North Carolina State University
Omcc of Cootinlling Eduation and Rofariod Development
Dirkion of Univerdty Ertcadon
MEMORAHDUH TO:
Short Course Participants
Tho Offico of Continuing Education C Profomsional Dovelopment
(OCECPD) welcomes you to this North Carolina State University short
course. We hope your e%periences here are pleasant and rewarding.
If you have noeds while you aro h u e that aren't baing met, please
let um know.
i would
liko to call your attontion to on. important a8pect of your
You will be awarded Continuing
participation in thi8 cour80.
Education Unit. (CEDs) for muccessful completion of this program.
One CEU is awarded for u c h 10 hour8 of iMtruction, with the
undustanding that tho 8tudurtmut bo pro8ont for at least 908 of
the instruction. The CW is a nationally recognized uniform unit
of moamuramont providing the participant vith educational units
which can be accumulated and u e d a8 evidence of profemsional
development. In an incrusing number of irutances, CEWS are used
for certification, licuming and am a factor in promotion.
The staff greatly appreciate. your comment. about the program you
are attending. We also welcome suggestions for new courses to meet
your educational needs, as we are continually goarching for subject
areas not included in t h o more than 600 conferences, workshops,
short courses and seminars now being .offered.
Again, we are pleased to have the opportunity to s e n e you and hope
you return often.
B. Marston, Director
of Continuing Education
Professional Development
I
North Carolina State University
College of Textiles
The North Carolina State University College
of Textiles Serves the citizens of Nonh Carolina
through .education. research and extension programs.
Founded in 1899, this institution with an
enrollment of close to 1.OOO students, now dominates
textile education in the United States. At the present
time, nearly half of all textile university-based
undergraduate degrees are awarded here. Fifty
percent of all master’s candidates and 75 percent of
all textile Ph.D.’s are currently enrolled in the college.
Reflecting the diversity of the industry itself.
the curriculum includes Bachelor of Science degrees
in texules, textile and apparel managemenL textile
science, textile engineering and textile chemistry.
Within some of these degree programs, a student may
specialize in textile design. textile technology. textile
management, apparel management, polymer
chemistry. dyeing and finishing science, dyeing and
finishing technology, and dyeing and finishing
management
The textiles degree program is designed to
provide a broad foundarion in textile technology.
beginning with the basic raw material and progressing
through to the finished fabric. Students enrolled in
this curriculum may sptcialize further in the areas of
textile design or advanced textile technology. Textiles
program graduates typically fill design and
manufacturing management positions in fiber and
texule manufacturing fms.
-- -
Students enrolled in the textile and apparel
management program will obtain a solid background
in texules, in addition to management concepts and
applications. Specializationsin textile management or
apparel management arc possible. Graduates of hese
programs are in demand to fill positions in
production, tezhnical services, sales, markuing.
purchasing, personnel and other related management
and staff functions.
Another program offering outstanding
opportunities for students is the textile science
program. which emphasizes research, development,
and applications of advanced technology to the fiber
and textile industries. It is also a good choice for
students interested in pursuing advanced degrees in
scientific and technical disciplines.
Students studying textile chemistry can
concentrate on dyeing and fmishing science, polymer
‘science,dyeing and finishing operations. and dyeing
and finishing management. These students are in
great demand in the numerous textde operations that
emphasize dyeing and fmishing. many of which are
located in North Carolina. or in polymer-related
research and development activities throughout the
fiber and textile indusmes.
Students studying textile engineering leam
how to apply scientific principles and engineering
prar;tices to the widely diversified aspects of texule
processes. products and machinery. This degree
program is operawf jointly with the College of
Engineering.
The NCSU College of Textiles offers
muate programs leading to the Master of Science.
Master of Textiles. and Doctor of Philosophy degrees.
Graduates with advanced textile degrees are
constantly in short supply and great demand.
The curriculum of the college is v e d e and
comprehensive, providing instruction both on and off
campus. Extension programs provide numerous short
courses, conferences and workshops on a grtat variety
of subjects of interest to the fiber, textile and apparel
industries. In addition to these programs, Textiles
Extension also offers a wide variety of in-plant
courses.
Credit courses via the Textile Off-Campus
Televised Education (TOTE)Program are offered
internationally. Enrollment averages approximately
160 students pcr academic year. Courses are offered
at the undergraduate and graduate levels. Students
can eam a Master of Textiles with a specialization in
Textile and Apparel Management and Technology:
Textile Engineering and Science: and Textile
Chemistry. TOTE classes an available to any
individual seeking an improved textdes education or
background. In addition a visual aid rental seMce is
available u) the industry.
