressure
Spur - gear
Internal
Used in grerotor
Vane
Used on tractor
hydraulic system
Higher pressure
Fig. 2.4- Types of hydraulic pumps on basis of used
and oil pressure
Source : Barger (1951) .
Radial piston
used on motor
low pressure
Pumps
types
A spur - gear
used on tractor
hydraulic system
Low pressure
Apur - gear
Internal
Used in greotor
Vane
Used on tractor
hydraulic system
But
Fig.2.3- Types of hydraulic pumps on basis of use
and oil pressure
Source : liljedahi (1979)
References:
Abdalla y.A (2000) Development and evaluation of aridger – planter
Implement, M.Sc. Thesis dept . of agriculture university of Khartoum .
SAE. (1964). Selecting and staring tractor fuels and lubricants. Annual
report of American Association for Agricultural Engineering and
vocational fuels and Agriculture and Agriculture.
Bainer , R , kepner , R.A , and Barger , E.L. (1955). Principles of farm
machinery . California university, Inc. USA.
Bainer, R , kepner , R.A. and Barger . F.L . (1980) .Principles of form
machinery . and printing . AVI Publishing company, Connecticut , Inc
.USA .
Barger. E.L.et.al .(1951) . Tractor and their power Units massFerguson . Second edition . Inc . New Delhi lowastate .
Barger . E. L . et . al (1961) Tractor and their power Units . Third
edition. Inc .USA .
Bansal , R . K . (1992) . performance of draft animal to work in
morocoo. Draft ability and power out put AMA, Inc. Japan.
ILO . (1989) . Training manger for appropriate technology choice .
Annual report . International lab our Organization . Geneva , Swwises .
Israelsen , W . O and Hansen , E . V . (1962) . irrigation principles and
practices . third edition . John Wiley and Sons , Inc New York .
James , G . L . (1988) . Principles of farm Irrigation system design .
John Wiley and Sons , Inc . New York , USA .
John Deere & company . Moline (1979) . Hydroulic system . Third
edition Print in USA .
Johes M . S and Fred , R . (1966) Farm gas engines and tractor , M . C
G row – Hill Book company , Inc . New York .
John Deere , Combine Harvester (FMO) , (1987) . Fundamentals of
machine operation .
Fashina (1986) . Animal draught . A source of power for agricultural
deve lopment in a developing country . AMA . Inc . Japan .
Liljedahi . J . B . (1979) . et . al . Tractor and their power units . Purduc
university , Inc , USA .
Richey . C . B and Lehmann , H . A . (1966) A tractor closed – center
Hydraulic system . report , tractor and Implement Division , Ford
company. Inc. New York.
Kepner. R. A. et. al (1978). Principles of farm machinery. Avipublishing
company. Inc. Westport Jonnecticut .
Moline , E (1991) . Simulation Modeln to Predict operating Pressure and
Flow rates for Sprinkle system in operation . Unpublished M.Sc . Thesis
Dept. of agric. and Irrigation Eng. Utah state. univ. Logan. Utah.inc.
USA.
MOA . (1991) Critical sectoral lssves and future strategy for
development . Ministry of Agriculture MOA . Botswana’s agricultural
policy . Government Printer Gaborone , Botswana .
Michael .A . M (1978) . Irrigation . Theory and Practice VIK as
Publishing House PVTLTD New Delhi , India .
Schwab , G . O , Frevert . R . K ; Edminster . T . W . , Barnes . K . K .
(1966) . Soil and water Conservation Engineering . Second edition .
John Wiley and Sons , Inc . USA .
Smith , A . E . and Wilkes, M. S (1976). Farm machinery and equipment
, sixth edition . Mc Grow Hill , Inc . USA .
Sons, J.W. (1984). Design of Agricultual machinery, University of New
York, Inc. USA.
Hunt, D. et. al. (1973). Farm machinery University of Urbana, First
edition , Inc . USA .
Hunt , D . (1973) . Farm Power and machinery management , lowa state
University . First edition , Inc . USA .
Hunt , D (1979) . Farm Power and machinery management , Lowa state
university Pressames Lowa , Inc , USA.
Appendix B
The sample Calculation of pump efficiency
These Calculations were done with the help of data obtained
and equations relevant in literature in the following forms :
d- Hydraulic horse power (H.P) :
The (H.P) was determined using the formula stated by
Hunt (1973) & Sons (1984), as follows :
H.P = PQ
1714
Where :
P : Pressure (Psi)
Q : flow rate or pumps rated as delivering Certain
flow (gall/min)
e- Brake horse power (BHP).
When the driving unit is an engine the (BHP) was calculated by
dividing the fuel consumed in litres per hour by 0.23 (Michael, 1978).
I.e.o.23 litre of fuel is equivalent to one brake horse power hour .
this can be expressed by the following equation :
BHP = fuel Consumption In L / h
0.23
Actual pump efficiency :
The actual pump efficiency was calculated using the formula
stated by Israelson and Hansen (1962) ; and Michael (1978) & Sons
(1984), using the hydraulic horse Power (HP) and Brake horse Power
(BHP) as follows:
EP = HP
BHP
Where :
EP
= pump efficiency (percent)
HP
= hydraulic horse power
BHP = brake horse power
Appendix B, shows the sample calculation of pump efficiency,
while Appendix C1-C3 show the actual pump efficiency for
the pump schemes covered in the study
Chapter Four
Results and Discussions
4.1 Actual Pump Efficiency:
Table 4-1 shows the main information about the twenty four pumps studied on
the Khartoum State Ministry of Agriculture, Gezira Scheme, Kenana Sugar Company;
while Appendix B shows the calculated pump efficiency. It can be seen that the
hydraulic pumps in Gezira Scheme is of relatively low efficiency compared to that in
Khartoum State Ministry of Agriculture and Kenana Sugar Company. This could be
due to the effect of old pumps used.
