Textile Technology: How To Reduce Combed Fiber Damage

In the face of rising raw material costs and low profits, enterprises in the combing process are more concerned about reducing the cost of raw materials in combing processes. < p >

The loss and damage of effective fibers are of great significance for controlling the rate of noil and compromising production cost.

Mastering the gradient configuration and appropriately increasing the rack density in the back area can eliminate smaller neps, improve the single degree of cotton fiber, improve the removal efficiency of small neps and short fibers, reduce fiber damage, and improve the overall quality of yarn.

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< p > < strong > combing preparation: reasonable adjustment of parameters to ensure combing unwinding < /strong > < /p >

< p > < strong > Shandong Liaocheng < a href= "http://www.91se91.com/news/index_c.asp > > Huarun textile < /a > Co., Ltd. Liu Yunguang < /strong > /p >

< p > combing preparation process design priority is to increase the degree of parallelism, straightness and separation of cotton fiber, which is not adhesion and fiber damage during the process of combing, and is conducive to saving cotton.

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< p > < strong > choose the suitable drafting multiple < /strong > /p >

< p > the selection of drawing parameters for pre drawing should satisfy the extension of the crooked hook fiber as far as possible, so the selection of draft ratio in the back zone should be larger, which is more conducive to the extension of the front crooked hook fiber.

The number of combined roots of the pre drawing machine is 5 to 6, which is more suitable.

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The selection of the parameters for the P drawing should be as far as possible to meet the extension of the rear crooked fibers. Therefore, the draft ratio in the back zone can be chosen 1.032 times smaller than that in the draft area, which is mainly due to the increase of the draft ratio in the main draft area, which is more conducive to the extension of the back crooked fibers in the main draft area.

It is advisable to increase the number of the root of the sliver on the bar coiler, generally 26 to 28, so as to increase the evenness of the rolls.

The total drawing ratio of strip coiler should be controlled within 1.6 times as much as possible.

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< p > the total drawing ratio of the combing preparation process should be controlled 7 times to 8.5 times.

This is because the total drafting ratio is small, and the fiber straightness and parallelism will lead to the increase of medium length fiber in combed noil.

The greater the drafting ratio, the better the elongation of fiber yarn and the reduction of friction between fiber and fiber.

When separating and joining, when positive fibers are drawn out of a large number of negative fibers, the strength of some fibers that are attached to the positive fibers will be greatly reduced due to the friction between the fibers and the pverse connection between the fibers. Therefore, the self cleaning ability of the cotton rolls is reduced, which is not conducive to the removal of Neps in the combing and separating stage.

The total draft multiple is too large, and the yarn hairiness is increasing. Meanwhile, the probability of cotton layer adhesion is greatly increased during the process of combing and unwinding.

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< p > properly enlarging the distance between the pre drawing frame and the roller roller can increase the distance from the point of change of the fiber to the front jaw, and we should try to find the best technological parameters to reduce the NEP and short staple rate of the sliver through experiments.

This is because the small drafting roller spacing can make the yarn get a good CV% value, but it can not get the best comprehensive quality. It may bring some negative effects such as the damage of long fibers, the increase of combed sliver content, the increase of combed noil rate and the increase of yarn quality.

Therefore, the design of the drawing distance of the pre drawing frame and the bar winding machine should be 1 millimeters to 2 millimeters larger than the normal design.

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< p > small volume should be mastered. It can not only meet the carding requirements of Xilin, but also improve the grip strength of the clappers.

When the clamp plate opens, the elasticity of the cotton bushes will increase, which will be beneficial to the lifting of the cotton bushes and the separation and joint. It will also help the comber to reduce the hole, the edge and the broken web of the output web when the comber is running at high speed.

The greater the fiber quality, the greater the friction between fibers and fibers. The better the self cleaning effect of cotton rolls is.

The so-called self cleaning effect of cotton rolls is actually the self cleaning effect of the whole process of separating draft under the action of top comb.

The yarn quality in practice shows that in the same combing rate, the yarn quality of 75 grams / meter is smaller than that of 65 grams / meter.

In general, the small rolls of fine staple cotton are 75~80 grams / meter long and 68~72 grams / metre long staple cotton.

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< p > when the combed small volume is lighter, the number of carding teeth on each fiber increases, and the carding effect of Xilin needle teeth on fibers increases, and the carding degree increases, so that the rate of combed noil increases.

When the small volume is reduced from 72 g / m to 60 g / m, the percentage of combed noil can be increased by 0.4% to 0.5%.

