Investigation allowing for means of better processing long fine Australian cotton and further

improving ginning efficiency was accomplished. Research was conducted in New South

Wales, Australia. Research trials were conducted using Australian cotton of 30.9 mm and

31.8 mm together with a micronaire value of 3.85. Typical production rates were used

during the research and ranged between 3 200 and 3 800 kg mass lint output per hour.

The feed and discharge of seed cotton was thoroughly investigated. Results show that the

gin stand motor load continually fluctuates as a result of a constantly varying mass input of

seed cotton. Further to this, the distribution of seed cotton presented to the gin stand is in a

non uniform lateral manner. It is probable that the non uniform vertical feed of seed cotton

is further increasing nep and seed coat nep. The cause of the uneven lateral feed of seed

cotton to the gin stand lies within the distributor conveyor design. The conveyor distributor

feeds at rates that allow for a constant feed of seed cotton to three or four gin stands. As a

result of the high speed required to transport seed cotton, the drop zone of seed cotton to

each hopper above the gin stand pre-cleaner is over shot. The trailing edge of the hopper is

also incomplete of seed cotton. The trailing edge incompletion of seed cotton is occurring as

a result of the conveyor distributor auger producing a nip point and dragging the seed cotton

back out of the hopper. The blade of the auger together with the housing of the auger “bite”

the seed cotton and pull the seed cotton back out of the hopper. Methods of overcoming the

problem were trialed. The trials involved methods of redirecting the seed cotton once the

seed cotton was on the gin stand apron. Conveyor distributor modifications were trialed and

involved increasing the seed cotton delivery in the affected areas, in turn, allowing for

greater uniformity.

Fuzzy seed output distribution from the gin stand breast was found to be greatly uneven.

The side of the gin stand most significantly affected was the side seed cotton was delivered

from by the conveyor distributor. This side expels up to four times more fuzzy seed than

other areas of expulsion across the gin stand. The reason that the expulsion of fuzzy seed

occurs at such significant levels can be attributed to the seed roll density. The roll box of the

gin stand is unevenly loaded with incoming seed cotton. The uneven loading of seed cotton

creates areas within the roll box that experience a reduction in density. This reduction in

density creates a movement of fuzzy seed from high density areas to the lower density

neighboring areas. Therefore, high levels of fuzzy seed expulsion occur in areas of lesser

density. The output of fuzzy seed approximates to the inverse of the input of seed cotton.