Trouble shooting guide for vacuum furnace

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After vacuumizing, the vacuum furnace is filled with hydrogen gas to control the pressure in the furnace and the sintering state of atmosphere. It is pollution-free to the environment and does not need to carry out three wastes treatment. What problems do you encounter when using the device?

Causes of vacuum furnace pump stuck during operation:
(1) Sundry oil is pumped into the oil
(2) Working under high pressure for a long time makes the pump overheat
(3) Expansion of parts, too small clearance

Exclusion method:
(1) Pump removal and repair
(2) The pump should not work under high pressure for a long time
(3) Strengthen the cooling of the pump

Causes of fuel injection:
(1) Inlet pressure too high
(2) Too much oil exceeds the oil cup

Exclusion method:
(1) Reduce the pressure at the air inlet
(2) Drain excess oil

Causes of high oil temperature:
(1) Debris suction pump
(2) Suction gas temperature too high
(3) Insufficient cooling water
Exclusion method:
(1) Take out the sundries
(2) Cooling device on air inlet pipe
(3) Increase cooling water flow

Cause of high temperature not reaching rated value:
(1) Necrosis of heat shield
(2) Aging of electric heating elements
Exclusion method:
(1) Repair or replace the heat shield
(2) Replace the electric heating element

Causes of temperature control failure:
(1) Thermocouple wire disconnection or contamination
(2) Temperature control instrument failure
(3) Reverse connection or short circuit of thermocouple compensation lead
Reason for exclusion:
(1) Replace thermocouple
(2) Repair according to the instrument manual
(3) Reconnection or exclusion

Causes for the surface of oil quenched parts not bright:
(1) Low furnace vacuum
(2) Quenching cooling oil degassing is not complete
(3) Oil inlet temperature too high
Reason for exclusion:
(1) Improve furnace vacuum
(2) Quench cooling oil degassing
(3) Oil in according to the specified temperature

Causes for the surface of air quenched parts not bright:
(1) Low furnace vacuum
(2) Insufficient purity of protective gas
(3) The inflation pipeline is not pre aspirated
Exclusion method:
(1) Improve furnace vacuum
(2) Improve the purity of shielding gas
(3) The gas filling pipeline should be pre pumped before each boiler opening

Causes of volatilization of alloy elements on the surface of parts:
(1) High vacuum
Exclusion method:
(1) Control the vacuum degree of furnace according to different parts and materials