Combing Parameter
A precision adjustment measuring the vertical penetration of combing needles into the wool beard determines the efficiency of short-fibre removal in yarn preparation. Adjusting the top comb depth controls the level of combing that occurs as the cotton or wool is pulled through the machine. If the pins are set too high, short fibres will remain in the combed sliver, which reduces yarn strength and increases hairiness.
Setting this depth correctly is critical for producing fine, smooth combed yarns.
Fiber Cleanliness
The combing process removes small seed coat fragments, neps, and short fibres from the long-staple cotton beard. A deeper top comb depth forces more of these contaminants to be caught by the fine needles of the comb. This action produces a clean and parallel sliver that is ideal for high-speed spinning.
If the needles are set too deep, however, they can cause excessive fibre breakage and damage the machine parts. In addition, the resistance of the dense fibre mass can bend or break the fine steel pins of the comb, necessitating expensive part replacements and machine downtime.
Waste Management
Combing results in a percentage of discarded short fibres known as noil, which are collected for lower-grade textile applications. The top comb depth directly affects the percentage of noil generated during each cycle. Adjusting this setting allows the mill to balance yarn quality against material yield.
Mechanical Adjustment
Technicians use specialized dial gauges to set the height of the comb relative to the clamping nippers before starting a new batch. The top comb depth must be uniform across the entire width of the machine to prevent uneven combed sliver density. This calibration is checked at regular intervals during the production run.
Any variation across the combing head can result in weak spots in the spun yarn.