The efficiencies shown in (Table 4.1) were statistically analyzed and presented
in a form of minimum, maximum, mean pump efficiency and standard deviation
(Table 4.2). The standard deviation in pumping efficiency was greater in Gezira
Scheme pumps than between those from Kenana Company and Khartoum State
Ministry of Agriculture while that from the whole sample of 24 pump is greater than
18 percent.
Table 4.3 (a-d) shows respective T-value test for comparison between
obtained actual pump efficiencies and assumed pump efficiency of 60 percent for
Gezira, Khartoum State, Kenana and total pumps considered. This test shows a
significant effect in efficiencies due to pump locations.
The low pump efficiency values shown in tables 4.1 and 4.2 indicate that these
pumps were operating at conditions far below that recommended. According to Deere
(1979), the maximum standard hydraulic pump efficiency of three pump types were
Gear 75 percent, vane 85 percent, piston 95 percent under very favourable conditions.
In the study most of pumps were very old and most of them were more than 20
years old. Results obtained in Appendixes C1, C2 and C3 showed that, there were
very few pumps with efficiency more than 75 percent, few pumps with efficiency
more than 60 percent and the bulk of pumps having efficiency under 60 percent.
Therefore, the efficiency of 60 percent was assumed to be as standard maximum
pump efficiencies.
Table 4.1: The Main Information and Types of Hydraulic Pumps of Khartoum State, Gezira Scheme
and Kenan Sugar Company (mean)
Gear
Gear
Vane
Vane
Piston
Piston
Del.
Press.
deliv.
Press.
Deliv.
deliv.
(Gpm)
(Psi)
(Gpm)
(Psi)
(Gpm)
(Psi)
Fuel
Oil
Machine
Location
Pump
Company consum
consum
H.P
B.H.P
type
Khartoum State
16.00
1600
-
-
Gezira Scheme
7.86
1825
8.33
Kenana Sugar Company 5.90
1920
6.40
7.00
efficen. (%)
(g/h)
(g/h)
4000
4
5
4.83
0.0350
14.80
20.93
71.98
1833.33 11.33
2400
5
4
5.05
0.0276
10.72
18.61
49.71
2000.00 6.50
3800
6
2
2.77
0.0265
9.13
12.04
74.52
Table 4.2: Minimum, Maximum, Mean and Standard
Deviation of Pump Efficiency from Khartoum State
Ministry of Agriculture, Gezira Scheme and Kenana Sugar
Company
Location
Khartoum State
Gezira Scheme
Kenana Sugar
Company
N
4
10
10
Min.
60.30
27.60
63.10
Max.
89.50
75.30
89.50
Mean
71.98
49.71
74.52
St. dev.
11.86
18.05
9.32
Total
24
27.60
89.50
58.55
13.076
Table 4.3: T-value for the Difference Between Mean Pump
Efficiencies and Assumed (60%) Efficiency
(a)
Khartoum State Ministry of Agriculture and
Correspond-ing Efficiency
Variables
Mean pump efficiency
N
Mean
4
71.98
Difference
t-value
2.3701 (cal)
10.3842
Standard efficiency
4
60%
*
2.2280 (tab)
In this table and the following tables:
Cal = calculated t-test; Tab = tabulated t-test
* Significant effect.
Prob. (P≤0.05)
(b) Gezira Scheme and Corresponding Efficiency
Variables
N
Mean
Mean pump efficiencies
10
49.71
Difference t-value
Prob. (P≤0.05)
3.7605 (cal)
6.4620
Standard efficiency
*
10
*
2.1765 (tab)
60%
Significant effect.
(c) Kenana Sugar Company and Corresponding Efficiency
Variables
Mean pump efficiencies
Standard efficiency
N
Mean
Difference
t-value
4
4
74.52
60%
6.6693
4.3998 (cal)
2.1320 (tab)
Prob.
(P≤0.05)
*
* Significant effect.
(d) Total pumps and Corresponding Efficiency
Variables
N
Mean
Difference
t-value
Mean pump efficiencies
Standard efficiency
* = Significant effect
24
24
65.312
60%
7.0362
2.3581 (cal)
2.2009 (tab)
Prob.
(P≤0.05)
*
4.2 Factors Affecting Pump Efficiency:
From table 4-1, 4-2 and 4-3 it appears that most of pumps were operating at
low efficiency compared with standard efficiency.
The reason for such low efficiencies implied further consideration of the
influential factors such as: pump condition, machine ownership, effect of spare parts
and specified tool of Diagnosis, operator skill and training and land ownership.
4.2.1 Condition of Hydraulic Pump:
The effect of the condition of hydraulic pump on it’s efficiency could be
considered with respect to pump delivery, age of pump maintenance frequency,
working hours and type of power, as follows:
a- Pump Types Delivery:
The pumps considered were limited to those between 5.5 to 23 gallon per
minute on three pumps types studied (gear, vane, piston pumps delivery).
From the studied about 45% were gear delivered, 20% vane delivered, 33%
piston delivery, table (4.4). Statistical Analysis (chi-square) at probability level of
significance of P ≤ 0.05 shows a significant effect of pumps types delivery on pump
efficiency.
Table 4-4 shows their statistical analysis revealed that the pumps types
delivery has significant efficiency of work.
Pump type delivery has significant effect on the efficiency of
pumping (Table 4.4). This was obviously attributed to the fact that most
of schemes the delivery to be 5.5 gallon per minute this less for
recommended of manual of manufacturer. The recommended the fluid
level in reservoir too low, pump speed too slow, sludge or dirt in the
pump (instruction manual of Deere Manufacturer No. ISBN. O-86691018-2).
Table 4.4: The Effect of Pumps Types Delivery on Pump
Efficiency (chi-square test)
Pumps types
delivery
Gear delivery (Gpm)
Vane delivery (Gpm)
Piston delivery (Gpm)
Percentage (%)
Chi-sq. value
Prob. (P≤0.05)
45.83
20.83
33.34
12.035
*
* Significant effect.
b- Age of Hydraulic Pump:
Appendix E1-E3 shows the age of hydraulic pumps (power unit and pump)
studied. The correlation coefficient relating age of hydraulic pump with the
corresponding efficiency was about 0.3765 (Fig 4.1), which is not significant at
P ≤ 0.05 level. This indicates that pump age (power unit and pump) has no effect on
efficiency of pumping.