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< p > < strong > timely adjustment of equipment < /strong > < /p >

< p > coil pressure can be achieved by adjusting the taper of the compression rod.

Whether the selection of the roll pressure is suitable can directly affect the degree of sticky roll.

Too much pressure causes the external force to be greater than the cohesion between the fibers. It is easy to occur between the cotton layer and the fiber. The low pressure will cause the structure of the cotton roll to relax and not suitable for production.

It is necessary to select suitable roll forming pressure for different cotton pads, so as to prevent rolling and surface hair falling.

If the volume pressure is not suitable, it will cause different degrees of sticky and surface hair.

The pressure of the general spinning G88 and PIMA varieties should be larger, and the pressure of the Xinjiang cotton is smaller.

The initial pressure was controlled in 1.2 PA to 1.8 PPA, the end pressure was controlled in 3.5 PPA to 4 PA, and the appearance of the cotton roll and the hand feel should be observed at any time. There should be no clear stripe in the front.

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< p > the surface of cotton sliver, such as cots, rolls, rollers, clamps, etc., should be smooth, burr free and attached to prevent sticky, twining and hanging fibers, thereby inducing fiber disorders.

Especially in high temperature and high humidity season or high sugar content in raw cotton, we should promptly remove the appendages such as cotton wax and impurities from the roller and the roller, so as to ensure that the fibers are not sticky, entangled or hung.

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< p > attention should be paid to adjusting the opening size before feeding, as far as possible, misplacing and stacking feeding, laying evenly and keeping uniform, and not having uneven thickness on both sides.

The opening and closing of the two ends of the chuck should be consistent, so as to ensure the consistency of the two ends of the chuck, so as to ensure the consistency of the two sides of the cotton roll, so that the side of the cotton roll can be formed well, the appearance is clean, the layers are clear, and the adhesion of the edges of the cotton rolls can be reduced.

On the one hand, excessive combination number and excessive drafting ratio can help improve the fiber's straightness, but on the other hand, it will also lead to excessive fiber parallelism, fiber fatigue and ripening of stripes.

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< p > --EndFragment-- > operation should be carried out according to the operation method. Each cotton sliver must be fed in the prescribed channel. It is strictly prohibited to add two cotton slivers in the same channel to avoid the sliver adhesion.

Keeping proper temperature and humidity in the workshop has an important effect on reducing the roll coils.

Humidity and temperature, the humidity has a greater impact on the fiber. When the temperature and humidity of the workshop are too high, the cotton wax and sugar will melt and produce adhesion. If the temperature and humidity are too low, the fibers will become slippery and hard due to the waxy quality, which will lead to a loose head.

Therefore, keeping the temperature and humidity suitable and stable, so that it does not produce large fluctuations, so that the moisture regain of fibers is maintained at the best condition, and is particularly important for preventing sticky rolls.

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< p > strong > combing process: optimize process configuration, protect effective fiber < /strong > /p >

< p > < strong > Shandong Liaocheng Huarun Textile Co., Ltd. Liu Yunguang < /strong > < /p >

< p > modern high efficiency < a href= "http://www.91se91.com/news/index_c.asp > comber < /a > in the design of separating roller mechanism, the pmission law of separation rollers is adopted in the design of the separation roller mechanism. At the same time, two kinds of optimization design are combined with the Xilin speed change carding (the end of the tin pin can be used to separate the nearest points of rollers), so that the range of adjusting the three rollers, the Xilin positioning process and the clamping plate closing timing process is enlarged, which effectively avoids the percentage of cotton net caught by the end pin of the cylinder in the machine, especially using the large angle or super angle carding surface of cylinder.

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< p > because E62 comber and combing machine previously produced do not have the function of combining the above two optimization designs. If three processes are not properly adjusted, it is very likely that the cotton net separated from rollers into the machine will be eaten up by the end pin of the cylinder. It will cause a sharp increase in the rate of droppings, resulting in the loss of effective fibers, especially the use of Xilin, which is 1110 of the tooth surface. This phenomenon is very easy to happen.

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< p > < strong > reasonable disposition of process parameters < /strong > /p >

< p > optimization of the positioning process of Xilin.

If the Xilin positioning process is too delayed, the cylinder end of the cylinder will touch the ends of the separation plexus at the tightest point of the separation roller so that the cylinder needle will take away the fibers in the separation plexus.

However, the carding stage of the cylinder at 1110 of the tooth surface is 12.5 degrees, which is 2.9 times longer than that of the 900 cylinder cylinder. Therefore, the probability of separating the cotton net from rollers into the cylinder is greatly increased.

