Indigo yarn has a good dry strength, smooth surface, high price but not easy to comb, breakage, high efficiency, low cost and so on in weaving weaving. In order to improve the product quality of the combing process, and to achieve economic production as much as possible, many manufacturers have carried out research and test on the process and equipment,
One method
Reasonable configuration parameters to reduce fiber damage caused by equipment
With the widespread use of high speed comber, the damaged fiber is inevitable. According to many years of production practice, the author believes that the following measures can be taken to reduce the degree of fiber damage.
First, improve the fiber straightness. According to the theory of fiber hook extension, the extension effect of the curved hook increases with the increase of the draft ratio. Therefore, it is helpful to reduce the tensile strength of the fiber in the cotton net and increase the fiber straightness of the sliver.
Second, the rational allocation of the pre drawing drafting process. To fully eliminate the hook should be the main draft control in the following 3.3 times, the drafting of 1.75 times ~2 times, draft 5 times ~6 times, and root number of 5 root ~6 root, large master drawing distance, increase the fiber shift point to the distance between the front roller nip, may be appropriate to reduce the pre and speed. Before the extension hook straight time.
Third, the rational allocation of strip and roll process. Because of the fiber shape of the cotton fiber hook of the feeding and winding machine. Therefore, the procedure should be adopted more and increase the total number, draft ratio, improve the fiber straightness; at the same time, it should be a reasonable set of small volume starting pressure and increasing pressure amplitude, avoid licking.
Fourth, a reasonable choice of the cylinder before a few needle teeth angle, tooth density and hardness. The working angle is too small, in the hands of about 60 degrees, in order to facilitate the needle tooth must pierce plexus, pre opening; the pin gear hardness should be more than HV800, in order to reduce the broken needle and crooked needle, needle teeth and tooth profile to avoid damage to the fiber gap is too small; tooth density should not be too large, master in 25 the tooth / cm left and right, in order to reduce the damage to the fiber.
Fifth, the reasonable choice of forest speed. Carding speed constant speed rotating cylinder is decreased in the carding process, namely the cylinder before a few needle teeth start comb speed is the largest, so the cylinder speed should not exceed 350 clamp times / min; carding speed variable rotating cylinder can be from slow to fast, then from fast to slow alternate change.
Method two
Optimization of mechanical mechanism to improve the CV value of combed sliver
In the actual production, many enterprises often meet to improve the production efficiency by increasing the speed of combing machine. In particular, when the traditional comber, when the speed increased to 400 times more than clamp / minute, the stem will appear to varying degrees of deterioration. We are in the JSFA388A comber on the main body or parameters are optimized, and the spinning test, analyze the transmission mechanism and the relationship between evenness CV value, provide a reference for the technical renovation of the combing quality control and combing machine.
Through the experiment, we found that the technical measures to improve the JSFA388A combing machine mainly include the following aspects.
First, spinning cotton, fine cotton, cotton net lap scale were 1.75 and 1.25 when the evenness is better. Therefore, the production of cotton lap net scale should be adjusted in length according to the cotton fiber near a better position, the principle of the main fiber length decreases, move to smaller scale direction; conversely, the scale is too large to adjust the direction.
Second, the driving mechanism of detaching roller is optimized, cotton cluster overlap rate increased by 6.77 percentage points; when the combing speed is 400 times / min clamp, evenness CV value decreased from 3.87% to 3.32%; the separation roller motion law is more reasonable, the velocity and the acceleration of the corresponding low, stable operation of the machine also improved.
Third, combing machine with the upper and lower five curve drawing mechanism, in the combing speed of 400 times / min, the draft number of hours, combed the stem can maintain a good level, but the adaptability of the high speed is poor. Three the upper and the lower pressure bar drafting mechanism can effectively control the speed change point of the fiber, which is beneficial to the improvement of the combing sliver, and is more suitable for the combing process of the heavy weight, high speed, high draft and forward feed cotton.
Fourth, to improve the sliver conveying mechanism and adjust the position of the guide bar, which is helpful to eliminate the overlapping mechanical wave and improve the evenness.
Method three
Temperature and humidity control reasonably reduce carding noil rate
In the face of today's market crisis, spinning enterprise profit space of many adverse factors seriously squeezed, cotton costs accounted for more than 70% of the total cost, to ensure customer requirements of yarn quality under the premise, only scientific and reasonable to reduce noil rate, can better improve the enterprise profit.
The temperature and humidity of different influence on cotton fiber processing, when the temperature and humidity is low, the actual amount of water vapor in the air is low, the air is dry, brittle fiber, process prone to breakage, easy to produce static electricity, flying more difficult life, manifested in the carding process is a sharp increase in the rate of short fiber, resulting in dramatic fluctuations of noil rate. After repeated tests found in temperature and humidity under different temperature, when humidity is low, the increase of 1~1.5 percentage points of noil rate than normal state. Similarly, the temperature and humidity control can not be too high, because the air is too humid, the effect of removing impurities in cotton neps is reduced.
It is worth noting that the combing process of temperature and humidity regulation can not be one-sided pursuit of temperature and humidity indicators, not only for temperature and humidity indicators and regulation, but should be combined with the actual effect of production to master. In fact, when the temperature is higher, the relative