The value of correlation coefficient (r=0.3765) between pump age and it’s
efficiency Indicated that, as the pump age increases the pump efficiency tend to be
decrease (Fig 4.1). a similar statement was reported by Israelsen Hansen (1962).
However, if these pumps were properly maintained, the age effect would have been
smoothed and thus the working life of pump increased.
c- Maintenance Frequency:
The maintenance frequency in the study was considered as yearly, seasonal
(i.e. winter and summer seasons) or irregular (i.e. when there is a breakdown). From
the 24 pumps studied about 29% were maintained yearly, 54% seasonally and 17%
were irregularly maintained (Table 4.5).
Statistical analysis (Chi-square) at probability level of significance of
P ≤ 0.05 shows a significant effect of the maintenance frequency on pumping
efficiency.
Observation and discussions with operator’s or engineer’s interviewed in this
study revealed the programme maintenance were yearly or seasonally and usually
maintenance was made when there was a break down. Moreover, there was no
qualified personnel or engineering to do the job and usually done by operator’s
themselves with the help of local mechanics. Investment in such kind of maintenance
services through mobile workshops or workshop in the locality could improve the
situation greatly. The importance of maintenance for pumps was emphasized by
Michael (1978), who stated that for safe and efficient operation of pump, lubrication
of different that part should be carried out strictly according to manufacture’s
instructions. He also added that maintenance frequency may range from one to six
months for hearing parts and it may reach a year for other part.
Table 4.5: The Effect of Maintenance Frequency on Pump
Efficiency (chi-square test)
Maintenance
frequency
Percentage (%)
Chi-sq. value
Prob. (P≤0.05)
16.67
54.17
29.16
11.9501
*
Irregular
Seasonal
Yearly
*
Significant effect.
d- Working Hours per Day:
Appendix E1-E3 shows the number of working hours for each pump and the
corresponding pump efficiency. It can be seen that for most of these pumps the
working hours were about 20 hours or less per day, in few cases there were about 6.6
working hours per day.
The correlation value 0.5549 (Fig 4.2) indicates that working hours per day
have significant effect on pump efficiency. However, continuous operation will
certainly affect pump efficiency as stated by Israelsen and Hansen (1962). This
significant effect could be attributed to the fact that these pumps were operated high
frequent (average range between 16-20 hours per day) and probably high than
recommended.
e- Type of Power:
The power type (diesel or oil) operating each of these pumps is shown in
appendix C1-C3. All pumps studied were operated by diesel to pumping oil (Table
4.7).
The statistical analysis (chi-square) at P ≤ 0.05 level of significance shown in
table 4.6 revealed that the type of power used has no effect on the efficiency of
pumping.
This is because both diesel and fluid as power types were converted into BHP
and transmitted to pump in a farm of revaluations per minute RPM from the shaft of
the prime mover. The magnitude of BHP depends on the amount and not on the type
of power used, capacity of prime mover and it’s transmission efficiency. However,
the running cost of pump as prime mover could be more in a form of fluid
consumption and also the pump need more spare parts, frequent maintenance and
repair than that of fuel pump.
Table 4.6: The Effect of Type of Power on Pump Efficiency
(chi-square test)
Fuel
Percentage (%)
100
Oil
100
Type of power
Chi-sq. value
Prob. (P≤0.05)
0.9231
n.s
n.s: No significant effect.
4.2.2 Spare Parts of the Hydraulic Pump and Specified Tool
of Diagnosis:
The effect of the spare parts of the hydraulic pump on it’s efficiency could be
considered with respect to availability of spare parts, and quality of spare parts,
specified tool of Diagnosis, as follows:
a- Availability of Spare Parts:
Appendix E1-E3 shows the availability of spare parts for each pump and the
corresponding pump efficiency. About 70.8% of the pumps studied has available of
spare parts while 29.2% of these pump is no available of spare parts (Table 4.7).
The statistical analysis (chi-square) at P ≤ 0.05 level of significance shown in
(Table 4.7) revealed that the availability of spare parts has a significant effect of the
efficiency of pumping.
b- Quality of Spare Parts:
The quality of spare parts to each pumps is shown in appendix E1-E3. about
87.5% of the pump studied got good quality of spare parts while 12.5% of these pump
got low quality spare parts (Table 4.8).
The statistical analysis (chi-square) at P ≤ 0.05 level of significance shown in
table 4-8 revealed that quality of spare part for pumps has a highly significant effect
on the efficiency of pumping.
Table 4.7: The Effect of Availability of Spare Parts on Pump
Efficiency (chi-square test)
Availability of
spare parts
Available
Percentage (%)
Chi-sq. value
Prob. (P≤0.05)
70.83
9.7182
*
Not available
29.17
* Significant effect.
Table 4.8: The Effect of Quality of Spare Parts on Pump
Efficiency (chi-square test)
Quality of
spare parts
Percentage (%)
Fine
87.5
Low fine
12.5
Chi-sq. value
Prob. (P≤0.05)
13.0081
**
** Highly significant effect.
C- Specified Tool of Diagnosis:
Appendix E1-E2 shows the specified tool of diagnosis for each of these pumps.
About 37.5% of few specified tool of diagnosis were 20.8% for very few and 41.7%
for a lot of specified tool of diagnosis, (Table 4.9) shows the statistical analysis (chisquare) at P ≤ 0.05 level of significance. This analysis revealed that the pump
specified tool of diagnosis has a significant effect on the efficiency of works.
Table 4.9: The Effect of Specified Tool of Diagnosis on Pump
Efficiency (chi-square test)
Specified tool of
diagnosis
Very few
Few
high
*: Significant effect.
