The Influence Of Various Factors Of Vacuum Furnace On Product Quality

Vacuum is divided into physical vacuum and industrial vacuum two kinds.Physical vacuum refers to the space where no particles exist. Industrial vacuum refers to the gas space with pressure smaller than a standard atmosphere. It refers to the rareous gas state.The vacuum of vacuum furnace belongs to industrial vacuum.

Tightly squeezed vacuum seal:As we all know, the more belong to parts of vacuum heat treatment were carried out within the airtight vacuum furnace, thus, obtain and shake the leak rate due to the stove, ensure that does not make the vacuum degree of vacuum furnace, vacuum heat treatment to ensure parts quality most has very important significance, so a key problem of vacuum heat treatment furnace, vacuum sealing structure, reliable itIn order to ensure the vacuum performance of the vacuum furnace, a basic principle must be followed in the structural design of the vacuum heat treatment furnace, that is, the furnace body should be used for gas-tight welding, and at the same time, the furnace body should be opened or not opened as much as possible, and the dynamic seal structure should be used or avoided to minimize the opportunity of vacuum leakage.The parts and accessories installed on the vacuum furnace body, such as the water-cooled electrode and the exported thermocouple stomach, must also be designed with sealing structure.

The vacuum system consists of diffusion pump, mechanical pump, main way valve, high vacuum flapper valve and bypass valve.Mechanical pump is a coarse vacuum device, its power source is a three-phase ac motor, through the ac contactor disconnect and suction to achieve the pump stop and work.The high vacuum oil diffusion pump is a high vacuum device, with the help of the diffusion pump oil, the pre-stage mechanical pump and the role of electric furnace heating to complete the high vacuum requirements of the pumping work, through the ac contactor disconnect and suction control of the electric heating furnace, and then control the diffusion pump stop and action.

Dependence on people in the process of control brings instability.Due to the long production cycle, influenced by people’s emotions, experience, sense of responsibility, fatigue, etc., the quality is difficult to guarantee;The outdated monitoring instrument and inaccurate measurement data seriously affect the quality of products.Foreign vacuum heat treatment technology developed in the 1950s, in which the high temperature vacuum furnace, mostly used for smelting, gold treatment and other aspects, mainly with coke as fuel.And the low temperature vacuum furnace is mainly electric heating baking, electric heating treatment energy consumption is low, the price is cheap.Generally, low-temperature vacuum furnace is used to bake the body of power transformer.By the 1970s, foreign heat treatment of metals, such as melting, gold and other aspects of the high temperature vacuum furnace has begun to use microcomputer control and programmable controller, the power transformer baking used low temperature vacuum furnace for power temperature control and solid state temperature control.There is still some distance between process control and production automation.

Vacuum furnace structure, temperature control, heating process and furnace atmosphere, will directly affect the quality of the vacuum furnace after production.In the forging furnace, increasing the temperature of the metal can reduce the melting resistance, but too high temperature will cause the oxidation or overburning of grains, which seriously affects the quality of the products in the vacuum furnace.In the process of heat treatment, if the steel is heated to a certain point above the critical temperature, and then the sudden use of cooling cooling, the hardness and strength of the steel can be improved;If it is heated to a point below the critical temperature and then cooled slowly, it can be made more ductile.

Editor: Frank Lee

Copyright: SIMUWU Vacuum Furnace