Vacuum carburizing process

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Process: artifacts into the charging station to enter the channel tank – rose to loading chamber after vacuum – transfer artifacts to carburizing chamber and carburizing – down into adiabatic heating workpiece after chamber to gas quenching chamber into the .

Operation points:

(1) loading chamber after loading chamber into the workpiece, the vacuum up to 6 x 102 pa, when the chamber with the channel tank pressure equal, open the vacuum seal valve, the elevator will shift the workpiece down channel inside the tank pressure, and transferred to the carburizing chamber.

(2) heating carburizing chamber and carburizing process:

1. The carburizing temperature 920 ~ 970 ℃ (maximum temperature of 1250 ℃).

2. The speed of the workpiece in the carburizing furnace is 2 revolutions per minute.

3. The formation of C3H8 and N2, and the formation of C3H8 after the pulse of the heat resistant steel nozzle was alternately injected into the furnace. (in the case of strong infiltration period, the time of C3H8 was 1 ~ 4min, and the diffusion time of N2 was 2 ~ 6min, and the subsequent permeability was gradually shortened, and the diffusion period was gradually extended, as shown in the table).

4. The process of carburizing (including carburizing and diffusion) is controlled by four parameters: temperature, time, C3H8 and N2 flow and pressure. According to the technical requirements of the workpiece, the computer simulation is used to determine the technical parameters and realize the automation control of the carburizing process (developing dynamic control technology).

(3) air quenching adopts adjustable (1 ~ 20) x 105Pa high purity N2 in the carburizing furnace to form a cooling channel to cool the workpiece.