Knitting Classification - Explain on Weft and Warp knitting

Knitting:

Knitting is a technique of constructing textile structures by inter-meshing loops of yarn which are formed with the help of needles.

There are two types of Knitting ,such as

Weft knitting
Warp knitting

1. Weft knitting:

Weft knitted fabrics can be produced in either flat or tubular form. Weft knitted fabric is generally highly elastic and highly drape able, two attributes, which make it suitable for a wide range of apparel applications. Weft knitted fabric is porous and comfortable both for outer garments and undergarments.

Four types of machines are available for weft knitting,

i) Circular knitting machine,

ii) Flat bed knitting machine,

iii) Fully fashioned knitting machine, and

iv) Hosiery knitting machine.

The circular knitting machine has a cylinder fitted with latch needles (the hooked needle and the thin strip of sinker separating two adjacent needles are fundamental elements of knitting machines). Synchronized timing cams fitting inside the cylinder guide the movement of latch needles in loop formation. The formation of a stitch on a weft knitting machine with a latch needle is shown in

below picture.

Stitch formation with a latch needle on a weft knitting machine, top to bottom:

Knitting: Knitting is a technique of constructing textile structures by inter-meshing loops of yarn which are formed with the help of needles. There are two types of Knitting ,such as Weft knitting Warp knitting 1. Weft knitting: Weft knitted fabrics can be produced in either flat or tubular form. Weft knitted fabric is generally highly elastic and highly drape able, two attributes, which make it suitable for a wide range of apparel applications. Weft knitted fabric is porous and comfortable both for outer garments and undergarments. Four types of machines are available for weft knitting, i) Circular knitting machine, ii) Flat bed knitting machine, iii) Fully fashioned knitting machine, and iv) Hosiery knitting machine. The circular knitting machine has a cylinder fitted with latch needles (the hooked needle and the thin strip of sinker separating two adjacent needles are fundamental elements of knitting machines). Synchronized timing cams fitting inside the cylinder guide the movement of latch needles in loop formation. The formation of a stitch on a weft knitting machine with a latch needle is shown in below picture. Stitch formation with a latch needle on a weft knitting machine, top to bottom: Formation of a stitch with a needle i) The closed needle after drawing off a loop. ii) The needle latch opens as the finished loop slips over it onto the needle stem. iii) The thread caught and being drawn by the descending needle head. iv) The previously finished loop pushes the latch closing the needle head while the new loop is formed. v) The first loop slips over the needle head onto the newly formed loop. 2. Warp knitting: In warp knitting, the work progresses length-wise, through the inter-meshing of loops in the direction of wale. In this process, all the loops on the knitting needles in the column remain in the knitting mode. The main advantage of warp knitted cloth is that, unlike weft knitted fabric, it is not easy to unravel. However, these fabrics are not as stretchable as the weft knitted fabrics. An example of warp-knit structure is shown in Fig. 1. Two types of warp-knitting machines are used: i) Tricot knitting machine, ii) Raschel knitting machine. Fig 1 : A Warp-knit structure

Formation of a stitch with a needle

i) The closed needle after drawing off a loop.

ii) The needle latch opens as the finished loop slips over it onto the needle stem.

iii) The thread caught and being drawn by the descending needle head.

iv) The previously finished loop pushes the latch closing the needle head while the new loop is formed.

v) The first loop slips over the needle head onto the newly formed loop.

2. Warp knitting:

In warp knitting, the work progresses length-wise, through the inter-meshing of loops in the direction of wale. In this process, all the loops on the knitting needles in the column remain in the knitting mode. The main advantage of warp knitted cloth is that, unlike weft knitted fabric, it is not easy to unravel.

However, these fabrics are not as stretchable as the weft knitted fabrics. An example of warp-knit structure is shown in Fig. 1.