Knit fabric is produced from loop formation. So it needs to be careful during production. Different types of faults could be found in knit fabric, which could be the cause of fabric rejection. If we can find out the defects of fabric during production, than we can take steps to remove it from the next knitting production process.
In practical; following knitting faults could be found in the knit fabric. Some knitting faults and their remedies are given bellow:
- During loop formation the yarn breaks in the rejoin of the needle hook.
- Holes are the results of yarn breakage or yarn cracks.
- If the yarn count is not correct on regarding structure, gauge, course and density.
- Badly knots or splicing.
- Badly set of yarn feeder.
- When a needle breaks down then needle marks come along the fabrics.
- If a needle or needle hook is slightly bends then needle mark comes on the fabrics.
- Buckling of the needle latch.
- Yarn tension variation during production.
- Low G.S.M fabric production.
- When sinker corrodes due to abrasion then sometimes it cannot hold a new loop as a result sinker mark comes.
- If sinker head bend then sinker mark comes.
- If yarn is not properly feed during loop formation.
- Use of defective needle.
- Too loose of take down mechanism.
- If yarn tension is insufficient.
- If yarn feeder is badly set.
- When oil lick through the needle trick then it pass on the fabrics and make a line.
- If any rush in the machine.
- Pin hole may come to fabric due to break down or bend of the latch.
- Improper greasing in the machine
- IF greasing is excess.
Cloth Fall Out
- Cloth fall out can occur after a drop stitch especially when an empty needle with an empty needle with close latch runs into the yarn feeder and remove the yarn out of the hook of the following needles.
- Yarn fault is responsible for this fault.
- If different micro near value of fiber content in yarn.
- Different luster and dye affinity of fiber content in yarn.
- During spinning different similar classes of fiber is mixed specially in carded yarn and these fibers have similar characteristics.
- In draw frame different similar classes sliver is mixed and make one sliver.
- If yarn contains foreign fiber then it remains in the fabric even after finishing.
- Lot mixing and count mixing is responsible for these faults.
- In knitting section too much lint or short fiber is flying to and fro that are created from yarn due to low twist as well as yarn friction. This lint may adhere or attached to the fabric surface tightly during knit fabric manufacturing.
Causes: Different yarn faults also are cause for knitting faults.
- Yarn count variation
- Thick/Thin place in yarn
Now, if we want to remove these knitting faults we should be aware before yarn selection and during knitting of fabric. Knitting machine conditions should be perfect. Needle, Sinker, Feeder and other equipments, which is used, should be fault free.
So, Management related person should be aware about the causes of knitting faults and try to reduce the knitting faults.