What kinds of vacuum systems are commonly used in vacuum furnaces?
Three basic requirements for vacuum system of vacuum heat treatment furnace:
1) The vacuum degree of the vacuum heat treatment furnace can be pumped to the prescribed requirements quickly.
2) It can discharge all kinds of gases released by the treated workpiece and furnace inner components in time, and the gases infiltrated into the furnace body due to vacuum leakage.
3) Vacuum unit covers a small area, runs safely and reliably, and operates easily.
Composition of Vacuum System
The vacuum system of vacuum heat treatment furnace usually consists of vacuum acquisition equipment (vacuum pump unit), control vacuum module and measurement vacuum module.
1) Vacuum pump unit. According to the working pressure and pumping volume of the furnace, 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 real-character components are equipped between the vacuum furnace body and the vacuum pump unit, such as pipelines, sealing rings, flanges, bellows, cold traps, filters and valves.
3) Vacuum measuring system, such as vacuum gauge, vacuum pressure gauge and other vacuum measuring instruments.
4) Vacuum leak detector, vacuum control instrument, air charging device, etc.
There are many kinds of vacuum furnaces, which require different vacuum systems. In terms of vacuum, there are low, medium and high vacuum systems. Here are some common vacuum systems.
1. Low Vacuum System
The low vacuum system is suitable for vacuum heat treatment furnaces with vacuum degree ranging from 2 to 1333 Pa, such as pre-pumped low vacuum well furnace. Most of them are oil-sealed rotary mechanical pumps.
2. Medium Vacuum System
Medium vacuum system is suitable for vacuum heat treatment furnace with vacuum degree ranging from 3 X10 to 1.333 3a. Medium vacuum system is widely used in vacuum heat treatment furnace, which is usually composed of two-stage vacuum pump units. Primary pumps mostly use rotary mechanical pumps or sliding valve mechanical pumps, the main pump is mechanical booster pumps (Roots pumps) or oil booster pumps.
3. High Vacuum System
The high vacuum system is suitable for the vacuum degree from 6.6 x 10 to 1.333 X 10. Vacuum heat treatment furnaces in Pa range, such as vacuum annealing furnaces and vacuum brazing furnaces, are usually composed of three-stage vacuum pump units. Oil diffusion pumps and ion pumps are usually used in the main pumps, and rotary mechanical pumps or sliding valve mechanical pumps are mostly used in the primary pumps.