It has been scientifically proven and accepted that cyclones are very effective in keeping particulate from cotton gins where it belongs – out of the air and into the trash pile. When properly designed, installed and maintained, these simple, reliable and efficient workhorses meet all current state and federal cotton gin air pollution compliance regulations that I am aware of. However, even a good horse can be ridden into the ground, and the same is true of cyclones. Because cyclones are so reliable, they can be ignored for long periods of time and still keep on doing their job, but once in a while even cyclones need a little TLC.
Now that most gins should be finished or on the downhill side of the 2011 ginning season, this might be a good time to talk about cyclone repair and maintenance to get ready for the next season. There is a publication called Using Cyclones Effectively at Cotton Gins that covers most current cyclone usage and maintenance, and I would be glad to send a copy if requested.
One of the first things to consider is airflow to the cyclones. Any leaks in piping need to be repaired as they affect air flow to the cyclone and may affect particulate collection efficiency. Leaks in cyclone bodies or cones caused by wear also affect air flow and should be fixed by new replacement of the body or cone. The new body or cone should be of rolled construction and smooth inside with all welds or seams ground smooth so there are no obstructions.
If a temporary repair is done by welding on a metal patch, the inside of the patched area must be filled and ground
smooth. Even a protruding seam weld or cavity anywhere on the inside of a cyclone will decrease its efficiency.
There are other things to consider when replacing worn out cyclone parts or entire cyclones with new ones. You may not want to simply replace one of these parts. But go ahead and measure the air flow to determine if the cyclone is properly seized for the air flow it now receives for best collection efficiency.
Air flow measurement is relatively simple, and any “Certified Ginner” graduate from the three gin schools sponsored by the National Cotton Ginners Association has been trained to make the measurements. If help is needed to make the air measurements, most state ginning associations can recommend experienced contractors to provide the service.
If replacing older 1D3D cyclones (where D is the cyclone diameter), it would be a good time to use the newer 2D2D style inlets instead of either of the older design 1D3D dust or trash inlets. Using the newer inlet will also necessitate replacing the transition from the round pipe to the inlet. But it will decrease the likelihood of chocking at the inlet and help maintain maximum cyclone particulate collection efficiency regardless of cyclone loading.
Another consideration on older 1D3D trash cyclones when replacing the cone is to use the D/3 trash outlet rather than the older D/4 outlet (in no case should the outlet be smaller than 12 inches in diameter). The larger trash outlet will decrease incidence of choking at the outlet caused by large trash and will not decrease the cyclone’s collection efficiency.
Other things to consider when replacing cones of either 2D2D or 1D3D cyclones are 1) for heavily loaded trash cyclones installing two piece cones so that the lower portion, which is most prone to wear, can be replaced without replacing the whole cone or 2) putting expansion chambers on the bottom3Ž4D length of the cone to help stabilize the cyclone vortex and maintain the highest particulate collection efficiency.
– Ed Hughs is Director of the Southwest Ginning Research Laboratory in Mesilla Park, N.M. Contact him at (575) 526-6381 or firstname.lastname@example.org.