Abstract: In an apparatus for treating workpieces by means of the igniting of a gaseous mixture in a work chamber for receiving the workpiece, it is proposed that the work chamber and optionally the supply duct for the gaseous mixture, as well as a mixing block for preparing the gaseous mixture which precedes the supply duct, are provided at least in part with a lining of ceramic material in the form of aluminum oxide or zirconium dioxide, in order to intercept the corrosive action exerted by the ignition of the combustion gas-oxygen mixture upon these parts of the apparatus.

Abstract: After a combustion chamber is filled with a combustion mixture of gases, channels extending upward from the valves for admitting the gas components of the mixture to a gas inlet bore are flooded with a quantity of water injected through an additional valve by a hydraulically driven piston. After the hydraulic pressure behind the piston is turned off, the water chamber in front of the piston is refilled by the inflow of water at water line pressure, which is not sufficiently high enough in pressure to reopen the water outlet valve until the piston is again driven.