When it comes to integrating material handling with process heating applications, LEWCO is second to none. Recently, LEWCO used its expertise to design and manufacture two continuous process heating cells equipped with ovens, conveyors, and cooling zones. The 800°F ovens are used to cure polyethylene foam contained in aluminum molds.
LEWCO engineers developed each oven with (2) independent mesh-belt conveyors passing through the same workspace. Operators can adjust the speed of the conveyor separately to yield proper dwell times. The conveyor speed is adjustable from 1.5-2.5 feet per minute through the use of a variable frequency drive. These ovens are designed to meet NFPA 86, Class B standards and include a top mounted heater-box with 1,000,000 BTU heat input. A 6,000 CFM high-efficiency circulation blower delivers dual airflow to the workspace.
Parts are manually loaded into the oven by operators. Once the molds pass through the oven they are automatically transferred to a 180 degree curve belt conveyor. The conveyor is equipped with a special white silicon cover that is suitable to handle temperatures up to 450°F. From there the molds are transitioned to two mesh belt cooling conveyors that transfer the mold back to the load end of the oven. There the finished product is removed and the molds are refilled with foam to repeat the process.
LEWCO’s control engineers adapted standard designs to accommodate special component requirements from the customer. This included special temperature controls and variable speed drive controls they currently use throughout their plant.
Before shipment, the customer visited LEWCO to test and inspect one of the conveyor ovens. Based on the run-off test, the customer stated they will be able to increase their production by 15%. The results were so impressive an order was placed for two more heating cells within two weeks of delivery.