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Precautions for operation of sheet pressure furnace

 

 

1. The interval between quenching and tempering shall not be more than 4h, the shape of complex parts and high alloy steel parts shall not be more than 1h, and the large parts and high alloy steel parts shall be tempered in the tempering furnace immediately after quenching and heated into the furnace, otherwise they will crack.

 

 

2. The tempered parts are not allowed to enter the workpiece in the cold furnace, and the high temperature tempering of complex shaped parts can be stepped up.

 

 

 

3. Low temperature tempering is not suitable for steel parts requiring cryogenic treatment before cryogenic treatment, so as to avoid thermal stabilization of retained austenite.

 

 

4. The workpieces need to be tempered for many times. After each tempering, they should be cooled to room temperature, and then tempered for the next time to promote the transformation of retained austenite.

 

 

5. Long and thin members shall be suspended vertically for tempering to prevent warpage and deformation. During pressure tempering of sheet metal, pressure shall be applied regularly.

 

 

6. Add more than 2% NaOH to the bath for tempering every week to reduce the oxidation of the bath.

 

 

7. The operator should always check the accuracy of tempering furnace temperature

 

 

8. The tempering of workpieces is better to be installed on the material basket or special fixture to ensure that the furnace gas circulation and furnace temperature are even. 9. The workpieces in and out of the furnace shall be handled with care, and shall not be thrown or placed around, so as to prevent the furnace or electric heating elements from being damaged.