Percentage (%)
Chi-sq. value
Prob. (P≤0.05)
20.83
37.50
41.67
8.3694
*
Available of spare parts (Table 4.7), available of specified tool of diagnosis
(Table 4.9) has significant effect on pump efficiency, but quality of spare parts (Table
4.8) has high significant effect on pump efficiency. These high effect was attributed to
the fact that quantity of spare parts established by operator’s was below that
recommended by manufacturer, also effect on pump efficiency that good quality
increase pump efficiency but bad quality decrease pump efficiency.
4.2.3 Machine Ownership:
Appendix E1-E3 shows machine ownership in the three schemes. It can be seen
that for most of these pumps the machine ownership were owned or rented in few
cases.
Correlation value of 0.2792 (Fig 4.3) indicates that machine ownership have
no effect on pump efficiency. It was originally believed that scheme who rented or
owned machine might be more serious and eager to get maximum possible profit
either through decreasing pumping cost through more efficiency pumps or increasing
crop yield.
4.2.4 Operators Skills and Training:
Social factors such as hydraulic operator’s education, skill and experience of
hydraulic operator’s were shown in appendix D1-D3 as follows:
a- Hydraulic Operator’s Appointment:
Appendix D1-D3 shows that about 41.7% of the operators were seasonally
appointed & constant, 41.7% were constant & leas, while 16.7% are in constant jobs.
Statistical analysis (chi-square) at P ≤ 0.05 level of significance (Table 4.10) shows
that there is significant effect of hydraulic operator’s state of appointment on pump
efficiency.
b- Hydraulic Operator’s Education level:
Hydraulic operator’s education level were shows in appendix D1-D3. about
37.5% of were engineers, 20.8% were general operator’s, while 41.7% were
experienced. Statistical analysis (chi-square) at P ≤ 0.05 level of significance (Table
4.11) shows that there is a significant effect of hydraulic operator’s education level on
pump efficiency.
Table 4.10:The Effect of Hydraulic Operator’s Work on
Pump Efficiency (chi-square test)
Hydraulic
operators
Constant
Constant + leas
Constant + seasonal
Percentage (%)
Chi-sq. value
Prob. (P≤0.05)
16.66
41.67
41.67
12.8462
*
*: Significant effect.
Table 4.11:The Effect of Operator’s Education Level on
Pump Efficiency (chi-square test)
Operator’s
education level
Percentage (%)
Chi-sq. value
Prob. (P≤0.05)
37.50
20.83
41.67
10.1802
*
Engineering
General
Experience
*
Significant effect.
c- Hydraulic Operator’s Skill:
Appendix D1-D3 shows the hydraulic operator’s skill. The correlation
coefficient relating operator’s skill to hydraulic pump efficiency was about 0.58 (Fig
4.4) which is significant at P ≤ 0.05 level of significance. This indicates that pump
operator’s skill has a direct effect on efficiency of pumping.
Hydraulic operator’s work seasonally or constant shown in (Table 4.10),
hydraulic operator’s education level (Table 4.11), hydraulic operator’s skill has
correlation factor’s of 0.58 show in (Fig 4.4) all these factor’s were significant effect
on pump efficiency. These efficiency attributed to the fact that if the operator’s has
high skill, high education level, work constant or seasonally this will be application
all recommended of manual of manufacture these increase pump efficiency. This
stated by Deere (1979) that the majority of hydraulic pump failure are due to human
factor. Also stated for prevent from this failure by know your hydraulic, maintain the
system, operate it as designed.
4.2.5 Land Ownership:
Appendix D1-D3 shows the form of land ownership in the schemes covered.
About 58.3% of the schemes were privately owned while about 41.7% were
combined. Statistical analysis (chi-square) at P ≤ 0.05 level of significance (Table
4.12) showed that there is a highly significance effect of land relationship on pump
efficiency.
It was originally believed that scheme who companied the land might be more
serious and eager to get maximum possible profit and application the recommended of
manufacture either through decreasing hydraulic pump cost through more efficient
pump or increasing machine yield or crop yield than that owned.
Table 4.12: The Effect of Land Ownership on Pump
Efficiency (chi-square test)
Land
ownership
Percentage (%)
Owned
58.33
Companied
41.67
Chi-sq. value
Prob. (P≤0.05)
14.2367
**
**: Highly significant effect.
4.3 Power Consumption:
In this section
power consumed (fuel or hydraulic oil) is analyzed with
respect to pumping requirement to do work relative to that pressured. This analysis
was done at three level of performance as follows:
1- F1 or O1 fuel or hydraulic oil consumed when the pump is operated at the
existing machine conditions (i.e. actual delivery at the corresponding
efficiency).
2- F2 or O2 fuel or hydraulic oil required when the pump is operated at it’s
existing efficiency (low efficiency) to pump the required hydraulic oil to do
work.
3- F3 or O3 fuel or hydraulic oil assumed to be consumed when the pump is
operated at an assumed efficiency of 60 percent to give the required hydraulic
oil to do work.
4.3.1 Fuel Consumption (F):
All of the twenty four pumps studied were diesel operated. (Table 4.13) shows
the average number of working hours per day and the corresponding fuel consumption
at the three levels of operation F1, F2 and F3.
Table 4.13: Average number of working hours and the
corresponding fuel consumption (F1) existing (practice and
efficiency), F2 low efficiency and (F3) optimum efficiency in
gallon/day
1
Average working
hours/day
6.6
F1
(l/day)
26.40
F2
(l/day)
57.55
F3
(l/day)
26.66
2
6.6
21.78
70.57
32.45
3
6.6
39.60
109.30
50.29
4
6.6
39.60
138.66
40.79
5
12
48.00
27.60
22.08
6
12
72.00
27.84
41.76
7
12
48.00
24.29
22.08
8
6.6
52.80
25.34
33.79
9
6.6
39.60
117.00
23.76
10
20
90.00
174.60
80.10
11
20
90.00
98.04
102.60
12
20
86.00
88.20
108.36
13
20
70.00
122.40
71.40
14
20
120.00
55.80
148.80
15
15
45.00
103.05
48.25
16
15
45.00
140.40
64.80
17
20
50.00
116.50
53.50
18
20
50.00
136.00
62.50
19
20
66.00
213.84
98.34
20
20
46.00
106.72
49.22
21
20
108.00
320.76
147.96
22
20
34.00
96.56
44.54
23
16
32.00
75.84
34.88
24
16
32.00
89.28
40.96
Serial No.
