A method for manufacturing a high-speed vacuum brazing furnace.

To prevent oxidation of the welding joints, the brazing process is usually carried out in a vacuum environment or protective gas. Brazing can be completed by heating the entire workpiece, welding multiple workpieces and multiple seams at once, which improves welding productivity. However, the existingvacuum brazing furnacehas a complex structure, slow vacuum heating speed, and brazing operation time can even last for several hours, severely restricting the production efficiency and promotion of brazing.

Technical implementation elements: In response to the above situation, technicians have designed a high-speedvacuum brazing furnace, which accelerates the vacuum extraction and heating speed of the brazing furnace, greatly improving brazing efficiency. To achieve the above objectives, this vacuum brazing furnace adopts the following technical scheme: a high-speed vacuum brazing furnace, including a shell, with the front side of the upper part of the shell as an operation platform and the rear side as an electrical cabinet. The operation platform is embedded with a vacuum heating furnace, the furnace body is hidden below the operation platform, and only the top cover is exposed above the operation platform, saving space, facilitating operation, and being neat and beautiful. It is matched with the control panel on the front panel of the electrical control cabinet, facing the operation platform, making it convenient to adjust the voltage and current of the vacuum heating furnace during the brazing process. The front panel of the electrical control cabinet is equipped with a control panel, a transformer for powering the vacuum heating furnace, a pre-extraction pump, and the interior of the shell is equipped with a maintenance pump and a molecular pump for vacuum extraction of the vacuum heating furnace. The external part of the vacuum heating furnace is equipped with a water-cooled interlayer, the top of the vacuum heating furnace is equipped with an openable top cover, and the bottom is equipped with a temperature sensor.

vacuum brazing furnaceOn both sides of the vacuum heating furnace, there are two copper electrodes, one end of each copper electrode extending into the vacuum heating furnace is connected to a graphite clamp, and a graphite heating plate is set on the bridge between the two graphite clamps. The other end of the two copper electrodes is connected to the output terminal of the transformer; the rear wall of the vacuum heating furnace is equipped with a pre-extraction vacuum port, a vacuum maintenance port, a gas filling port, and an exhaust port; the water-cooled interlayer of the vacuum heating furnace is equipped with a water inlet and a water outlet. The pre-extraction pump is connected to the pre-extraction port to perform pre-extraction vacuum on the vacuum heating furnace. The pre-extraction pump pipeline is equipped with a pre-extraction valve and a resistance meter two. The molecular pump is connected to the vacuum maintenance port. The maintenance pump and the molecular pump are connected in series to achieve deep vacuum extraction of the vacuum heating furnace.

A maintenance valve and a resistance meter one are set on the pipeline between the maintenance pump and the molecular pump, and a main valve and an ionization gauge are set on the pipeline between the molecular pump and the vacuum heating furnace. This is used to fill protective gas into the vacuum heating furnace, and its pipeline is equipped with a gas filling valve and a pressure gauge one. The water inlet of the water-cooled interlayer is externally connected to a cooling pump, and its pipeline is equipped with a water flow switch and a pressure gauge two. The electrical control box is equipped with a PLC controller for the high-speed vacuum brazing furnace and an SCR power regulator to adjust the input voltage of the transformer. The control screen is equipped with a temperature controller, an electronic pressure gauge, a vacuum gauge, a molecular pump controller, and an HMI human-machine interface. The vacuum heating furnace is equipped with an upward-opening top cover, and the edge of the top cover is equipped with a sealing strip. When placing the object to be brazed, the top cover can be easily opened. During brazing, the top cover is fastened, and the sealing strip plays a good sealing role. When vacuuming in the vacuum heating furnace, due to the pressure difference inside and outside and the good sealing effect of the top cover, the top cover will be pressed tighter, resulting in better sealing.

The beneficial effects of the abovevacuum brazing furnace: The vacuum brazing furnace has a simple structure, reasonable design, and adopts a new method of vacuum heating graphite plates, greatly improving the vacuum extraction and heating rates. The joints are smooth and flat, with little change in microstructure and mechanical properties, minimal deformation, accurate workpiece dimensions, capable of welding the same metal as well as different materials. There are no strict limitations on the thickness difference of the workpieces, and multiple workpieces and joints can be welded at once, greatly improving brazing production efficiency.