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
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