The statistical analysis between F1 and F2 (Table 4.14), between F2 and F3
(Table 4.15) and between F1 and F3 (Table 4.16) gave a high significant difference
between them.
From (Table 4.13) the decrease in fuel consumption to apply the required
amount of hydraulic oil is evident although the existing pump efficiency is low. The
saving in fuel consumption could be great if pumping efficiency is improved and only
the amount of hydraulic oil required is operated to do work.
Table 4.14:
Variables
F1
F2
t-value for the difference between F1 and F2
N
Mean
Difference
t-value
24
24
56.324
105.67
49.346
3.4271 (cal)
2.0147 (tab)
Prob.
(P≤0.05)
**
** Highly significant effect.
Table 4.15:
Variables
F1
F3
t-value for the difference between F1 and F3
N
Mean
Difference
t-value
24
24
56.324
60.37
4.046
2.1616 (cal)
2.0147 (tab)
Prob.
(P≤0.05)
*
* = Significant effect.
Table 4.16:
Variables
F2
F3
t-value for the difference between F2 and F3
N
Mean
Difference
t-value
24
24
105.67
60.37
45.3
3.039 (cal)
2.0147 (tab)
Prob.
(P≤0.05)
**
** Highly significant effect.
Key:
Cal: Calculated t-test.
Tab: Tabulated t-test.
The power consumed diesel or fluid was greater than necessary to pump the
required amount. The difference between the amount of fuel needed to hydraulic
pump at existing pump efficiency (F1) and that needed to pump the required fluid at
existing efficiency (F2), was high significant effect (Table 4.14) and the mean
difference was about 49.346 gallon per day for each pump. As far as operator’s were
concerned fuel loss due to the excess fluid applied was more than 50 percent of that
needed leading to an increased cost of production.
The amount of fuel (diesel) used to pump fluid required at the pump efficiency
(F2) were significantly those needed if the pump operated at it’s maximum assumed
efficiency of 60 percent and only fluid requirement (F3). The difference between F2
and F3 in fuel losses might have resulted from low pump efficiency.
Fuel consumed for applying fluid required at assumed 60 percent efficiency is
50 percent less than that when the operator operated their pumps at their existing
pump efficiency and applying only the fluid requirement.
The amount of fuel used to pump more fluid than required at the pump
efficiency (F1), were significantly higher than those needed when the pumps could
have been operated at their maximum (assumed) efficiency and pump only the
required amount of fluid (F3) as shown in (Table 4.16).
Similar trends were obtained with fluid or hydraulic oil pump operated to do
work.
4.3.2 Oil Consumption (O):
All of the twenty four pumps studied were pumping hydraulic oil to do work.
(Table 4.17) shows the average number of working hours per day and the
corresponding hydraulic oil consumption at the three level of operation O1, O2, O3.
Table 4.17:Average number of working hours and the
corresponding oil consumption (O1) existing (practice and
efficiency), O2 low efficiency and (O3) optimum efficiency in
gallon/day
1
Average working
hours/day
6.6
O1
(l/day)
0.2376
O2
(l/day)
0.52
O3
(l/day)
0.24
2
6.6
0.3300
0.07
0.49
3
6.6
0.2376
0.66
0.30
4
6.6
0.1188
0.27
0.12
5
12
0.2280
0.23
0.10
Serial No.
6
Average working
hours/day
12
O1
(l/day)
0.0840
O2
(l/day)
0.10
O3
(l/day)
0.05
7
12
0.0240
0.02
0.01
8
6.6
0.6864
0.96
0.44
9
6.6
0.2376
0.31
0.14
10
20
0.2200
043
0.20
11
20
0.2200
0.55
0.25
12
20
0.4200
1.15
0.53
13
20
0.2800
0.62
0.29
14
20
0.4800
1.29
0.60
15
15
0.5550
1.28
0.60
16
15
0.5550
1.75
0.80
17
20
0.4400
1.03
0.47
18
20
0.4400
1.20
0.55
19
20
0.5600
1.81
0.83
20
20
0.3400
0.79
0.36
21
20
0.3400
1.01
0.47
22
20
0.2200
0.62
0.29
23
16
0.5920
1.4
0.64
24
16
0.5920
1.65
0.76
Serial No.
The statistical analysis between O1 and O2 (Table 4.18), between O2 and O3
(Table 4.19) and between O1 and O3 (Table 4.20) gave a high significant difference.
From (Table 4.18) the decrease in hydraulic oil consumption to apply the
required amount of fuel consumption is evident although the existing pump efficiency
is low. The saving in hydraulic oil consumption could be great if pumping efficiency
is improved and only the amount of fuel required is operated to do work.
Table 4.18:
t-value for the difference between O1 and
O2
Variables
N
Mean
Difference
t-value
Prob.
(P≤0.05)
24
24
O1
O2
0.35158
0.8600
0.508
4.6 (cal)
2.0147 (tab)
**
** Highly significant effect.
Table 4.19:
t-value for the difference between O1 and
O3
Variables
O1
O3
N
Mean
Difference
t-value
24
24
0.35158
0.400
0.0484
4.16 (cal)
2.0147 (tab)
Prob.
(P≤0.05)
**
** Highly Significant effect.
Table 4.20:
t-value for the difference between O2 and
O3
Variables
O2
O3
N
Mean
Difference
t-value
Prob.
(P≤0.05)
24
24
0.8600
0.400
0.46
3.833 (cal)
2.0147er
(tab)
**
** Highly significant effect.
Key:
Cal: Calculated t-test.
Tab: Tabulated t-test.
