THERMOFORMING: New Oven Streamlines Preheating

Unit uses both electricity and gas to preheat products.

A new thermoforming oven from Davron Technologies, Chattanooga, Tenn. uses both electricity and gas to preheat products. Called the DTI-1244, Davron says the oven is being deployed by a Tier 1 automotive supplier that forms interior components.

A specialized indexing conveyor oven, the DTI-1244 allowed this undisclosed processor to streamline its preheating process by eliminating steps that required additional handling of the products. Previously, the preheating process required two separate preheating systems (a contact press and a convection oven), along with the associated labor resources required to load both systems.

The DTI-1244 includes a two-tier system that performs both preheating functions simultaneously. The upper tier features a contact press that utilizes two heated platens with a decline conveyor. The upper and lower platens are heated by electric rod elements. The lower tier features a natural gas heated convection oven and a wire mesh conveyor belt. Product is loaded simultaneously on the entrance end of both the upper and lower tiers and is indexed one position into the contact press and the convection oven chamber. Once preheated, both products index one more position, exiting the oven simultaneously. They are then matched together to form a preheated vehicle set ready to be press formed into a single unit.

Both tiers of the DTI-1244 thermoforming oven can operate between 200 and 500 F. The DTI-1244 features PLC control, and all motion functions are controlled by servo for accuracy and speed. The overall dimensions of the indexing conveyor oven’s system are 19-ft wide x 36-ft. long. The interior of the convection oven is made out of 16-gauge aluminized steel backed by six inches of eight-pound density mineral wool insulation. The exterior is constructed of 16-gauge carbon steel backed by a structural steel frame and finished with high- temperature paint. The upper tier utilizes a Teflon-coated conveyor belt, and the lower tier utilizes a wire mesh conveyor belt.

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