1968 Volume 24 Issue 4 Pages 196-203
In order to get high production on a cotton card, it is necessary to increase the amount of a lap fed to the card. It is to be remembered, however, that the number of neps formed in a sliver produced is strikingly increased when the amount of the lap fed is only increased without changing the speed of other parts of the card.
It can be expected that the number of neps in the sliver produced may not be so much increased when the speed of such parts as the cylinder, taker-in roller, doffer and other parts of the card are increased proportionately with increase of the amount of the lap fed, because the density of fibers on the combing surfaces of those parts are almost the same regardless of the amount of the lap fed.
The experiments were carried out under the following conditions. The speed of the cylinder is increased from 170 to 250 or 340 rpm, and the speed of each part revolved is varied in proportion to that of the cylinder and so the amount of lap fed by the feed roller is changed from the same to twice or thrice as much as the conventional amount.
Then, the number and the size of neps in the sliver and the yield rate of the sliver produced under the above conditions are measured and the results obtained are as follows:
(1) Even when the speed of each part on the card is increased up to twice the times of that on the conventional card in proportion to the speed of cylinder, changes in the number and the size of neps in the produced sliver are scarcely found.
(2) It is found that the yield rate of the sliver produced under the condition mentioned in (1)-the speed of each part of the card is doubled- shows a slight decrease (about 0.5%) and the rate of its decrease is less than that was expected.
