Inert gas atmospheres

Bell type furnaces

Bell type furnace

In the heat resistant retort tubular heating elements are mounted and fan for uniform heating of hardened steel parts in an inert noble gases helium (He) or argon (Ar) at temperatures up to 700 °C, holding at this temperature and cooling to about 150 °C. Surfaces of tempered steel parts remain clean without the appearance of oxidation or decarburization. Developed gassing system ensures minimal consumption of expensive inert gas. Rapid cooling is carried out venting the outer mantle of retort.

Furnace is used for high-temperature tempering of hardened tools made of hot work tool steels, high speed steels and precision parts made of structural steel when the changes in the composition of the surface are not allowed.

Pit type furnaces

Pit type furnace

Pit type furnace for tempering in the inert gas is suitable only for application of argon (Ar) which is significantly denser than air, and applies a system of controlled gassing of retort from the bottom upwards. Protection of surface components is identical to that of bell furnaces. The difference is in the way of charging the furnace.

Air atmosphere

Pit type furnace

Tempering in the air atmosphere is used in cases where a slight oxidation is not harmful as it is predicted subsequent machining. There are different types of furnaces for tempering in the air atmosphere like bell type, pit type, chamber type.