Three basic requirements for vacuum system of vacuum heat treatment furnace:

1) can quickly vacuum the heat treatment furnace to the specified requirements.

2) it can timely discharge all kinds of gases released by the workpiece and furnace internals being processed, as well as gases infiltrating into the furnace body due to vacuum leakage.

3) the vacuum unit covers a small area, operates safely and reliably, and is easy to operate.

Composition of the vacuum system

The vacuum system of vacuum heat treatment furnace usually consists of vacuum acquisition equipment (vacuum pump unit), control vacuum assembly and measuring vacuum assembly.

1) vacuum pump unit. According to the working pressure of the furnace and the amount of air pumped, different low vacuum pumps, medium vacuum pumps, high vacuum pumps and ultra-high vacuum pumps are selected.

2) vacuum components or components. Various vacuum components or true-word elements, such as pipes, seals, flanges, bellows, cold traps, filters and valves, are provided between the vacuum furnace and the vacuum pump unit.

3) vacuum measuring system, such as vacuum gauge, vacuum pressure gauge and other vacuum measuring instruments.

4) vacuum leak detection instrument, vacuum control instrument, inflatable device, etc.

There are many kinds of vacuum furnaces, which have different requirements for vacuum system. In terms of vacuum, there are low vacuum, medium vacuum and high vacuum systems. Several commonly used vacuum systems are described below.

1. Low vacuum system

Low vacuum system is suitable for vacuum heat treatment furnace with vacuum degree in the range of 2 ~ 1333Pa, such as pre-pumped low vacuum well furnace. Most of the oil - sealed rotary mechanical pump pump.

2. Medium vacuum system

Medium vacuum system is suitable for vacuum degree in 3 X10 ~ ~ 1. Vacuum heat treatment furnace in 333Pa range. The middle vacuum system is most widely used in the vacuum heat treatment furnace. The primary pump USES the rotary mechanical pump or the slide valve type mechanical pump, the main pump is the mechanical booster pump (roots pump) or the oil booster pump

3. High vacuum system

High vacuum system is suitable for vacuum degree at 6. 6 times 10 ~ ~ 1. 333 X 10. Pa range of vacuum heat treatment furnace, such as vacuum annealing furnace, vacuum brazing furnace, usually composed of three vacuum pump unit, the main pump is usually used oil diffusion pump, ion pump, the primary pump is mostly used rotary mechanical pump or sliding valve type mechanical pump.