WEFT KNITTING FUNDAMENTALS
BUS SCHEDULE
AUGUST 22 - 25,1994
Monday, August 22
7:45am
4:OOpm
6:30pm
9:OOpm
Embassy Suites to College of Textiles
College of Textiles to Embassy Suites
Embassy Suites to Simpson’s
Simpson’s to Embassy Suites
Tuesday, August 23
8:OOam
4:OOpm
Embassy Suites to College of Textiles
College of Textiles to Embassy Suites
Wednesday,August 24
8:OOam
4:OOpm
Embassy Suites to College of Textiles
College of Textiles to Embassy Suites
Thursday, August 25
8:OOam
12:OO noon
Embassy Suites to College of Textiles
College of Textiles to Embassy Suites
WEFT KNITTING FUNDAMENTALS
Gary W. Smith
1.Knitting Yarns:
A. Yarn Classifications:
a. Spun:
Singles vs. Plied
Spun Yam Classifications And Comparisons
Ring
Open-End
Carded
Combed
strength
cost
uniformity
twist
cover
count range
b. Filament:
Flat vs. Textured
Influence of Filament Count and Stretch
1
c. Elastomeric:
Elastomeric Yam Comparisons
Bare
Single Covered Double Covered
cost
extensibility
stability
B. Implications of New Yam Developments:
a. package sizehhape
.
b. uniformity
c. friction
d. joining techniques
C. Yarn Requirements:
a. strength
b. count variation
c. uniformity
d. twist
e. friction
f. elongation
g. colorhhade
h. packaging
2
D. Yam Numbering Systems:
a. Indirect:
Cotton Count: number of 840 yard lengths per pound
Comparisons of Yam Counts
20/1
30/1
3012
cost
thickness
uniformity
b. Direct:
Denier: weight in grams of 9000 meters of y a m
Decitex: weight in grams of 10000 meters of yam
Comparisons of Yam Deniers
1/70/13 l/70/34
2/70/34
cost
thickness
Uniformity
Count Importances:
2. Weft Knitting:
A. Classifications:
a. Structure
aa. Jersey
bb. Rib
--
3
cc. Purl
Knitting
4
Weft Knitting Machine
_-
5
Weft Knitting
---
h
k ]&E%
Neech
4 I1
I11
6
b. Machine
aa. Single Cylinder
bb. Dial and Cylinder
3dd. Purl
cc. V-Bed
c. Format
aa. Tubular
bb. Flat
d. Diameter
aa. Small
bb. Large
B. Definitions:
a. Course: - a horizontal row of loops W
Feeder: - an actual course
Visual: - a visual course
CPI:
b. Wale: - a vertical column of loops
WPI:
Knit loop:
Tuck loop:
e. Float loop:
C.
7
Single Jersey
Technical Face
Technical Back
8
9
f. Feeder: - a unit which guides a yam to the needles
g. Needle: - an element which forms loops and wales
';1
h. Sinker: - an element on jersey machines which assists needles
hold fabric during knitting
i. Tricks: - slots which guide needles during knitting
j. Cylinder: - a cylinder drum which contains slots, needles and
(sometimes)sinkers
k. Dial: - a horizontal plate which contains slots and horizontal
needles
1. Loop Length: - the average amount of yam in a loop
m.Course length: - the amount of yam required t o knit one
complete course cnruuy
Run-In:
Ravel length:
Draw:
n. GuageKut: - normally the number of needles per inch
u
0.
