A Virginia-based manufacturer of high-quality plumbing tube commissioned a SECO/WARWICK solution heat-treat furnace to expand its capabilities to include aluminum extrusions. This is the first installation of new aluminum-processing equipment at the plant. Tubing extrusions and other shapes up to 26 feet long are loaded horizontally at floor level into a load carriage. The carriage containing the load is then pulled by a hoist from one end until it is vertical next to the furnace. The carriage is then secured to the supporting structure, allowing the hoist to lower the load down and out of the carriage. The load is lowered into a powered rotating carousel, which contains two submerged drywells that extend below the floor into the water-filled pit. The load is then supported by the carousel, allowing the hoist to be released. The carousel rotates until the load is in position directly below the furnace. The furnace door opens, and a second hoist retrieves the load, pulling it up into the furnace chamber for heating.
After heating, the furnace door opens and the load is lowered into one of two open positions in the carousel, allowing the load to quickly cool in the water-filled pit below. The vertical orientation of the work being heat treated is what differentiates this unit from others. The design allows the company to maintain an efficient, semi-continuous process with little downtime between batches by staging loads in the drywells.
The major benefit of this design is that it allows the tube manufacturer to drop extrusions into the quench within 10 seconds after heat treating and soak. The rapid quench is done quickly to “lock in” the hardening elements of the alloy. By heating the work up to a temperature slightly below the melting point, the hardening elements will disperse throughout the cross section of the work.