Safe operation procedure of vacuum brazing furnace
1. The electric cabinet delivers electricity, delivers water and ventilates.
2. Open the maintenance pump, press the diffusion pump start switch after 2 minutes, and heat the diffusion pump. Observe whether the current of the diffusion pump is normal and the diffusion pump preheats for about 1-1.5 hours (note: the pump outlet can not be blocked)
3. In the preheating device, the workpiece can be carried out in the furnace. After loading and unloading, the furnace door is locked in place (bear in mind that no other items are left in the furnace except the workpiece)
4. The diffusion pump preheating time, open two mechanical pumps, open the pre-bleed valve in 30 seconds, and exhaust the vacuum furnace. When the vacuum reaches 1-2 kpa, the Cairo pump. When you draw 7-8 pa, close the pre-bleed valve, open the front valve, open the high vacuum valve, and vacuum the furnace.
5. When the heating on the control cabinet is illuminated, turn the heating power knob to the open position so that the furnace can be heated up.
6. When the heating process curve is completed, the furnace body is heated. Wait for the furnace to cool naturally. If it needs to be cooled quickly, the temperature can be reduced to a certain value (according to the process curve), the valve is closed, the front valve is closed, and the two mechanical pumps are closed.
7. Now open the backfill valve and open the equalizer valve. When the backfill pressure set value is backfilled, the backfill valve is automatically closed; The pressure valve is automatically closed when all pressure is pressed to the pressure setting value.
8. Open the inlet and outlet valve. When the inlet and outlet valve is in place (the indicator light on the panel is on), turn on the cold fan knob to force the cooling. When cooled to the location of the process need to stop the strong cold air blower, strong cold air blower (about 2 minutes) after the full stop, shut in and out of the air valve, close the backfill valve, close the equalizing valve, open surprises valve, the furnace charge air.
9. Open furnace door and remove welding parts. A cycle ends.