Can a tube furnace be equipped with a vacuum pump?

A tube furnace can be equipped with a vacuum pump, but it needs to be designed and operated reasonably based on equipment structure, process requirements, and safety regulations. Let’s take a detailed look below!

A commonly used vacuum tube furnace (click on the image to view product details)

1.Technical feasibility
Structural adaptability
The furnace tubes of tubular furnaces (such as quartz, corundum, or metal materials) usually have a certain degree of sealing and can be connected to vacuum pumps through flanges or sealing interfaces. Some tube furnaces (such as rotary tube furnaces and vacuum atmosphere furnaces) have reserved vacuum interfaces that can be directly connected to the vacuum system.
Vacuum degree requirement
Low vacuum application: If simple degassing or atmosphere replacement is required (such as 10 ⁻¹~10 ⁻³ Pa), mechanical pumps or dry pumps can meet the requirements.
High vacuum requirement: If ultra-high vacuum is needed (such as below 10 ⁻⁴ Pa), a molecular pump or turbo pump group should be configured, and a front-end mechanical pump should be used.
processing compatibility
Vacuum environment can prevent material oxidation and is suitable for atmosphere sensitive processes such as metal sintering, semiconductor film deposition, catalyst preparation, etc. For example, in the preparation of lithium-ion battery materials, a vacuum environment can reduce the introduction of impurities and improve material purity.

2.Key precautions
Sealing and leakage control
Metal seals (such as CF flanges, KF flanges) or high-temperature resistant rubber rings (such as fluororubber) should be used at the connections between furnace tubes, flanges, valves, etc., to ensure a leakage rate of ≤ 10 ⁻⁹ Pa · m ³/s.
Regularly check the leakage rate of the vacuum system to avoid insufficient vacuum caused by seal failure.
Material temperature resistance and gas release
The furnace tube material needs to withstand process temperatures (such as quartz tubes with a temperature resistance of ≤ 1200 ℃) and have a low gas release rate at high temperatures.
After the first use or long-term shutdown, the furnace tube needs to be baked and degassed (such as maintaining 200 ℃ for 2 hours) to reduce the release of adsorbed gas on the inner wall.
Safety and operational standards
Pressure protection: Install vacuum gauges (such as Pirani or ionization gauges) to monitor pressure in real time, and configure explosion-proof valves or safety valves to prevent furnace tube rupture due to excessive internal and external pressure differences.
Operation sequence: Vacuum first and then heat up to avoid explosion caused by residual oxygen at high temperatures; After cooling, the vacuum should be slowly broken to prevent the furnace tube from cracking due to thermal stress.
Inert gas protection: After vacuuming, high-purity nitrogen or argon gas should be filled as a protective gas to prevent material oxidation.

3.Typical application scenarios
material synthesis
Metal powder sintering: Sintering titanium alloys and nickel based alloys under vacuum to avoid performance degradation caused by oxidation.
Semiconductor thin film deposition: High purity silicon carbide and gallium nitride thin films are prepared by chemical vapor deposition (CVD) using a vacuum pump to maintain a low oxygen environment.
Heat treatment process
Annealing and stress relief: Annealing metal parts under vacuum or inert atmosphere to eliminate processing stress and improve toughness.
Degassing and Purification: Vacuum degassing of porous materials (such as activated carbon and zeolite) to enhance adsorption performance.

4. Equipment selection suggestions
Vacuum pump type
Mechanical pump: suitable for rough vacuum (10 ⁵~10 ⁻ ² Pa), low cost, but oil vapor may contaminate the system.
Dry screw pump: No oil pollution, suitable for processes such as semiconductors and lithium batteries that require high cleanliness.
Molecular pump: Paired with a front-end pump, it can achieve ultra-high vacuum (below 10 ⁻⁴ Pa), but the price is relatively high.
Supporting equipment
Vacuum gauge: Choose a thermocouple gauge or ionization gauge based on the pressure range to ensure measurement accuracy.
Valves and pipelines: Full metal angle valves or VAT valves are used, and the inner wall of the pipeline needs to be polished to reduce gas adsorption.

Rotating tilting tube furnace with mechanical pump (click on the picture to view product details)

In general, a tube furnace can be equipped with a vacuum pump. Before purchasing, it is recommended to communicate with relevant technical personnel about the parameters you need, so as to buy a more suitable vacuum tube furnace for yourself!Click to learn more tube furnaces! Or click on online customer service to learn more about product information!