Method of cooling a quenching bath of melted salt

A method of cooling a treatment bath of melted salt into which heat is being introduced by the work or substance which is being treated therein, as when hot workpieces are quenched, for example, the salt bath cooling method comprising the steps of:

• using a primary cooling medium a liquid whose boiling point lies substantially below the operating temperature of the salt bath;
• heating said liquid primary cooling medium to a state of partial evaporation, so as to create a mixture of liquid and vapor;
• introducing said liquid and vapor mixture into the salt bath, in direct contact therewith, thereby
• evaporating the remaining liquid portion of the cooling medium through direct heat transfer from the melted salt to the cooling medium, with the previously evaporated portion of said cooling medium acting as an atomizing agent on the liquid portion of the cooling medium, thus controlling its expansion during evaporation;
• and
• agitating the treatment bath by utilizing the expansion forces acting on the completely evaporating cooling medium to entrain a portion of the melted salt in a circulatory flow.