What needs to be prepared for the temperature uniformity test of the vacuum brazing furnace
1. Test the measuring thermocouple and temperature control thermocouple according to the relevant regulations in GB/J351-1996, and the furnace temperature uniformity can be measured only after the test is qualified. Remove the cover plate of the temperature measuring hole from the furnace body, put 9 qualified thermocouples on sealing gaskets and rubber gaskets in sequence, introduce them into the furnace cavity from the flange holes, and fix them in the position according to the standard. On the furnace door support frame, the size of the support frame is the effective heating size.
2. Carefully move the support frame into the furnace cavity, place it on the furnace bed, and adjust its position so that it coincides with the effective heating space. Fix the thermocouple hole of the temperature measuring flange, put the sealing gasket in sequence, apply vacuum grease on the rubber gasket, tighten the compression bolts, and install the flange.
3. Manually start the vacuum mechanical pump and the vacuum roots pump to pump the vacuum according to the operating rules, until the working vacuum reaches 2Pa, stop for 30 minutes, observe the vacuum gauge reading, and see if the pressure rise rate is within the normal 0.5Pa/h. If it is normal, continue to measure the furnace temperature uniformity. If it is abnormal, re-adjust and tighten the bolts and re-measure the pressure rise rate. Until it is normal, the furnace temperature uniformity measurement can be continued.