Customized high vacuum brazing electric furnace with abnormal vacuum degree

10-13-2025       Author: KJ technology

The common reasons and solutions for abnormal vacuum degree in customized high vacuum brazing electric furnaces are as follows:

1. Vacuum system malfunction

Vacuum pump issue

Possible reasons: low pumping efficiency of the vacuum pump, oil contamination, wear of the shaft seal, etc.

Solution: Inspect or replace the vacuum pump, clean oil contamination, and replace the shaft seal.

Case: A certain device experienced a decrease in pumping efficiency due to contamination of the vacuum pump oil. After replacing the oil, the vacuum degree returned to normal.

Vacuum pipeline leakage

Possible reasons: Poor valve sealing, loose pipeline connections, etc.

Solution: Conduct leak detection on the vacuum system, identify the leakage point and repair it, such as replacing the valve sealing ring and tightening the pipeline connection.

Case: A certain device leaked due to the aging of the valve sealing ring. After replacing the sealing ring, the vacuum degree reached the standard.

Vacuum gauge malfunction

Possible cause: Damage to the resistance gauge and ionization gauge.

Solution: Replace the gauge of the vacuum gauge.

Case: A certain device showed abnormal display due to damage to the vacuum gauge tube. After replacement, the vacuum degree measurement was accurate.

2. Sealing problem of furnace body

Seal aging or damage

Possible reasons: Aging or damage to furnace door seals, electrode seals, etc.

Solution: Check and replace aging or damaged seals to ensure proper installation.

Case: A certain device experienced a decrease in vacuum degree due to aging of the furnace door sealing ring. After replacing the sealing ring, the vacuum degree increased.

Leakage of furnace body weld seam

Possible reasons: Cracking of furnace body welds or poor welding quality.

Solution: Conduct leak detection on the welds of the furnace body, and if necessary, perform repair welding or replace the furnace body.

Case: A certain equipment leaked due to cracking of the furnace body weld seam, and the vacuum degree returned to normal after welding repair.

3. Material deflation issue

Release of gas from materials inside the furnace

Possible reasons: Gas is released after adsorption on the inner wall of the furnace shell, insulation materials, and surface of the heat exchanger.

Solution: Regularly clean the furnace body to maintain cleanliness inside the furnace; Apply an anti-oxidation coating on the surface of the heating element; Dry the product.

Case: A certain device experienced a decrease in vacuum due to air release from the surface of the heat exchanger inside the furnace. After cleaning the heat exchanger, the vacuum level increased.

Workpiece deflation

Possible reasons: Air release from the material of the product to be brazed, air release from the threaded hole during assembly, etc.

Solution: Dry the product to ensure it is dry; Improve assembly process and reduce gas release.

Case: A certain device deflated due to the product not being dried, and the vacuum degree returned to normal after drying.

4. Other issues

Cooling system issues

Possible reasons: insufficient cooling water supply, blockage of cooling system, etc.

Solution: Check if the cooling water pipeline is unobstructed to ensure sufficient cooling water supply; Clean up blockages.

Case: A certain device experienced a decrease in vacuum due to blockage of cooling water, but after cleaning, the vacuum returned to normal.

Control system issues

Possible reasons: incorrect controller settings, sensor malfunctions, etc.

Solution: Check the settings of the controller to ensure that the parameter settings are correct; Check the working condition of the sensor and replace the faulty sensor if necessary.

Case: A device experienced abnormal vacuum due to incorrect controller settings. After adjusting the parameters, the vacuum returned to normal.