1 Enhanced carding
Enhanced carding can straighten the fibers, decompose them into single fibers, separate the fibers from impurities, and loosen neps. Therefore, the accuracy of the main carding distance and the sharpness of the carding elements are extremely important.
2 Removing impurities requires a reasonable division of labor
Know what impurities are in what It is most beneficial to drop down the processes and parts, that is, there must be a reasonable division of labor to eliminate impurities, and there must also be a reasonable division of labor to remove impurities in each part of the carding machine itself. For impurities that are generally large and easy to separate and remove, the principle of falling early and breaking less should be implemented and dropped early in the cleaning process. Fiber impurities with greater adhesion, especially long fiber impurities, are more advantageous to eliminate on the carding machine. Therefore, when the maturity of raw cotton is poor and there are many harmful fiber defects, the carding machine should be appropriately increased to remove impurities and waste. The licker-in part of the carding machine should eliminate broken seeds, stiff flaps and short lint, as well as small impurities with shorter fibers. The cover is suitable for removing small impurities, neps, short lint, etc.
For general domestic cotton, the total noil rate of carding cotton is greater than that of blowroom cotton. The impurity removal efficiency of cleaning cotton (containing impurities in raw cotton) should be controlled at 50%-65%, the impurity removal efficiency of the carding roller part (containing impurities in cotton rolls) should be controlled at 50%-60%, and the cover plate should remove impurities The efficiency is controlled within the range of 3%-10%, and the impurity content of the raw sliver should generally be controlled below 0.15%.
The focus of impurity control on the carding machine is the licker-in part. In production, the process of adjusting the small leakage bottom and dust removal knife Parameters can be used to achieve this, such as the small drain bottom inlet spacing and the fourth point spacing, the height of the dust removal knife, etc. When the maturity of raw cotton is poor and the cotton roll contains more impurities, resulting in an increase in the impurity content of the card sliver, adjustments should be made by adjusting the spacing between the entrance to the leak bottom and increasing the length of the impurity area. The suction tube on the licker-in cover should not be blocked, otherwise it will cause abnormal cotton waste and increase white waste on the rear belly. The chord length of the small leakage bottom is too long, the teeth of the licker-in are not suitable, etc., which will increase the impurity content of the card sliver. The card clothing specifications of the cylinder and the flat plate, the distance between the front upper cover plate and the cylinder, the height of the upper front cover plate and the flat plate speed, etc., also affect the impurity content of the card sliver and the number of neps.
3 Reduce rubbing
The neps produced on the carding machine are mainly due to return, twisting and fiber rubbing. And formed. For example, when the distance between the cylinder to the doffer and the cylinder to the cover plate is too large and the needle teeth are blunt, the fibers will be rubbed excessively. Also, if the licker-in and the cylinder twisting will increase the neps. Severe winding in the blowroom process, too high moisture regain of cotton laps, too large mixing ratio of recycled cotton and reused cotton, or uneven feeding will all lead to an increase in card sliver neps.
Rational distribution of cotton and strengthening temperature and humidity management can play a significant role in reducing neps and impurities. Several indicators that have a greater impact on yarn knotting during cotton blending, such as maturity, harmful defects, impurities, etc., should be strengthened to control the differences in indicators. When the moisture regain of raw cotton and cotton laps is low, impurities are easy to fall, and the cotton end yarn can also be reduced. Therefore, the moisture regain of cotton laps should be controlled not to exceed 8%-8.5%, and the moisture regain of raw cotton should not exceed 10%-11%. Control the lower relative humidity in the carding workshop, for example, control the relative humidity at 55%-60% to dehumidify, increase the rigidity and elasticity of the fiber, and reduce friction and congestion between the fiber and the card clothing. However, if the relative temperature is too low, static electricity is easily generated, and the cotton mesh is easily broken, adhered or broken. This phenomenon is more obvious especially when spinning chemical fibers. If the relative humidity is too low, it will also reduce the moisture regain of the card sliver, which will be detrimental to the subsequent drafting process.
Using high-quality alloy copper card clothing to strengthen the carding effect and increase the dust suction points and suction points on each carding machine. Air volume can reduce the knotting of raw slivers to a great extent. </p
