Q. We have been reviewing the costs of operating for our powder coating line and notice that gas is a big part of it. We have two heated stages in our washer, a dry-off oven, a cure oven and a burn-off oven. Can you give us any advice on ways to cut our gas use?
A. We see these kinds of questions a lot these days. Gas use is related to the size of the equipment, the amount of load processed, the process temperatures and the overall equipment design. The equipment size is not a variable that you can change or control, and the load is based on production needs. The things that you can control are the temperatures and the equipment design. Evaluate the operating temperatures to see if you can reduce them. Perhaps you can change washer chemistry and get the same results at a lower temperature. You may be running the dry-off higher than necessary. You may be able to use a powder that cures at a lower temperature and still provides the needed performance.
Several possible changes to the equipment also should be evaluated. Insulation on the washer tanks and tunnels can be very effective at reducing gas use. Adding an additional layer of insulation on the ovens also can be very cost effective. Also take a look at the entrances and exits of the ovens. A lot of heat loss occurs at the openings, and a properly designed air curtain or an extension of the vestibule can save some loss. Check your exhaust rates from the ovens. If they are too high, you can reduce them and save some gas there. Make sure your equipment is well maintained so that filters are not plugged and burners are firing properly. If you do not have one already, install an interlock to reduce the oven temperatures if the conveyor is stopped for an extended period of time. Load your line densely to get as much output as possible per hour. These are a few simple suggestions. Good luck.