outside quenching chamber 11 rollers 16 of transport device 15 serve as the support for metal workpieces 18 arranged in the center of quenching chamber 19 beneath transport device 15 is a duct designated overall as 25 which has an open top duct section 24 duct section 24 widens in its upper region and opens directly beneath rollers 16 in the quenching position shown according to fig1 workpieces 18 are located above the space enclosed by open top duct section 24 open top duct section 24 continues above rollers 16 in the form of a correspondingly shaped frame 34 with laterally closed valves frame 34 is open at the top frame 34 is connected via vertical holders 35 to a hood 32 which encloses frame 34 from the outside and with its lower end extends to rollers 16 of transport device 15 frame 34 can be moved vertically together with hood 32 by means of a lifting apparatus 46 in the position shown in fig1 workpieces 18 have already been moved on the roller conveyor into a stipulated quenching position and are there enclosed by frame 34 which is lowered from above while the roller conveyor is stationary the quenching process can now begin for this purpose quenching liquid is first pumped in the direction of an arrow 26 upward from below through open top duct section 24 so that quenchant 12 floods onto workpieces 18 from below quenchant 12 rises inside frame 34 then emerges laterally outward over.