Experiment No: 09 Date:21st July, 2014

Experiment Name: Analysis of some common knit fabric faults & their Remedies.

Some common knit fabrics foults & their remedies are given below:

1.Needle Broken:

Needle broken is a common knit fabric fault.This cause & remedies are given below-

Cause:

a) Due to dirt deposition in needle problem occurred.

b) This problem also occur due to yarn tension variation.

Remedies:

a) Yarn tension have to minimize.

b) Needle must be cleaned before production of any new fabric.

Figure:

2.Thik &Thin:

Thik & Thin is another fault of knit fabric.

Causes:

a) Its due to yarn problem

b) This fault is responsible for yarn thik & thin place.

Remedies:

Ensure that yarn is fine as well as no thik & thin place.

Figure:

3.Pin Hole:

Cause:

a) Improper tension.

b) Same drive for both knit & tuck stitch.

c) Curved needle latch.

Remedies:

a) Different drive have to maintained.

b) Needle has to change.

Figure:

4.Broken Needle:

Defeets caused by the broken needle show prominently as vertical lines parallel to the wales. There are no loops formed in the wale which has a broken needle.

Cause:

a) High Yarn tension.

b) Bad setting of the yarn feeders.

c) Old & worn out needle set.

d) Breakage of hook or butt in needle.

Remedies:

a) Ensure uniform is the right yarn tension on all the feeders.

b) Keep the recommended gap brtween the yarn feeders & the needles.

c) Remove fly or blockage from grove.

Figure:

5.Drop Stitches:

Drop stitches are randomly appearing small or big holes of the same or different size which appear as defects in knitted fabric.

Causes:

a) Slight yarn tension.

b) Yarn over feed or underfeed.

c)Defects like slubs,nepsmknot etc.

d) High fabric take down tension .

e) Incorrect gap between the dial is cylinder.

Remedies:

a) Ensure uniform yarn tension on all the feeders with the feeders with a tension meter.

b) The yarn beign used should have imperfection like slubs,neps etc.

c) The gap between the cylinder & the dial should be correctly adjusted as per the knitted loop size.

Figure:

6.Barrines:

Barrines defect appears in the knitted fabric in the form of horizontal stripes of uniform or variable width.

Causes:

a) High yarn tension.

b) Count variation.

c) Mixing of the yarn lots.

d) Package hardness variation.

Remedies:

a) Ensure uniform yarm tension on all the feeders.

b) Ensure that the yarn beign used for knitted is of the same lot.

c) Ensure that the hardness of all the yarn package is uniform using a hardness tester.

Figure: