Salt electrode bath is a metal or ceramic bath filled with salt , in which electric heaters are lowered. The part of the bath in which the electric heaters are located is separated from the working part by a partition. The bath is placed in the body and covered with an umbrella at the top. A special immersion electric heater is used to start the bath. Salt baths provide fast and uniform heating of products placed in molten salt. They are used, in particular, for heating for quenching and tempering of tools.
Benefits:
- faster (4-5 times) heating, compared to electric and gas heating furnaces;
- uniform heating of the entire surface of the part;
- uniform temperature field in the entire melt with an accuracy of ± 1 ° C;
- the possibility of partial heating for quenching (for example, only the working part of the drill or the impact part of the chisel);
- when heating parts do not oxidize;
- high operating temperatures:
NaCl - 800 ... 1100 ° C BaCl2 - 962 ... 1300 ° C
Disadvantages:
- quite harmful evaporation of MPC of evaporation of NaCl - 0.04 g / m³ (when heating the salt above 870 °, chlorine begins to release. MPC of evaporation of BaCl2 - 0.004 g / m³
- if water enters the salt, or loading wet parts causes an explosion and release of molten salt over a sufficiently large distance