Knitting and Technical Textile
An introduction of knitting technology and its applications in Technical Textiles by Dr. Muhammad Mushtaq Mangat Dec 9, 2012
Lecture 4 Contents Knitting technology explanations Knitting types Warp and weft knitting Application of knitted fabrics in Technical Textile
Knitting A type of fabric formation by using loop insertion into other loop.
Weft Knitting One major kind of knitting
Knitting Weft knitting
Only weft yarn is used to make loops,
Needles and sinkers are used to make loops and insert loops
Yarn is fed around right angle
No yarn sheet is made
Individual yarns are uses
Warp knitting
Yarn sheet (warp ) is made
Loops are made from warp and inserted along the warp length
Needles are used to make loops and insert loops across the warp
Warp knitted fabric is more rigid and many types are possible
More share in Technical Textile
[1]
Weft Knitting
Most common
More elastic fabric
Used for general clothing
Lot of variation in GSM and width is possible
Available in flat and circular shape
Weft Knitting Loop Description [1]
Knitting is one of several ways to turn thread or yarn into cloth. Unlike woven fabric, knitted fabric consists entirely of horizontal parallel courses of yarn. The courses are joined to each other by interlocking loops in which a short loop of one course of yarn is wrapped over the bight of another course. Knitting can be done either by hand, described below, or by machine. In practice, hand knitting is usually begun (or "cast on") by forming a base series of twisted loops
Knitting is a process in which one thread is used to make loops and then newly formed loops are passed through previously formed loops and top and bottom loops are joined with the help of head and feet
Knitting Fundamentals Basic Elements in knitting is Stitch or Course
Stitch Details
loop
Loop insertion through loop
Joining of two loops
Knitted fabric flexibility depends upon loop structure
Loops have many shapes and types
Loop
An extended portion of a regular string
Has no end
It is part of main string
Have balance shape
Is made with the help of any tool which is able to pull the string from a certain point
Loop Insertion
Loop is inserted through an other previously held loop with the help of needle
Needle should have the ability to hold fresh loop during insertion period
Needle is responsible to make new loops and hold the previous sloop
Loop insertion Animation
Knitting Cycle
Knitting Classification Based upon Knitting Procedure
Warp and Weft
Warp Knitting
Weft Knitting
Warp Knitting
In this process yarn sheet is developed (warp sheet) and then with the help of needles stitches are formed by insertion new loop into old loop.
Warp Knitting Machine
Warp Knitted Fabric
Weft Knitting
In weft knitting single yarn is fed to knitting needles. Needle with the help of cams, sinker make a new loop and passed it into previously held loops.
Types of Weft Knitting
Circular Knitting and Flat Knitting
Circular Knitting Machines
In circular knitting machines needles are fixed on a cylinder or dial in a circular shape.
There are more than one feeders to feed yarn to needles at different places.
In most of the cases needle bed (cylinder or dial) moves while feeders remain stationary.
Diameter of cylinder and dial is fixed but in case of sock knitting machines it is changeable due to structure of socks
Circular Knitting Machine
Flat Knitting Machines
In flat knitting machines needles are fixed on a straight plate. On this machine needle bed remains stationary while yarn feeding system called carriage moves from one end to other end
This machine is used to knit collars, arm bands and sweaters
Flat Knitting
Types of Circular Knitting Machines
Single Knitting
Double Knitting
Single Knit Machine
In these machines needles are fixed on cylinder and sinker are fixed on sinker ring. Needles knit with the help of sinkers.
Single Knit Machine
Double Knit Machine
In double knit machine needles are fixed on dial as well as on cylinders. There is no sinkers on this machine.
This machine is used to knit interlock, rib and double jerseys
Double Knitting
Double Knit Fabric Interlock--- Two sides are fully knitted, highly
flexible used for under garments. Front and back wales are exactly at same point
Rib--- two sides are fully knitted. Less flexible but have strong grip, used for neck, cuff opening and waist band. Front and back wales are not at same point
Double Jersey
Double side knitted, can have different designs on both sides
Interlock Machine
Double Knit Jacquard Knitting Machine
Types of Single Knitting Machines
Plain knitting
Loop knitting
Single Knit Plain Knitting Machines
Mostly called jersey machines. On this machines, there is a set of needles and sinkers. These machines may be single track of multi track. From one track to six track machines are available.
These machine can knit jersey, pique, honey comb, mini jacquard
Single Plain Knitting Machines
Single Track
Multi Track
Single Track Single Knit
Track means number of cams vertically fitted
In single track machine there is only one track
This machine can knit only full knit fabric (single jersey)
Multi Track Knitting Machine
In this machine there are 2-6 tracks
More number of tracks means that variety of designs can be produced
On these machine many types of fabric can be produced, like, pique, pique fleece, two thread fleece and mini jacquard
Loop Knitting Machines
In these machines we can make loop on one or on both sides of fabric.
By introducing loops we can increase the weight and bulkiness of fabric
Types of Loop Knitting Machines
Terry
Fleece
Terry Fabric
This fabric has loops on the surface, like towel but the length of loops is smaller than towels. Normally used to make shirts of kids or for people working under high temperature to absorb the moisture
Terry Knitting Machine
Terry Knitting Machine
Single Jersey Double Face Fabric
Three Thread Knitting Machine
This machine is used to produce fleece fabric. This fabric is plain from one side. Mostly front side is of single jersey and on back loop is inserted across various number of wales (normally two to three wales are covered).
Back side is brushed with the help of raising machine to make it more comfortable and bulky as well as warm
Two types of threads are used; fine for the top and course for back ( 30/16, 28/12 etc)
Three Thread Fleece Machine
Fleece Fabric
Striper
In stripe knitting machines we can produce horizontal stripes with the help of scissors which cuts the yarn and a new yarn is fed
There are two types of:
Mechanical
Electronic
Note: in current era there is no fresh production of mechanical strip machines
Stripe Knitting Machine
Jacquard Knitting Machines
These machine are available in single and double knit technology
Normally more than one colored yarns are used.
Different patterns are made
Normally 4-6 color machines are available
All types of machines can be converted into jacquard machines
Jacquard Machines
Mechanical Jacquard
Electronic Jacquard
Jacquard Fabric
Flat Knitting
Single bed
Double bed
Full Garment Flat Knitting Machines
These are latest machines and are used to make full length of garment
Quite expensive
Not in Pakistan
Required in countries where labour is expensive
Gloves Knitting Machine
Gloves Knitting machines
In this machine bed rotates and carriage moves from one side to other
Warp Knitting
Types of Flat Knitting
Raschel, made with latch needles,
Tricot, using bearded needles.
Warp-Knitting
When producing warp-knits, a yarn sheet is linked by stitches in longitudinal direction. Thus, each individual thread in the sheet (warp) forms a wale.
Warp Knitting
Main products Nets
Curtains Technical fabrics
Covers Covering sheets
Working Principle
Warp sheet
Loops development with the help of needles
Loops insertion with the help of needles
Needle movement controls mechanically and electronically
Properties of Warp Knitted Fabric
More stable than knitted
Big and small holes are possible
Many designs are possible
Highly course yarn can be used
Technical fabric can be produced
Use of Warp Knitted Fabric
Use to fulfill technical demands, like, filters, seat covers etc
Used as curtains, table covers
Used as Chadar in Pakistan
Not used for clothing
References [1] Anand, S.C., Technical fabric structures – 2. Knitted fabrics, in Handbook
of Technical Textiles A.R. Horrocks, Anand, S. C., Editor 2000, Woodhead Publishing Ltd Cambridge.