What is Combing?
The Laps are then taken to a stand and kept to be moved to the combing machine.The lap length and weight is constant through out unless it is set for a different specification.The operator moves the trolley near the comber machine and brings the empty trolley kept near combers,when the laps are taken from the trolley to feed the comber machine. Several operations are performed one after another continuously including cleaning of the Comber segment in perfect order. It Draws the Lap to form a sheet of web, breaks it to set length, allows it to be combed by the comber segment which consists of needles like in a comb that we use to comb our hair.The Comber removes short fibers that do not help in making a fine yarn and a brush cleans the comber and the suction device takes out the short fibers, like we clean our comb on a hand towel.
As soon as combing is complete the sheet of web comes oner a plate and gets condensed to form a sliver, the pre and post broken sheet of web are joined by a forward and backword moving pair of fluted rollers at the bottom and rubber covered rollers at the top which grip the sheet of fine web which looks like a bridal veil. 8 such Comber segments form one machine and even 16 segments may form a machine known as double sided machine. The short fibers known as comber noils are very clean and they are graded as first grade waste and may also be used for spinning very course yarns like 6's and 10's. The slivers known as combed slivers are fed to a Drawing machine since the combing gets fibers crisscrossed at many places and needs to be made parallel before they are taken to Fly Frames for conversion to go to spinning, a pre spinning operation.
Objectives of Combing
Following are the objectives of combing process:
- To remove the fiber shorter than a predetermined length.
- To remove remaining impurities in the comber lap.
- To remove naps in the carded sliver.
- To make the fiber more parallel and straight.
- To produce a uniform sliver of required per unit length.
Necessity of combing
The following quality of fibers can only be obtained by combing
- Clean finer fiber
- Uniformity in length of fiber
- Absence of nap
- More parallel arrangement of fibers
- Straight fibers
Combers Noel: The wastage which is removed from the comber m/c during processing is known as comber’s noel. It is expressed as percentage. It is mainly of short fibers and naps. Noel is used for lower count as raw material.
For getting high quality of yarn, one extra process is introduced which is called combing process.Combing is an operation in which dirt and short fibers are removed from sliver lap by following ways.
- In a specially designed jaws, a narrow lap of fiber is firmly gripped across its width
- Closely spaced needles are passed through the fiber projecting from jaws.
Short fiber which we remove is called comber noil. The comber noil can be recycled in the production of carded yarn. Yarn which is get from comber sliver is called comber yarn. Carded sliver are combine into comber lap in a single continuous process stage. Flat sheet of fiber which is get from comber lap is fed into the comber in an intermediate.There are different ways by which value of combing is used in the manufacturing of cotton. By spinning point of view combing process makes more uniformity in the yarn. Strength of yarn is also high because in combing process short fiber are removed and only fiber having good strength remains. So it play very important role for increasing the yarn strength. Because of straightened condition of fibers combing makes possible spinning smoother and more lustrous yarn. In combing process length of fiber are strong so it need less twist produced then carded yarn.