Recently, many articles on carding machine do technical analysis, which must be qualitative and quantitative analysis. Although this article is short, it is very good in qualitative analysis. In quantitative analysis, the figures listed in it also have certain reference significance.

1. Enhanced carding

Enhanced carding can straighten the fiber, decompose into single fiber, and promote the separation of the fiber from impurities, but also to release the knot. Therefore, the precision of the main carding distance and the sharpness of the carding element are very important.

2, in addition to miscellaneous to reasonable division of labor

Grasps what impurity in what process and place is the most advantageous, that is to eliminate impurity should be reasonable division of labor, card itself each part to remove impurity should be reasonable division of labor. For the impurities which are generally large and easy to separate and eliminate, the principle of falling early and breaking less should be carried out, and falling early in the opening and cleaning process. It is more advantageous to remove the impurities with high adhesion, especially the impurities with long fibers, on the card. Therefore, when the maturity of raw cotton is poor and the harmful defects of belt fiber are more, the impurity removal and blanking of card should be increased appropriately. The card roller part should eliminate broken seeds, stiff petals and short lint, as well as fine impurities with shorter fibers. Cover plate is suitable to eliminate fine impurities and cotton knots, short lint, etc.

For general domestic cotton, the total drop rate of carding cotton is greater than the opening cotton. The impurity removal efficiency of cleaning cotton (containing impurity in raw cotton) should be controlled at 50%-65%, the impurity removal efficiency of carding roller part (containing impurity in cotton coil) should be controlled at 50%-60%, the impurity removal efficiency of cover plate should be controlled at 3%-10%, and the impurity rate of strip should be generally controlled below 0.15%.

The key point to control the impurity in the card is to adjust the process parameters of the small leakage bottom and the dust cutter, such as the inlet spacing of the small leakage bottom and the fourth spacing, the height of the dust cutter and so on. When the raw cotton maturity is poor and the roll contains more impurity, resulting in the increase of the strip containing impurities, should be a small leakage bottom entrance distance, increase the length of the drop of miscellaneous area to be adjusted. The straw on the roller cover should not be blocked, otherwise it will make the belly after the abnormal cotton fall, white increase. The string length of small leakage bottom is too long, and the specification of bayonet tooth is not suitable, etc., which will increase the number of impurities in the strip. The size of the needle cloth, the distance between the front cover plate and the cylinder plate, the position of the top of the front cover plate and the speed of the cover plate also affect the number of impurities and knots in the strips.

3. Reduce rubbing

The knot produced on a card is mainly formed by reflowering, winding, and rubbing of fibers. For example, if the spacing between cylinder and doffer, cylinder and cover is too large and the needle tooth is blunt, the fiber is rubbed too much, as well as the return of the roller and the winding of the cylinder will increase the knot. Serious winding in opening and cleaning process, high moisture regurgitant of cotton rolls, too large mixing ratio of recycled and reused cotton or uneven feeding will increase the slippage.

Reasonable cotton distribution and strengthening temperature and humidity management have considerable effect on reducing knot and impurity. Several indexes, such as maturity, harmful defects and impurity, which have great influence on yarn forming and impurity in cotton blending, should be strengthened to control the difference of their indexes. When the moisture regain of raw cotton and cotton roll is low, the impurities are easy to fall, and the cotton end silk can also be reduced, so the moisture regain of cotton roll should be controlled not more than 8%-8.5%, and the raw cotton not more than 10%-11%. Control carding workshop low relative humidity, such as relative humidity control in 55%-60%, make it wet, and increase the rigidity and elasticity of fiber, reduce fiber and cloth friction and congestion. However, if the relative temperature is too low, it is easy to produce static electricity, and the cotton netease is broken, adhered or broken. Especially when spinning chemical fiber, this phenomenon is more obvious. If the relative humidity is too low, the moisture regain of the strip will be reduced, which is unfavorable to the later drafting process.

Adopting alloy copper needle cloth, strengthening the function of carding, and increasing the suction point and air suction rate on each card can reduce the filth and impurity to a great extent.