The influence of licker-in speed on the fiber length index after carding was studied. The fiber length index of the processed sliver, cover plate flower, lint roll lint, and large leak bottom drop were tested with the USTERAFIS single fiber tester. The results show that the carding process will increase fiber damage and increase the total amount of short fluff after carding. The order of the fiber short fluff rate in the sliver and the falling parts of the card after the carding order is the bottom leakage, licker-in, and cover flower. , Sliver. It is considered that the reduction of short lint in the sliver is the most favorable when the licker-in speed is 800 r / min, and the short lint that is removed from the lint roll is the most; most.
Experimental part
1.1 Raw materials
AFIS test results of Xinjiang cotton used: average fiber weight 25.7mm, short weight rate (<16mm) 10.6%, longest 25% fiber weight average length 30.3mm; average number of fibers 21.7mm, number of short fibers (<16ram) 25.9%, the longest 5.0% fiber number average length 34.3mm. The total number of neps was 225 grains / g, and the average size of neps was 675 μm; the average size of neps with seeds was 4 / g, and the average size of neps with seeds was 1136 μm. The total number of impurities is 173 grains / g, the dust is 142 grains / g, and the grains are 31 grains / g. The foreign matter rate is 0.69%.
1.2 Test process
A002 cotton catcher → A006B cotton blender → A034 multi-roller cotton opener → A036 porcupine cotton opener → A092 double cotton box feeder → A076A single beater coiler → A186F .
1.3 Test conditions
The cotton rolls used in the tests were processed by the same series of cotton clearers at the same time. The cotton roll weight was 425g / m. A186F carding machine used in the test (has been modified and equivalent to the FA series carding machine). The cylinder speed is 360r / min; the doffer speed is 30r / min; , 1200r / min, 1400r / min; small leak bottom inlet spacing 6mm, fourth point spacing 1mm, outlet spacing 1mm, dust removal blade spacing 0.36mm; 4 rear fixed cover plates, their spacing from bottom to top It is 0.89mm, 0.76mm, 0.64mm, 0.51mm, the tooth density is 90 teeth / (25.4mm) 2, and the sliver weight is 25g / 5m.
1.4 Test method
Before testing each scheme, first lay a plastic film on the entire space under the belly of the car, and use a vertical baffle at the junction of the bottom of the large leak and the bottom of the small leak to separate the lint roller and the large leak bottom from Collected in categories. Clean the cover knife and the top of the front cover to collect the cover flowers accurately. After each test program spins two cotton rolls, the machine stops and collects the cover flowers, licker-in rolls and large leaks.
In order to ensure the high accuracy of the test results, each test protocol randomly took 30 sub-samples of sliver, cover plate flower, lint roller lint and large leak bottom drop, each sub-sample was about 0.5g, and subjected to AFIS test.
2.1 Change of fiber length index after carding
Short fiber rate: The fiber short fiber rate in the cover flower is between 47.7% and 49.5%, with an average value of 48.1%; the fiber short fiber rate in the lint roll noil is between 48.3% and 53.1%, and the average value is 50.2%. ; The rate of fiber fluff in the bottom of the large leak is between 76.9% and 80.9%, with an average of 79.7%. This shows that the cover, licker-in, and large leak bottom all have the function of excluding short fluff; and the fiber lint rate in the bottom of the large leak is the largest, indicating that the large leak bottom has the strongest ability to remove short fluff, followed by the licker-roll, Cover. Compared with the above three falling objects, the fiber fluff rate in the sliver is the smallest. Therefore, the order of the fiber lint rate in the sliver and the falling parts of the card after the carding is large leakage bottom drop, licker-in, cotton cover, and sliver, and the regularity is very obvious.
Average length of roots: When the speed of the licker-in rollers is 800r / min and 1000r / min, the average length of the number of roots in each part of the comb after carding is sorted as cover plate flowers, licker-in cotton, and large-leaf bottom-drops; At 1200r / min and 1400r / min, the average length of the number of roots is sorted as licker-in, cotton, cover, and large-leaf bottom drop. Compared with the three types of drop, the average length of the fiber number in the sliver is the longest. . In general, the order of the average length of the fiber roots in the sliver and the falling parts of the card after carding is opposite to the order of the number of fluffs, and the order is the sliver, the cover flower, the lint roll lint, and the large leak bottom drop.
The average length of the longest 25% fiber weight and the average length of the longest 5% fiber number: When the licker-in roller speed is 800r / min, the average length of the longest 25% fiber weight and the longest 5% fiber root in each part of the card after carding The average size of the two indicators is sorted by cover flower, licker-in, lint-dropping, and bottom-leakage; when the licker-in speed is 1000r / min, 1200r / min, and 1400r / min, the objects in each part are combed. The average length of the longest 25% fiber weight and the longest 5% fiber root number are sorted in the order of licker-in, nozzle cover, and large-leaf bottom drop. Compared with these drops, sliver Both the longest 25% fiber weight average length and the longest 5% fiber root number average length are the longest. In general, the two indexes of the longest 25% fiber weight average length and the longest 5% fiber root average length after carding and sliver falling in each part are sliver, licker-in, cotton cover, Large leaking bottoms (when the licker-in speed is 800r / min, the longest 25% fiber weight average length and the longest 5% fiber root average length in the licker-in cotton and cover flowers are sorted slightly. no change).
2.2 Impact of licker-in speed on fiber length index
2.2.1 Effect on fiber length index in sliver
According to Table 1, when the licker-in speed is 800r / min, the average length of the fiber number in the sliver, the average length of the longest 25% fiber weight, and the average length of the longest 5% fiber number are the longest, and the lint rate The smallest. This shows that the lint roll speed of 800r / min is most conducive to the reduction of fluff in the sliver.
2.2.2 Effect on fiber length index in cover flower
According to Table 1, it can be seen that when the licker-in roller speed is 1400r / min, the average length of the fiber number in the cover flower, the average length of the longest 25% fiber weight, and the average length of the longest 5% fiber number are the shortest, and the lint rate maximum. This shows that when the licker-in speed is 1400r / min, the short fluffs excluded from the cover flower are the most.
2.2.3 Effect on fiber length index in lint noil
According to Table 1, it can be seen that when the licker-in speed is 800 r / min, the average length of the fibers in the licker-in waste is the shortest, and the average length of the longest 25% fiber weight and the longest 5% of the fiber is the shortest. maximum. It shows that the lint removed from the licker-in is no more than the lint-roller speed of 800r / min.
2.2.4 Effect on fiber length index in bottom of large leak
According to the above discussion, it can be seen that when the licker-in roller speed is 1000 r / min, the average length of the fiber number in the bottom of the large leak, the average length of the longest 25% fiber weight, the shortest average length of the longest 5% fiber number, and the minimum fiber length Number short fluff rate is the largest. This shows that when the licker-in speed is 1000 r / min, the lint removed by the licker-in is the most.
in conclusion
(1) Carding process will increase the fiber damage and increase the total amount of short fluff after carding.
(2) The cover, licker-in, and large leak bottom all have the function of excluding short fluff; and the short fluff rate in the large leak bottom drop is the largest, indicating that the large leak bottom has a stronger ability to remove short fluff.
