Abstract: A sluice valve arrangement is adapted to make an air-tight partition or communication between a vacuum treatment chamber and the atmosphere or a pre-chamber. This arrangement includes a valve seat member comprising a cylindrical or spherical member having therein an opening, a pair of guide rails attached to the inner circumference of the seat member, a valve member movably supported on the guide rails, and means for air-tight engagement of the valve member and the valve seat portion of the seat member. The valve member has a curvature equal to that of the cylindrical or spherical member, and the engagement means comprises a plurality of bellows expandable by a compressed gas or air.

Abstract: A vacuum furnace for heat treatment comprises a heating furnace proper, pre-exhaust chambers, one adapted to feed a workpiece into the furnace proper therefrom and the other adapted to discharge the workpiece out of the oven proper thereinto, vacuum valves for partitioning between the oven proper and the respective pre-exhaust chambers, and a line assembly for deliver of the workpiece from the feed chamber into the discharge chamber through the furnace proper. A heating chamber forming part of the furnace proper is positioned on the upper part above the deliver line assembly, and an externally operable elevating means is disposed in the furnace proper. The work pieces carried by the delivery line assembly, and lifted to the heating chamber where it is heated.

Abstract: A process for producing a metal vacuum bottle composed of internal and external shells made of metal, said process comprising the steps of brazing the seamed portion formed between said two shells through a vacuum heating treatment for an assembly of the vacuum bottle accommodating a getter to be sealed therewithin, and of enhancing the vacuum degree between said shell by maintaining the temperature of activating the getter for a certain period of time.