Process configuration and application effect of th

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Process configuration and application effect analysis of domestic iron gun free computer roving frame

the domestic iron gun free roving frame cancels the cone wheel and its control mechanism and forming mechanism of the traditional roving frame. It has the functions of computer monitoring and variable spindle speed spinning. It was first exhibited at the 1996 Beijing International Textile Machinery Exhibition and has been put on the market in batches. Combined with production practice, this paper introduces the process configuration of iron gun free roving frame and the test and analysis of key quality technical indicators (taking FA425 roving frame as an example)

1 main technical features

1.1 computer control system

adopts computer control system, cancels the cone wheel and its control mechanism and forming mechanism of traditional roving machine, simplifies the mechanical structure of the whole machine, reduces mechanical and process adjustment points, and is conducive to reducing the failure rate. Due to the use of computer-controlled variable-frequency speed regulation drive, the winding speed and the output speed of the front roller can be well matched instantaneously in the whole spinning process of the drafting and winding transmission mechanisms, so that the roving tension can be stabilized in an ideal state, and the absolute value of the roving tension can only change in a small range, reaching an approximate constant tension spinning effect. In the spinning section from the front roller to the spindle cap, a CCD) roving tension detection device with a resolution of 0.1mm is set to transmit the signal of roving tension change (up and down shaking of the spinning section) to the computer system, which controls the frequency converter of each motor through the computer system, so that the main motor and winding motor drive each spinning part for spinning according to the spinning design requirements, And the up and down jitter of the spinning section does not exceed 0.1mm

1.2 other main technical features

the digital display touch screen is adopted, which can intuitively input and modify relevant parameters, and can call up and display various data of machine operation at any time according to the current situation. In addition, it can give an alarm in time for the failure of the machine operation and display the troubleshooting methods. It can also display the misoperation of operation adjustment and its troubleshooting measures. The laser photoelectric system is adopted. The laser photoelectric system has the functions of accurate alignment, high sensitivity and simple adjustment, which can effectively ensure the reliable and safe operation of the equipment. The drafting device adopts four roller double short rubber ring drafting form and skfpk1500-001938 cradle spring compression form. The cleaning system is composed of the upper and lower cleaning devices of the drafting part, the blowing device of the car surface and the air suction device behind and above the car, which has a good cleaning and cooling effect. The suspended fully enclosed flyer makes the air flow of the flyer rotating at high speed have no significant effect on the roving itself, and the spun roving has few defects. Safety devices such as automatic alarm for commissioning failure, automatic alarm for lubrication failure, automatic shutdown of two-way photoelectric protection in front of the machine, alarm for opening of each door in the front of the car, alarm for failure of each motor and fan are installed, which are conducive to preventing the occurrence of faults, finding out the causes of faults in time and accurately, and eliminating faults in time, so as to ensure the normal and reliable operation of the machine

2 selection of spinning varieties and raw materials and sliver quality

2.1 spinning varieties

cj 14.5 tex: T/C 55/45 16.8 tex

2.2 selection and feeding of raw materials and the quality of cooked sliver

cj 145 tex and T/C 55/45 16.8 tex cotton parts are shown in Table 1, and T/C 55/45 16.8 tex polyester parts are shown in Table 2

2.3 quality of feeding cooked strips

the quality of feeding cooked strips (doubling is used at the end of the test where the air force is very different) is as follows:

t/C55/45 16.8tex: quantitative 18.09g/5m; The unevenness of Saab's sliver is 13.2%; Stem cv%3.11; Weight unevenness 0.91%.

cj 14.5tex: quantitative 17.45g/5m; The unevenness of Saab's sliver is 12.9%; Stem cv%2.93; Weight unevenness 0.81%.

3 roving process configuration

3.1 configuration analysis of process parameters

3.1.1 roller pressurization

pk-1500 spring cradle pressurization is adopted. There are three levels of pressure for the front, middle and rear of this kind of cradle. The pressure of each level is heavy and the pressurization is stable and reliable. When spinning pure cotton, the medium pressure can meet the process requirements, and the cotton polyester blend, polyester viscose blend, chemical fiber pure spinning, etc. can be appropriately increased (depending on the factors such as the drafting multiple of the rear area and the roller spacing of the rear area).

3.1.2 the original jaw spacing

according to the roving quantity and leaf spring pressure, the original jaw spacing can be smaller on the premise of ensuring that the drafting is normal and does not produce hard heads. It should be determined through trial

3.1.3 roller spacing in the main drafting area

under the condition of ensuring sufficient pressure, in order to minimize the floating range of shorter fibers and improve the roving evenness level, the apron jaw should be moved forward as far as possible to make it close to the characteristics of the second roller grip, so the roller spacing in the main drafting area is too small to meet this requirement. In polyester viscose blended spinning, due to the good length uniformity of polyester fiber and viscose fiber, the roller spacing in the main drafting area can also be appropriately enlarged. In chemical fiber pure spinning, the factor of fiber length integrity should also be considered

3.1.4 drafting multiple and roller spacing in the back area

drafting in the back area is mainly to make the sliver slightly tensioned, straighten the fiber, and make the whisker with a certain degree of tightness enter the main drafting area, which is conducive to improving roving evenness. The drafting ratio and the roller spacing in the back area have obvious effects on the roving evenness, which should be configured reasonably in combination with the pressure. Generally, it is beneficial to improve the evenness of roving sliver if the drafting ratio in the back area is small and the roller spacing in the back area is large

3.1.5 top roller position

in order to reduce the weak twist area of the yarn, reduce roving breakage, and improve the smoothness of the yarn, the center of the front top roller can be moved forward appropriately (the center of the third top roller should be moved backward accordingly)

3.1.6 roving ration

roving ration should not be too heavy to avoid layering of whiskers clamped between aprons due to excessive ration, which will worsen roving evenness

3.1.7 total drafting multiple

the total drafting design capacity is 4.7 ~ 12.8 times, but because the whiskers cause additional unevenness in the drafting process, the fiber shift deviation increases with the increase of drafting multiple, so the total drafting multiple should not be too large in actual production. For medium and fine count varieties, the total drafting ratio is generally controlled at 6.5 ~ 8.5 times, and should not exceed 9.5 times, so as to improve the roving evenness and evenness.

