Possible scrapping of vacuum brazing furnace products and Solutions – 4

16. the product is not smooth scrap
17. vacuum brazing furnace power outage emergency method
18. How to stop circulating water in vacuum brazing furnace
19. What should I do if the vacuum furnace leaks

16. Product surface is not smooth and scrapped
1. Phenomena and causes: In the process of high temperature brazing, the product is deformed to a certain extent. After leveling, the plane does not meet the technical requirements, called uneven scrap. At present uneven scrap plate – type products are few.
2. Solutions: The jigs and fixtures need technical improvement;
3. Improve vacuum brazer mounting fixture.

17, vacuum brazing furnace power outage emergency method
1. Phenomenon and reason: Power failure occurs suddenly when the vacuum furnace is brazing normally.
2. Solutions:
1, first close the vacuum furnace mechanical pump Angle valve.
2. Turn on the standby tap water or start the standby diesel engine to supply circulating water.
3. When the temperature in the vacuum brazing furnace is lower than 1120℃, it must be naturally cooled to about 800 ℃ according to the real-time temperature in the furnace (the time shall be determined according to the actual temperature ratio table of the vacuum furnace after power failure, before nitrogen flushing. The nitrogen flow is the same as the pressure.
4. No matter how long the power outage lasts, nitrogen in the furnace must be kept above 0.5Pa and less than 0.5Pa must be timely replaced. Until it cools to 80 degrees.
5, the furnace temperature below 800 degrees, can be directly rinsed nitrogen protection, 6, after the power supply is normal, according to the real-time temperature in the furnace, according to the usual procedures.

18. Emergency method for stopping circulating water
1. Phenomenon and reason: The circulating water supply is suddenly stopped due to the pump and other reasons.

2. Solution: When the alarm goes off after the circulating water stops, you must immediately go to the pump room to find out the reason. When the water cannot be supplied for 3 to 10 minutes, the diesel engine must be turned on or the water main valve switch must be turned on.

19. What should I do if the vacuum furnace leaks
1. During the operation of vacuum brazing furnace, under the dual action of high temperature and pressure difference (pressure inside the furnace interlayer and water pipe, and the furnace body is in the vacuum state), there are defects in the welding place of vacuum brazing furnace shell due to long-term cold and heat due to force reasons, resulting in leakage of vacuum brazing furnace. It is not noticeable at low temperatures and starts to leak at high temperatures. Cause the product to blacken. Product obsolescence. The glass wall of the measuring resistance gauge on vacuum brazing furnace is broken due to the alternating temperature of cold and hot. Product obsolescence.
The problem of micro – water seepage will occur in the micro – hole of vacuum brazing furnace.
The inspection scheme of vacuum brazing furnace is as follows: the water in the vacuum brazing furnace sandwich and water pipe is blown clean with compressed air, and then the vacuum pump is connected to the inlet or outlet of the furnace sandwich and cooling water pipe to vacuum the furnace sandwich and water cooling pipe, so as to detect the leakage of the furnace sandwich and water pipe.

2. Solution: cut off water in vacuum brazing furnace, vent cooling water in the sandwich of vacuum brazing furnace, and flush 10KG of compressed air. The leak can be found with helium mass spectrometer.
3. Check the technical indexes of vacuum brazing furnace to meet the requirements of vacuum performance indexes.