The Xilin positioning technology adopts 36 degrees to meet the conditions that tin and cotton nets are not caught by the end pin of Xilin.

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< p > optimization of separation process of roller.

The longer the separation time is, the smaller the absolute value of the front inversion is. The shorter the length of the cotton net separated from the rollers, the easier it is to catch the cotton net from the end of the cylinder.

Therefore, in order to reduce the combed noil rate and reduce the loss of effective fibers, the rotation time should be delayed from the rollers, which can be adjusted in the range of 16~17 degrees. The overlap value in the head should be adjusted to -2 direction, which is more conducive to saving cotton.

Spinning experience shows that when the long staple cotton is spun, the matching line of the combing machine corresponds to about -0.3, and the corresponding value of the fine spinning cotton variety should be about 0, and the yarn quality index is better.

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< p > clamp plate closure timing optimization.

The clamp plate closure time is early, the clamp plate opening is late, the opening quantity is small, the closing time is delayed, the opening is early, and the opening quantity is large.

The closing time of the clamp plate should be earlier than that of the Xilin combing. Otherwise, the effective cotton stem cluster in the nipper jaw should be grabbed by the front pin of Xilin to form combed noil.

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< p > the combing machine on the E62 comber adopts a 1110 cylinder combing cylinder. The Xilin positioning process is 36 degrees. The clamp plate closing time is 34.7 degrees. The first cylinder of Xilin reaches the 34.2 degree of the lower edge of the clamp plate, while the opening of the nipper at the front position is 21 millimeters.

When the clamp plate is closed at 33.7 degrees, the position of the original comb point is still 34.2 degrees. The opening position of the corresponding position of the clamp plate is 19.5 millimeters, which can satisfy the condition that the cylinder is not caught by the front pin of the cylinder when it starts to comb. Therefore, when the tooth face angle is 1110, the cylinder opening of the nipper is reduced at 36 degrees, the loss of effective fibers can be reduced, and the rate of combed noil will be reduced.

However, the opening quantity can not be too small, otherwise it will cause the separating plexus to break away from the top comb needle too early, which will affect the carding efficiency of the top comb and the rise of the fiber when it is separated and combined.

Therefore, the opening quantity of the clamp plate can be controlled in the range of 19.5 to 20 millimeters.

If the comber has no nipper opening control mechanism, its opening quantity can be adjusted by eye.

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< p > < strong > severe inlaid injury fibers < /strong > < /p >

< p > test showed that when combing Xilin seriously inferior to a href= "http://www.91se91.com/news/index_c.asp" > mosaic flower < /a >, the combed noil rate would be reduced by 0.25% to 0.45%.

This is because when the cylinder is seriously inlaid, combing tin forest can not effectively comb the fibers.

The impacted short fiber will produce severe extrusion and friction to the effective fibers held by the nipper, and tear off the effective fibers. The fibers can not be effectively combed, and the combed sliver and NEP can not be effectively eliminated, so that the yarn quality deteriorates.

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< p > < strong > optimal arrangement of rack density < /strong > /p >

< p > embedded sawtooth monolithic cylinder has strong spinnability and has been widely applied.

In order to ensure the maximum carding efficiency of Xilin, it is necessary to reasonably configure tooth density in the limited cylinder grooming interval, such as improper configuration will cause damage to effective fibers.

For example, the density of the front area is too thin, which will increase the burdens of the rear area and easily cause the inlay of the rack in the back area, which will eventually lead to the damage of the cylinder. The over density will directly cause the fiber damage, because the total combing point is too large, because the blade is too thin, the strength is too low, and the service life of the cylinder rack is sharply shortened, which eventually leads to fiber damage.

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< p > therefore, reasonably increasing the rack density of the front carding area can strengthen the puncture, grabbing and loosening of the rack in the front area. At the same time, it is also necessary to avoid the oversize rack arrangement in the front area and reduce the carding efficiency of the carding area, resulting in the phenomenon of breaking and breaking holes in the cotton web when the comber is in the high-speed output state.

For example, German schle company optimized the angle of needle teeth and the density of needle teeth. The density of the front two rack of 90 series combing cylinder was 900 teeth / cubic centimetre and 62 teeth / cubic centimeter. The carding density was increased by changing the rack density of the back area. The maximum carding point of this series of Xilin was only 30305 points, while the new two series of Xilin 96 series were 53 teeth / cubic centimeter, 88 teeth / cubic centimeter, and the maximum carding point could reach 38980 points.

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