Immersion of automotive parts in a fluidized bed of foundry sand is used to both strip the castings free from moulding sand and to heat-treat the castings at 500?C.The fluid bed is heated by hot gases from a burner directed first into a serpentine heat exchanger located near one side-wall of the rectangular tank,and then into a distributor consisting of horizontal sparger pipes having maintenance standpipes fixed into their upper surfaces. Immersion of automotive parts in a fluidized bed of foundry sand is used to both strip the castings free from molding sand and to heat-treat the castings at 500 ° C. The fluid bed is heated by hot gases from a burner directed first into a serpentine heat exchanger located near one side-wall of the rectangular tank, and then into a distributor consisting of horizontal sparger pipes having maintenance standpipes fixed into their upper surfaces.