Chapter Five
Conclusions and Recommendations
5.1 Conclusions:
The results obtained from the study lead to the conclusions presented in the
following sections:
5.1.1 Pumps were operated in Kenana company at a high
efficiency and low efficiency in Khartoum State, but
in Gezira Scheme operated at a very low efficiency
which may be due to the following:
1- Most pumps selection procedure were not based on pump characteristics
curves. i.e. it should consider the pump delivery and the required pressure.
2- Improper maintenance especially for old pumps.
3- Power transmission from engine to pump was generally very poor. This is
probably because speed between engine and pump were not matching.
4- There was a loss of fuel due to leakage from fuel tanks or pipes of fueling
system commonly used.
5- Loss of fluid due to leakage from worn pump and connection pipes of
hydraulic system.
5.1.2
Agricultural administrations on Khartoum State and Gezira Scheme did not
extend their services beyond selling pumps. Staff did not include engineers
specialized in pumps and power units. On the other hand agricultural administration
authorities have no good experiences in hydraulic pump.
5.1.3
All Machine in Kenana Company were owned by the company which most
machines in Gezira were rented but all machine in Khartoum State were rented, so,
low availability of spare parts and very few diagnosis devices, were observed.
5.1.4
Hydraulic operator’s were very low skill, low education level, and low
experience in hydraulic systems.
5.1.5
Agricultural extension services in hydraulic machines were very limited and
sometimes completely absent.
5.2 Recommendations:
From the results and conclusions of this study the following recommendation
can be made:
1- Grouping of the Gezira scheme holdings into larger ones is a necessary for
economizing on running cost and better control and management.
2- Establishment of an agricultural administration concerned with hydraulic
pump for companies and schemes. This administration should be able to
perform the following activities:
(i) Pump selection procedure (type, delivery, make and model) relative to
operating conditions and area to be operated. Administration should
also be able to advice on better use of hydraulic work.
(ii) Following up installation, maintenance and repair.
(iii) Control of importation of pump and power units according to
technical specifications derived from field conditions.
(iv) Availability of spare part in good quantities.
3- Establishment of mobile workshops for maintenance, repair and periodic
investigation of hydraulic pumps.
Suggestions for further research can be summarized into:
1- The study should be extended to other areas of the Sudan using hydraulic
pumps.
2- Production on these schemes is expected to be very expensive compared to
that from company. Therefore, a study on economy of production and
probably through alternative cropping mixes and economy of using these types
of pumps (costs).
References
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– planter Implement, M.Sc. Thesis dept . of Agriculture
university of Khartoum .
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of farm machinery. California University, Inc. USA.
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of form machinery . and printing . AVI Publishing company,
Connecticut , Inc .USA .
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morocoo. Draft ability and power out put. Inc. Japan.
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edition. Inc .USA .
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edition, Inc. USA.
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lowa state University . First edition, Inc. USA.
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choice. Annual report. International lab our Organization .
Geneva , Swwises .
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principles and practices. Third edition. John Wiley and Sons ,
Inc New York .
- James, G. L. (1988). Principles of farm Irrigation system
design. John Wiley and Sons, Inc. New York, USA.
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Third edition Print in USA.
- John Deere, Combine Harvester (FMO). (1987). Fundamentals
of machine operation. Inc. USA.
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tractor, M. C G row – Hill Book company, Inc. New York.
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Avipublishing company. Inc. Westport Jonnecticut .
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University, Inc, USA.
- Michael, A. M. (1978). Irrigation. Theory and Practice VIK as
Publishing House PVTLTD New Delhi , India .
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development. Ministry of Agriculture. Botswana’s agricultural
policy. Government Printer Gaborone, Botswana.
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Pressure and Flow rates for Sprinkle system in operation.
Unpublished M.Sc. Thesis Dept. of agric. and Irrigation Eng.
Utah state. univ. Logan. Utah.inc. USA.
- Richey, C. B., and Lehmann, H. A. (1966). A tractor closed –
center Hydraulic system. report, tractor and Implement
Division, Ford company. Inc. New York.
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Annual report of American Association for Agricultural
Engineering and vocational fuels and Agriculture and
Agriculture.
- Schwab, G . O., Frevert. R. K; Edminster. T. W., Barnes. K.
K. (1966). Soil and water Conservation Engineering. Second
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University of New York, Inc. USA.
Appendix A1
Questionnaire of: performance and problems of the hydraulic pumps in heavy
agricultural machines.
A- General information:
1- Province: ……………………………………………………………….
2- Location: ……………………………………………………………….
3- Name of company/Establishment: …………………………………….
4- Owner’s names: ……………………………………………………….
5- Education level:
a- Agriculture b- General education c- Illiterate
d- Other
6- Land ownership:
a- owned
b- acquired
c- other
7- Scheme area ……………………………. Fed
8- Soil type:
a- clay
b- silt
c- sand
d- loam
B- Machines Performance:
1- Number of machines operation: ……………………………………….
2- Types of machines operation:
a- loader
no…..
no…..
b- excavator
d- bulldozer
no……
no…..
c-
motergrader
e- other ……….