IIIIIIIIIIII
Gaiting: - the arrangement of two sets of needles
Rib Gaiting: cr/
77
Interlock Gaiting:
77
--
p. Timing: - relative movement between two sets of needles or
~
needles and sinkers
q. Negative Feed: - yam pulled from the yam package by the
action of the needles
10
r. Positive Feed: - yarn metered to the needles at a preset rate
s. Yield: - the weight per unit of fabric
Oz/yd2:
Oflinear yard:
Yarddpound:
Conversions:
11
I
~
C. Knitted Fabric Properties:
a. Stretch and Recover:
~
i
b. Shrinkage:
c. Crease Resistance:
d. Spirality:
e. Snagging:
f. Pilling:
g. Bulk:
12
D. Notation:
a. Verbal:
b. Graphic:
c. Symbolic:
Knit
Face Rear
Tuck
Face Rear
B E I
E l m
Float
Face Rear
17
0
Examples:
d. Diagrammatic:
G
Knit (Rear)
2L
Tuck(Face) \d
Tuck(Rear)
A
Float (Face) Y
Floatwear)
A
RibGaiting
o
. - c
mit(Face)
Interlock Gaiting
0
m c
'
Examples:
13
,
E. Loop Classifications And Fabric Modifications:
Knit
KnitfI'uck
length
Knit/Float
width
thickness
cost
extensibility
effect
weight
knitability
CPI
F. Introduction to Machine Functions And Considerations:
a. Creel:
b. Knitting Zone:
c. Fabric Take-up And Collection:
14
3. Jersey Knitting:
A. Jersey Knitting Cycles:
a. Plain Jersey:
b. Tuck Jersey:
c. Float Jersey:
B. Camming Systems, Raceway Units And Notation:
15
Needle Cylinder
n
16
Ty picaI Cam System of Single Jersy Machine
*
Direction Of Needle Travel
I
NeedleMotionReuuired
I
Cleating
m
Running
Knockover
F
I
Loop Pulling
L
17
b
I
18
Latch Needle Activation
3
i
+
3
e
19
Movements of Latch Needles and Web Holding
Sinkers
A
a
D
20
A
Knit Loop
B
Tuck Loop
Tuck Loop Formation
21
A
Float Loop
22
Tuck Stitch Formation
Y
6
4
Y
P
A
@!
4
23
Y
Float Stitch Formation
Float Stitch Formation
24
C. Factors Influencing Knitability And Productivity:
a. yam characteristics:
b. yam specifications:
c. yam purchasing and storage:
d. machine character and tensions:
e. fabric structure and tightness:
f. ambient conditions:
g. cleanliness:
h. preventative maintenance:
i. inventory policies:
-- 1
j. operator/technicianload:
25
k. training:
1. detector usage and monitoring:
D. Single Knit Fabric Classifications:
Plain Jersey
Striped Jersey
Flat Jacquard
TerryNelour
Plaited Jersey
.E. Specific Jersey Fabric Characteristics:
a. Plain Jersey:
b. Striped Jersey:
c. Tuck Jersey:
26
Tuck Jersey
Fleece
Knit Loop
Float Loop
Tuck Loop
27
Laying-In
Weft Knit Fabric
28
d. Flat Jacquard
e. TerryNelour:
f. Fleece:
g. Plaited Jersey
F. Jersey Fabric Modifications:
29
G. Starfish Concepts:
a. Yam Control:
b. Course Length Control:
c. Tension Control:
30
I
4. Rib Knitting:
A. Rib Knitting Cycles:
a. Dial and Cylinder Machines:
b. V-Bed Machines:
B. Gaiting Considerations:
C. Needle Timing Considerations:
D. Rib Fabric Classifications:
a. Simple Ribs:
1x1
2x2
6x3
Half' Cardigan
2x1
Full Cardigan
b. Complex Ribs:
aa. Plain
Interlock
-- -
Ponte de Roma
bb. Relief
Cords
Blisters
cc. Flat Jacquard
2 Color
3 Color
31
3x3
Thermal
Cylinder and Dial
wTricks
d
32
Rib Gaiting
33
I
m
Feeder 2 (Short Needles)
34
Rib Camming
Dial Needle
/
I
swingcam
Guard Cam
-
35
Clearin Cam
(Tuck dight)
Dial Cam Section
Numbers 1 and 2 show the location of cams which change needles from inoperative position to
tuck position.
Numbers 3 and 4 show the location of swing cams which work along with the tuck cam to take
needles up to knitting position.
Numbers 5 and 6 show the location of adjustable stitch cams controlling the size of loops.
L
SwingCam3
SwingCam 5And6
.
short
Needle
Swing
Cam
(In Action)
/
ShortNeedle
(In Action)
/
/-
/
I
7a
Tuckcams’
Long Needle
Tuck Cams 2
(OutOf Action)
LongNeedle
Swin Cam4
(Out8 f Action)
36
Timing
CYL TRICKS
I.
