Working principle of high-temperature electric heating vacuum brazing furnace

04-23-2025       Author: KJ technology

The working principle of the high-temperature electric heating vacuum brazing furnace is mainly based on the combination of vacuum environment, electric heating technology, and brazing process. The following is a detailed explanation:

1. Creating a vacuum environment

Vacuum pumping: The vacuum brazing furnace uses a vacuum pump to evacuate the air inside the furnace, creating a vacuum environment. The vacuum degree can usually reach 10 ^ -3 Pa or even higher to reduce oxidation and contamination, ensuring the quality of brazing.

Vacuum degree maintenance: During the brazing process, the vacuum pump continues to work to maintain a stable vacuum degree in the furnace and prevent air from entering and affecting the brazing effect.

2. Electric heating technology

Heating element: The vacuum brazing furnace adopts electric heating method, and the heating element is usually a resistance wire (such as nickel chromium alloy wire), silicon carbon rod, or graphite heating element. These heating elements generate heat under the action of electric current, converting electrical energy into thermal energy.

Temperature control: The temperature inside the furnace is monitored in real time through temperature sensors such as thermocouples and fed back to the temperature control system. The control system adjusts the power of the heating element according to the set temperature curve to achieve precise temperature control.

Heating rate and uniformity: Vacuum brazing furnaces usually have high heating rates and good temperature uniformity to ensure consistent temperature in all parts of the workpiece during the brazing process and improve brazing quality.

3. Brazing process

Workpiece placement: The workpiece to be brazed is placed on the workbench inside the furnace, and the appropriate placement method is selected according to the shape and size of the workpiece.

Solder selection: Choose the appropriate solder according to the workpiece material and brazing requirements. Solder typically has a low melting point and can melt and fill the gaps between workpiece joints at the brazing temperature.

Brazing process: In a vacuum environment, the heating element raises the temperature inside the furnace to the brazing temperature. The brazing material melts and fills the gap between the workpiece joints at the brazing temperature, forming a firm brazed joint. During the brazing process, a vacuum environment helps to reduce oxidation and pollution, and improve the quality of brazing.

Cooling down: After brazing is completed, turn off the heating element and gradually lower the temperature inside the furnace to room temperature. During the cooling process, the brazed joint gradually solidifies and reaches its final strength.

4. Safety and Protection

Safety device: The vacuum brazing furnace is equipped with comprehensive safety protection devices, such as over temperature protection, leakage protection, overpressure protection, etc., to ensure the safety of the experimental process.

Operating standards: Operators must strictly follow the operating procedures to ensure the normal operation and brazing quality of the vacuum brazing furnace.