3- Name of national companies of it:
a- Cat
b- Halla
c- Daewoo
d- Komatsu
4- Proper one annual: use …………………………………………………
5- Engine power
a- Loader
1) ….hp
2) ….hp
3) ….hp
b- Excavator
1) ….hp
2) ….hp
3) ….hp
c- Motergrader
1) ….hp
2) ….hp
3) ….hp
d- Bulldozer
1) ….hp
2) ….hp
3) ….hp
e- Forklift
1) ….hp
2) ….hp
3) ….hp
f- Other
1) ….hp
2) ….hp
3) ….hp
6- Fuel consumption:
a- Loader
…………………g/h
b- Excavator
…………………g/h
e- other
c- Motergrader
…………………g/h
d- Bulldozer
…………………g/h
e- Other
…………………g/h
C- Hydraulic Pumps:
1- Pump type: a- Gear
b- Vane
c- Piston
2- Delivery (Gpm):
a- Gear1/0.2-150
2/other
b- Vane
1/0.5-250
2/other
c- Piston
1/0.5-250
2/other
3- Pressure (Psi):
a- Gear1/250-2500
2/other
b- Vane
1/250-2500
2/other
c- Piston
1/750-2500
2/other
4- Speed (RPM):
a- Gear1/800-3500
2/other
b- Vane
1/1200-4000
2/other
c- Piston
1/600-6000
2/other
5- Maintenance frequency:
a- Seasonally
b- Yearly
c- Irregular
b- Yearly
c- Irrigular
6- Repair frequency:
a- Seasonally
7- Daily working hours
a- Summer
………………………………..hours
b- Winter
………………………………..hours
c- All years
………………………………..hours
d- Other
………………………………..hours
D- Hydraulic System:
1- Oil consumption gal/year:
a- Loader
1) ……..g/y
2) ……..g/y
b- Excavator
1) ……..g/y
2) ……..g/y
c- Motergrador
1) ……..g/y
2) ……..g/y
d- Bulldozer
1) ……..g/y
2) ……..g/y
e- Other
1) ……..g/y
2) ……..g/y
2- Hydraulic operation:
a- Constant
b- Constum labour
c- Leas labour d- Other
3- Hydraulic operator level:
a- Skill labour
b- Former
c- Other
4- Hydraulic maintenance and repair:
a- Experienced
b- skilled
c- Other
5- Distance of operated area from maintenance and repair workshop:
a- Adjacent
b- …. Meter (m)
c- … Kilometer (km)
6- Purchase price of machine:
a- High
b- Low
c- Other
7- Purchase price machine compare to spare parts:
a- High
b- Low
c- Other
8- Spare parts:
a- Loader
a- Availability
b- No availability
b- Excavator
a- Availability
b- No availability
c- Motergrader
a- Availability
b- No availability
d- Bulldozer
a- Availability
b- No availability
e- Other
a- Availability
b- No availability
9- Quantity of sparepart:
a- Cat:
1)fine
2) low fine
b- Halla:
1)fine
2) low fine
c- Daewoo:
1)fine
2) low fine
d- Banati:
1)fine
2) low fine
e- Komatsu:
1)fine
2) low fine
f- Other:
1)fine
2) low fine
10- Other problem of hydraulicsty systems:
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
………………………………………………………………………….
11- Future solution suggested:
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
………………………………………………………………………….
Appendix D1
Social Factors and Pump Efficiency in Sample of
Khartoum State Ministry of Agriculture
Pump
Hydraulic
Operator’s
Operator’s Land
operator’s
education
skill
1
Constant
Engineering Low skill
Owned
60.3
2
Khartoum Constant
Engineering Low skill
Owned
89.5
3
State
Constant
Engineering Low skill
Owned
76.2
Constant
Engineering Low skill
Owned
61.9
No. Location
4
relationship
efficiency
(%)
Appendix D2
Social Factors and Pump Efficiency in Sample of (4)
Workshop on the Gezira Scheme
No. Location
Hydraulic
Operator’s
Operator’s
Land
Pump
operator’s
education
skill
relationship
efficiency
(%)
1
Barakat
Constant
General
& leas
Constant
2
Very low
Owned
27.6
Owned
35.0
Owned
27.6
Owned
38.5
skill
General
Maringan
Very low
skill
Constant
General
Very low
skill
Constant
3
General
Hassahisa
4
Very low
skill
Constant
General
Low skill
Owned
35.8
Constant
Engineering
Low skill
Owned
53.6
Constant
Engineering
Low skill
Owned
68.4
El
Constant
Engineering
Low skill
Owned
75.3
Rawyan
Constant
Engineering
Low skill
Owned
61.2
Constant
Engineering
Low skill
Owned
74.1
Appendix D3
Social Factors and Pump Efficiency in Sample of (3)
Workshop on the Kenana Sugar Company
No.
1
Location
Hydraulic
operator’s
Operator’s
education
Operator’s
skill
Land
relationship
Constant
Experience
High skill
Compared
Pump
efficiency
(%)
63.1
Experience
High skill
Compared
86.1
Experience
High skill
Compared
64.1
Experience
High skill
Compared
75.2
Experience
High skill
Compared
89.5
Experience
High skill
Compared
64.0
Experience
High skill
Compared
82.1
Experience
High skill
Compared
78.4
Experience
High skill
Compared
65.5
Experience
High skill
Compared
77.0
(4)
& seasonal
workshop
Constant
& seasonal
Constant
& seasonal
Constant
& seasonal
Constant
& seasonal
Heavy
2
machine
workshop
Constant
& seasonal
Constant
& seasonal
Constant
& seasonal
Constant
& seasonal
Loader
3
workshop
Constant
& seasonal
Appendix E1
Pump Condition and Pump Efficiency in Sample of Khartoum State Ministry of
Agriculture
No.
Location
1
2
Khartoum
Gear
pump
Vane
pump
Piton
pump
Gear
-
-
Pump
age
(year)
8
-
-
Piston
7
Irregular
No. of
working
hours/day
6.6
Irregular
6.6
Maintenance
frequency
Rented
Available Quality
of spare of spare
parts
parts
Available
Fine
Rented
Available
Machine
relationship
Low
Specified
tools of
diagnosis
Few
Pump
efficiency
60.3
Few
89.5
fine
State
3
-
-
Piston
8
Irregular
6.6
Rented
Available
Fine
Few
76.2
4
Gear
-
-
8
Irregular
6.6
Rented
Available
Low
Few
61.9
fine
Appendix E2
Pump Condition and Pump Efficiency in Sample of (4) Workshop on the Gezira Scheme
No.