CLEAR
Cast
DELAYED TIMING
SYNCHRONIZED
ADVANCED
TIMING
TIMING
-Dasned line depicis cylinder needle pathSolid line depiz:s dial needies path
37
Ll
\ADVANCED
'V' Bed Rib
38
1 x 1 Rib
39
40
E. Rib Fabric Characteristics:
a. Simple Ribs:
1x1
2x2
3x3
2x1
Half Cardigan
Full Cardigan
41
Thermal
Modified
F. ComplexRibs:
a. Plain:
Interlock
Single Pique’
42
Ponte-de-Roma
Swiss Double Pique’
Milano Rib
b. Relief
Cords
43
t
Blisters
c. Flat Jacquards:
2 Color
3 Color
5. Fabric Packaging And Handling Considerations:
44
6. Purl Fabrics:
A. Fabric Classifications:
a. Plain
b. Fancy
B. Knitting Action:
7. Hosiery:
A. Indentification And Knitting Sequences:
B. Machinery Classifications And Overviews:
a. Rotary
b. Reciprocating
--
~
c. Mechanical
d. Electronic
e. Jersey
f Ribfir1
45
1 x 1 Purl
Face course
Back course
46
Stitching
f-
i
---
5#Plain
I -
C
1
2
B
3
47
I
4 (Rib)
--
I
Half-Hoser
48
C. Machinery Vs. Product Classifications:
D. Shaping:
E. Pattern Capabilities:
F. Trends:
G. Special Considerations In Hosiery:
49
8. Machinery Developments And Purchasing Considerations:
A. Developments:
B. Considerations:
a. Cost
b. Reputation
c. TrialResults
d. Automation and Patterning
e. Warrantees, Maintenance and Service
f Productivity and Quality
g. Creel Design
--
~
h. Diameter
50
I
i. Gauge
j. Feeds
k. Spreader
1. Training
m. Inventory
n. Set-up and Plant Requirements
0.
Cleaning System
p. Lubrication
q. Monitoring System
r. Feeding System
.-
s. Capacity And Doffing System
51
9. Production Calculations:
C. Productivity
53
I
Date:
Style:
Name:
Weft Knit Analysis
Yarn Type:
Yarn Count:
Courses Per Inch
Wales Per Inch
Reading 1
SamDle
Reading 2
Tech Face
Tech Rear
Reading 3
Reading 4
Reading 5
X
Loop Length And Run-In
Feeder Number
1
2
3
4
Reading 5
LOOP
Length
5
6
------
Diameter:
cut:
Total Needles:
Calculated Run-In:
54
11.Knit Fabric Defects
A. Barr6 - Horizontal bands following courses around the tube.
Yam count variations (count uniformity)
Twist yam tension variations
Wrong yam - size, color, blend level, twist direction
Uneven oiling or waxing of yam
Malfunctioning of storage or tape feeders
Crooked dial needle bed
Different stitch settings
Faulty cylinder or dial cam settings
Dirt, lint, yam fragments in the cam system, tricks, needles
or sinkers
Improper threading of yarn
Faulty take down-spreader system
Machine vibration
55
B. Vertical Lines - Following the wales up the length of the tube usually mechanical.
Broken needles
Bent needles - stem, hook - sinkers
Dirty needles
Bent or stiff latches
Closed latches
Worn tricks - needles, sinkers
Dirty tricks - needles, sinkers
Dial and cylinder needle misalignment (timing, gaiting
problems) - needles rub
Improper setting of yam guides
Machine vibration
Spreader abrasiodcreasing
Improperly set spacers on take-up
Folds from too narrow spreading at take-up
Oil lines
Wrong needle
Mixed needle lots
56
C. Holes - Yarn or mechanical in nature.
High friction - between yam and guides
Insufficient wax o r oil
Poor quality (strength, elongation)
Too much yam tension
Knots
Improper yam size for gauge
Snarling of yam (twist lively)
Slubs, trash
Lint (low twist, extreme hairiness, poor cleanliness)
Low humidity
static
Improper setting of yam guides
Feeder problems (tight, rough places)
Faulty height adjustment of sinkers
Baa! c!6417;fl3
57
D. Stitch Runs - Random Or Continuous.
Yam tension too high (check yam path)
Yam snagging
Yam snarling - knots
Too high machine starting speed
Low yam tensions during running
Incorrect feeding of the yam
Inaccurate setting of distance between dial and cylinder
Improper take-down tension
Defective needle
Defective sinker
Machine vibration
58
I
E. Dropped Stitches
Improper setting of yam camer
Obstructed yam carrier
Improper needle timing between dial and cylinder
Twist liveliness of yarn
Bad needle (bent latch, hook)
Too tight of stitch (run-in or cam setting)
High yam tension
Too high of a dial height
Too high take-down tension
59