3.1.8 roving elongation

should be controlled too small, so as to reduce accidental drafting and avoid evenness deterioration. The control standard should be reasonably determined according to different varieties

3.2 optimization of roving machine process parameters

3.2.1 test conditions

t/C55/4516.8tex: roving ration 4.90g/10m; The total draft ratio is 7.55 times; Twist 3.07 twist/10cm; Ingot speed 912r/min; Winding density 3.67 layers/cm.

cjl4.5tex: roving ration 4.94g/10m; The total draft ratio is 7.06 times; Twist 4.79 twist/10cm; Ingot speed 912r/min; The winding density is 4.09 layers/cm.

3.2.2 before the tensile testing machine is powered on, the dust and other impurities in the electrical box should be cleaned and the following orthogonal experiments should be carried out:

(1) four factor and three-level orthogonal tests should be carried out on the factors that affect the evenness of roving: the drafting multiple of the back area, the spacing of the back area, the spacing of the main drafting area and the pressure. The test scheme is shown in Table 3 ~ Table 4

(2) after test and analysis, the optimal process parameter configuration is shown in Table 5

4 main technical quality index test of roving

(1) under the condition of relatively stable sliver quality, using the same drawing frame to supply slivers, roving frame and spinning frame to fix the spindle number, the tracking test of CJ 14.5 tex roving big yarn, medium yarn and small yarn is carried out. The test results are shown in Table 6

from the values in Table 4, there is no significant difference in the spinning quality of large yarn, medium yarn and small yarn

(3) roving elongation test. Because the roving machine without iron gun controls the roving tension through the microcomputer system to achieve the effect of constant tension spinning, and adopts the front low and rear high spindle cap to realize equal yarn guide angle spinning, so as to reduce the tension difference between the front and rear rows of roving. In the process of production and operation, aiming at the characteristic of roving frame without iron gun, the roving elongation was mainly tested. In order to facilitate comparative analysis, three kinds of packages of large yarn, medium yarn and small yarn with fixed spindles at the front and rear rows are tested respectively during the test of elongation, and the test cycle is twice a week. See Table 8 for test results

according to the elongation test results in Table 8, the roving elongation test values of CJ 14.5 tex and T/C55/45 16.8 tex are ideal, and the elongation difference between the front and rear rows and the big and small yarns can also be guaranteed to be within the control range. From the analysis of the roving and spinning quality data measured in Table 4, it shows that the roving tension is relatively stable under different winding conditions

(4) see Table 7 for the number of broken ends in 100 roving spindles

(5) comparison of spinning quality between FA425 and FA421 roving frames. Under the same test conditions of drawing and spinning, the comparison of the spinning quality of FA425 and FA421 roving frames is shown in Table 8 (the variety is CJ 14.5tex, and the spindle speed is 800r/min

(6) not for example, the tolerance of line size is partial to the comparison of roving quality under the same spindle speed. The maximum technological spindle speed of FA425 roving frame is 1400 R/min, which is a high-yield roving frame. During normal operation, according to the characteristics of CJ 14.5 tex, the spindle speed is set to 900 R/min ~ 1100 R/min. In order to understand the spinning quality of this type of roving frame under different spindle speeds, CJ 14.5 tex varieties were tested in the range of spindle speeds from 800r/min to 1200 R/min. the test results are shown in Table 9

from the data measured in Table 9, with the increase of spindle speed, the roving evenness has no obvious deterioration trend, and the breaking at 100 spindles has not increased significantly

5 application effect of iron gun free roving frame

(1) from the CV% of roving evenness, the roving evenness of FA425 roving frame can be stabilized at the 25% level of Uster bulletin, and sometimes it can reach the 5% level

(2) from the measured roving elongation value, because the roving machine adopts the constant tension spinning control system, if adjusted properly, the difference between the size of the yarn and the elongation of the front and rear rows can be controlled within 0.5%. From the two tested varieties cjl4.5tex and T/C55/4516.8tex, the elongation difference between yarn and yarn cjl4.5tex is less than 0.15% on average, and T/C55/4516.8tex is less than 0.19% on average; The average elongation difference between the front and rear rows cjl4.5tex is less than 0.11%, and T/C55/4516.8tex is less than 0.14%, indicating that the change of roving tension is relatively constant during a doffing process. According to daily test data, cjl4.5tex roving elongation can generally be controlled within 2.5%, and T/C55/4516.8tex can be controlled within 1.5%, which will not cause quality fluctuations due to improper roving tension

(3) from the perspective of spinning quality, when the speed is increased, the quality does not deteriorate significantly, and the spinning speed adaptability of non iron gun roving frame is good

(4) under the condition of high speed, the spinning quality is stable, there are few broken ends, and the shift production can reach more than 10000 meters

(5) using the roving machine without iron gun, the process adjustment is simple and rapid, especially the adjustment of tension and spindle speed does not affect the normal production and operation. The shift workers can adjust at any time according to the actual operation to make the production more normal due to the huge total amount of packaging, various types and rapid growth of China's express industry

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