Tuesday, May 28, 2019
WOVEN FABRIC LENGTH SHRINKAGE AFTER PROCESSING, WOVEN FABRIC LENGTH ELONGATION AFTER PROCESSING
WOVEN FABRIC LENGTH LOSS( SHRINKAGE OR SHORTAGE) AND LENGTH ELONGATION AFTER PROCESSING
The fabric shortage ( shrinkage ) after processing is always a disputed matter. When a fabric manufacturer approaches a fabric Dyer, the dyeing charge for a particular shade. The fabric dyer asks for a fabric manufacturer about a fixed amount of fabric shrinkage%( shortage) after dyeing of fabric. The matter of this fabric length loss gets fixed after mutual discussion between fabric manufacturer and dyer.
Now a question arises in everybody's mind that the fabric gets shrunk all time after processing. If it happens how much shrinkage does occur after processing actually. Is there any opposite action ( elongation) that takes place after processing? If you know what changes exactly occur after processing, you can reduce fabric cost by saving your fabric going unnecessary in your dyer account.
Reason for fabric shrinkage after processing:
1 - Sodium hydroxide ( caustic soda) is used in scouring the cotton fabric. When the caustic soda reacts with cellulose, the cotton fibres swell. This swelling of cotton fibres results in the form of fabric shrinkage. The Mercerisation process of the cotton fabric also causes little fabric shrinkage after processing.
2 - The type of dyeing machine also plays a decisive role in fabric shrinkage after processing. If the fabric is dyed under low tension or loose form, the chances of length shrinkage get increased.
If the fabric is dyed under tension like a jigger machine, the chances of shrinkage of fabric in length get decreased.
3 – The drying system is also a big concern regarding the shrinkage of fabric after processing. When the feeding length is more than delivery length, a much shrinkage percentage in fabric results.
If fabric drys on the drying range, the fabric shrinkage chances gets reduced.
If the fabric is dried on a relaxed drier, maximum length shrinkage results.
4 - Fabric weave also affects the fabric shrinkage after processing. The weave having a bigger float length shows high shrinkage percentage after processing.
REASON FOR FABRIC ELONGATION:
The fabric does not shrink in length all time after processing. It gets elongated much time after processing. When the fabric is dyed under tension conditions, it gets elongated.
Method of determining the shrinkage or elongation:
You should know the method how to determine the shrinkage% or elongation% after fabric processing. The picks per inch ( PPI) before and after processing is the one and only key factor which gives you the correct information about shrinkage or elongation. “If picks per inch are increased after processing, it indicates that fabric has shrunk in length after processing. If picks per inch are reduced after processing, it means the fabric has been elongated in the length”.
You can find out the correct percentage of shrinkage or elongation in length as below:
at May 28, 2019