Why is the compression ratio for Hydrogen lower than for Nitrogen in turbo pumps?

The pumping effect relies on momentum transfer. Hydrogen molecules have high thermal velocities, reducing the relative speed difference between the molecule and the blade. This increases the probability of back-diffusion. AIMRSE uses Holweck drag stages and high rotational speeds to maximize light gas compression.

Turbomolecular Pump

Q: What are the fore-vacuum requirements for a Turbo Molecular Pump?

TMPs require a backing pump to maintain fore-vacuum pressure usually below 100 Pa, as they cannot exhaust directly to atmosphere. For UHV and cleanroom applications, a dry scroll or Roots pump is recommended to maintain a hydrocarbon-free vacuum chain.

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Cat	Products Name	Key Features
VGE-TP-011	Turbomolecular Pump 1300Ls-24000RPM-390W	Optimized motor; Enhanced cooling; Reliable seals
VGE-TP-012	Turbomolecular Pump 700Ls-36000RPM-220W	High rotation speed; Compact size; Low heat
VGE-TP-013	Turbomolecular Pump 700Ls-36000RPM-230W	Advanced bearings; Smooth operation; Energy saving
VGE-TP-014	Turbomolecular Pump 110Ls-42300RPM-60W	Portable design; Ultra compact; Low consumption
VGE-TP-015	Turbomolecular Pump 295Ls-51000RPM-120W	Extreme speed; Precision control; Minimal footprint
VGE-TP-016	Turbomolecular Pump 140Ls-51000RPM-70W	High frequency; Low weight; Easy maintenance
VGE-TP-017	Turbomolecular Pump 82Ls-72000RPM-45W	Maximum speed; Ultra portable; Precision built
VGE-TP-018	Turbomolecular Pump 20Ls-36000RPM-25W	Entry level; Compact pump; Budget friendly
VGE-TP-019	Turbomolecular Pump 3260Ls-24000RPM-850W	Maximum capacity; Heavy duty; Industrial strength
VGE-TP-020	Turbomolecular Pump 2950Ls-24000RPM-780W	High volume; Robust motor; Thermal management

High-Speed Turbo-Molecular Pumping

Generating Ultra-High Vacuum (UHV) environments necessitates the efficient transfer of momentum to gas molecules within the molecular flow regime. AIMRSE turbo-molecular pumps (TMP) represent the vanguard of kinetic vacuum generation, utilizing high-velocity rotor architectures to achieve compression ratios exceeding $10^{11}$ for Nitrogen. By operating at rotational frequencies where the blade tip velocity approaches the mean thermal velocity of gas molecules, our pumps effectively "sweep" gas species from the inlet toward the fore-vacuum stage.

Engineered for absolute process purity, AIMRSE molecular pumps provide a strictly hydrocarbon-free environment, making them indispensable for semiconductor lithography, surface science research, and particle accelerators. Whether utilizing hybrid ceramic bearings or advanced active magnetic levitation (Mag-Lev) systems, our pumps ensure ultra-low vibration levels and long-term operational stability. With integrated digital control logic and optimized blade geometries, we provide the performance required to sustain base pressures in the $10^{-8}$ Pa range for the world’s most demanding vacuum applications.

Consult Our Kinetic Specialists

Discuss your compression ratio requirements for light gases and vibration isolation constraints with our senior engineering team.

Global technical support available within 24 hours.

Momentum Transfer Physics & Molecular Throughput

Optimized Blade Geometry & Gaede Principle

The pumping efficiency of a TMP is a direct function of blade angle and rotor speed relative to gas molecule velocity. AIMRSE rotors feature multi-stage blade geometries optimized via finite element analysis to maximize the probability of molecular transmission toward the exhaust. This ensures high pumping speeds for heavy molecules while maintaining the high-compression limits necessary for deep vacuum attainment.

Light Gas Compression (He/H₂)

Light gases like Hydrogen and Helium have high thermal velocities, making them difficult to compress kinetically. Our molecular pumps integrate specialized Holweck drag stages following the turbomolecular stages. This hybrid architecture increases the compression ratio for light gases by several orders of magnitude, preventing back-diffusion and allowing for lower base pressures in UHV systems.

Magnetic Levitation & Vibration Damping

For applications requiring absolute mechanical silence, AIMRSE offers active magnetic levitation bearing systems. By suspending the rotor in a 5-axis magnetic field, we eliminate mechanical contact and lubricant requirements. This architecture not only eliminates vibration-induced noise in sensitive analytical tools but also facilitates maintenance-free operation across years of continuous 24/7 duty cycles.

The Advantages of AIMRSE

Precision-engineered for uncompromised throughput and molecular purity.

XHV/UHV Attainment

Achieves verified ultimate base pressures below $10^{-8}$ Pa, providing the environment necessary for quantum research and nanoscale fabrication.

Vibration Isolation

Active Mag-Lev technology ensures sub-micron vibration displacement, critical for electron microscopy and high-resolution beamlines.

Dry Vacuum Purity

100% oil-free pumping chamber prevents hydrocarbon back-streaming, ensuring no carbon contamination of sensitive process optics or samples.

Intelligent Control

Smart onboard electronics provide real-time monitoring of rotational speed, bearing temperature, and motor current with automated protection logic.

Standards & Metrology Compliance

The performance metrics of AIMRSE turbo-molecular pumps are strictly verified against international vacuum technology standards. Pumping speed and compression ratio measurements are conducted in accordance with ISO 21360-2 and ISO 5302. Every unit is balanced to meet the stringent vibration tolerances of ISO 1940-1. Our pumps are designed to meet SEMI S2 safety guidelines for integrated semiconductor manufacturing and comply with CE and RoHS directives for global laboratory safety. All vacuum integrity seals are verified via NIST Traceable helium leak testing, ensuring reliability in the most sensitive Ultra-High Vacuum architectures.

Technical FAQ

Why is the compression ratio for Hydrogen significantly lower than for Nitrogen in turbo pumps?

The turbomolecular pumping effect relies on momentum transfer from the moving blades. Light molecules like Hydrogen have high thermal velocities, meaning the relative speed difference between the molecule and the blade is smaller. Consequently, the probability of a light molecule being reflected backward toward the inlet is higher, leading to a lower compression ratio ($K$). AIMRSE pumps mitigate this by using high rotational speeds and specialized Holweck drag stages to improve light gas throughput.

What is the benefit of a Magnetic Levitation (Mag-Lev) bearing over a hybrid ceramic bearing?

Hybrid ceramic bearings use oil or grease lubrication and have a finite mechanical life due to wear. Mag-Lev bearings use 5-axis active magnetic suspension to eliminate physical contact. This ensures zero mechanical wear, absolute oil-free operation, and ultra-low vibration (displacement $< 0.01$ μm). Mag-Lev pumps are preferred for 24/7 fab environments and high-resolution imaging tools where downtime and vibration are unacceptable.

What are the fore-vacuum requirements for a Turbo Molecular Pump?

TMPs cannot exhaust gas directly to atmospheric pressure. They require a backing pump to maintain a fore-vacuum pressure typically below $100$ Pa (depending on the pump model and gas load). For cleanroom and UHV applications, AIMRSE recommends using a dry scroll or multi-stage Roots pump as a backing stage to maintain a completely oil-free vacuum chain.

Related Products

Note: Our vacuum equipment is for research and industrial testing only. Industrial-grade components are fully rated for field deployment.

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