Location
1
Barakat
2
Maringan
3
Hassahisa
4
Gear
pump
Vane
pump
Piton
pump
Gear
-
Vane
Vane
-
Piston
Pump
age
(year)
22
21
21
25
Gear
-
-
Gear
-
Gear
-
Seasonally
Seasonally
Seasonally
Yearly
No. of
working
hours/day
12
12
12
6.6
24
Yearly
6.6
Owned
-
6
Yearly
20
Rented
Vane
-
Piston
5
7
Yearly
Yearly
20
20
Rented
Rented
Available
of spare
parts
Available
Available
Available
Not
available
Not
available
Not
available
Available
Available
-
Piston
8
8
Yearly
Yearly
20
20
Rented
Rented
Available
Available
Maintenance
frequency
Machine
relationship
Owned
Owned
Owned
Owned
El Rawyan
Quality
of spare
parts
Fine
Fine
Fine
Fine
Specified
tools of
diagnosis
Very few
Very few
Very few
Very few
Fine
Very few
35.8
Fine
Few
53.6
Fine
Low
fine
Fine
Fine
Few
Few
68.4
75.3
Few
Few
61.2
74.1
Pump
efficiency
27.6
35.0
27.6
38.5
Appendix E3
Pump Condition and Pump Efficiency in Sample of (3) Workshop on the Kenana Sugar
Company
No.
1
2
3
Location
(4)
workshop
Heavy
machine
workshop
Loader
workshop
Gear
pump
Vane
pump
Piton
pump
Gear
-
-
Pump
age
(year)
2
-
-
Piston
Gear
Gear
Gear
Gear
Vane
-
-
Vane
Seasonally
No. of
working
hours/day
15
2
Seasonally
15
Owned
Piston
Piston
-
2
2
2
2
2
2
2
Seasonally
Seasonally
Seasonally
Seasonally
Seasonally
Seasonally
Seasonally
20
20
20
20
20
20
16
Owned
Owned
Owned
Owned
Owned
Owned
Owned
-
2
Seasonally
16
Owned
Maintenance
frequency
Machine
relationship
Owned
Available
of spare
parts
Not
available
Not
available
Available
Available
Available
Available
Available
Available
Not
available
Not
available
Quality
of spare
parts
Fine
Specified
tools of
diagnosis
A lot of
Fine
A lot of
86.1
Fine
Fine
Fine
Fine
Fine
Fine
Fine
A lot of
A lot of
A lot of
A lot of
A lot of
A lot of
A lot of
64.2
75.2
89.5
64.0
82.1
78.4
65.5
Fine
A lot of
77.0
Pump
efficiency
63.1
Appendix C1
Information and Types of Hydraulic Pumps in Sample of Khartoum State Ministry of
Agriculture
No.
Location
Gear
delivery
(Gpm)
9
Gear
pressure
(Psi)
2000
Vane
delivery
(Gpm)
-
Vane
pressure
(Psi)
-
Piston
delivery
(Gpm)
-
Piston
pressure
(Psi)
-
Machine
Company
Loader
Komatsu
Fuel
consumption
(g/h)
4
Oil
consumption
(g/h)
0.036
H.P
B.H.P
10.5
17.4
Pump
efficiency
(%)
60.3
1
& Banati
2
-
-
-
-
5.5
4000
Fxcavator
Doewoo
3.3
0.05
12.8
14.3
89.5
-
-
-
-
8.5
4000
Bulldozer
Cat
6.0
0.036
19.8
26.0
76.2
23
1200
-
-
-
-
Donfing
China
6.0
0.018
16.1
26.0
61.9
Khartoum
3
4
State
& ZY
Appendix C2
Information and Types of Hydraulic Pumps in Sample of (4) Workshop on the Gezira Scheme
No.
1
2
3
4
Gear
delivery
(Gpm)
-
Gear
pressure
(Psi)
-
Vane
delivery
(Gpm)
5.5
Vane
pressure
(Psi)
1500
Piston
delivery
(Gpm)
-
Piston
pressure
(Psi)
-
Maringan
5.5
1500
8.0
-
2000
-
-
-
Hassahisa
8
2000
-
-
11.5
-
2000
-
10
8
1800
2000
11.5
-
2000
-
7.5
-
3000
-
-
-
-
-
15
2200
Location
Barakat
El
Rawyan
Fuel
consumption
(g/h)
4
Oil
consumption
(g/h)
0.019
H.P
B.H.P
4.8
17.4
Pump
efficiency
(%)
27.6
6
4
0.007
0.002
9.3
4.8
6.0
4
35.0
27.6
Cat
Cat
8
6
0.104
0.063
13.4
9.3
34.8
26
38.5
35.8
Komatsu
Daewoo
Cat
4.5
4.5
4
3.5
0.011
0.011
0.021
0.014
10.5
13.4
13.1
9.3
19.6
19.6
17.4
15.2
53.6
68.4
75.3
61.2
Cat
6
0.024
19.3
26.1
74.1
Machine
Company
Harvester
Cat &
Class
Cat
Cat
Bulldozer
Motor
Grador
Bulldozer
Motor
grador
Loader
Excavator
Motor
grador
Bulldozer
Appendix C3
Information and Types of Hydraulic Pump in Sample of (3) Workshop on the Kenana
Sugar Company
No.
Location
1
(4) workshop
2
3
Heavy
machine
workshop
Loader
workshop
Gear
delivery
(Gpm)
7
6
5.5
Gear
pressure
(Psi)
2000
2000
2000
Vane
delivery
(Gpm)
7
-
Vane
pressure
(Psi)
2000
-
Piston
delivery
(Gpm)
5.5
5.5
-
Piston
pressure
(Psi)
3500
4000
-
5.5
5.5
-
1800
1800
-
5.8
200
8.5
-
3900
-
Toft
Fuel
consumptio
n (g/h)
3
Oil
consumption
(g/h)
0.37
Loader
Cat
2.5
0.022
Excavator
Motor
grador
Bulldozer
Fork Gift
Loader
Cat
Cat
3.3
2.3
0.028
0.017
Cat
Cat
Cat
5.4
1.7
2
0.017
0.011
0.037
Machine
Company
Harvester
H.P
B.H.P
8.2
11.2
7.0
8.2
12.8
6.4
13
19.3
5.8
5.7
6.7
10.9
14.3
10
23.5
7.4
8.7
Pum
efficie
(%)
63.
86.2
64.2
75.2
89.5
64.0
82.
78.4
65.5
77.0