Abstract
As usual the opening grade of cotton is tested by handling method, but it is very difficult to compare the results depending upon different method used.
In order to decide the degree of opening action of machinery, the terminal velocity and coefficient of air resistance of cotton tuft at free falling were measured. The coefficient of air resistance is usually better than the terminal velocity to indicate the opening efficiency of blowroom machinery.
Formula of the terminal velocity um, and coefficient of air resistance C are following:
where w′: apparent weight of cotton tuft,
l: length of cotton tuft,
pρf: density of air.
The smaller the terminal velocity or coefficient of air resistance is the more the cotton tuft is opened. Combination of the 1st Hopper Bale Breaker, Lattice Feeder, Exhaust Opener and Finisher Scutcher are more effective for opening action. 1st Crighton Opener with Deliverly Lattice and 2nd Crighton Opener are not so effective.
