Almig VMXa 237 R (VMX 110RD) Rotary Screw Air Compressor Stage

Almig VMXa 237 R (VMX 110RD) Rotary Screw Air Compressor Stage (55 kW – 110 kW)

The Almig VMXa 237 R (also designated under the Aerzen system platform as VMX 110RD) is a heavy-duty, single-stage, oil-injected rotary screw air compressor airend engineered for continuous heavy-industrial and marine engine-room duties. Designed to absorb power inputs between 55 kW and 110 kW across drive speeds of 1,200 to 7,500 RPM, this twin-shaft positive displacement unit provides volumetric delivery rates from 7.5 m³/min to 17.5 m³/min (265 to 618 CFM) at working gauge pressures up to 13 bar(g).

The VMXa 237 R features asymmetrical precision-machined steel rotors ($C45N male rotor, GGG 60 nodular cast iron female rotor) enclosed within a high-density GG 20 gray cast iron housing. Operating without timing gears, driving torque is transferred directly or via V-belt/gearbox to the male rotor shaft. Forced oil injection handles sealing, cooling, and hydrodynamic lubrication of the heavy-duty roller and thrust bearings, maintaining optimal discharge gas temperatures near 85°C without requiring an auxiliary oil pump.

Model Details

• Manufacturer: ALMiG Kompressoren GmbH
• Current Model Designation: VMXa 237 R (Direct Drive / Belt Drive execution)
• Legacy / Alternate Model Designation: VMX 110RD
• ALMiG OEM Part Number (MPN): F220.00053
• AERZEN Core Part Number: 152862000 / VMXa237R
• Assembly Type: Single-Stage Oil-Injected Rotary Screw Compressor Stage

Key Features

• Wide Power Range (55–110 kW): Accommodates variable drive configurations with delivery capacities up to 17.5 m³/min (618 CFM) at 13 bar discharge.
• Differential-Pressure Lubrication: Eliminates the need for an external mechanical oil pump; oil is injected directly via internal pressure differentials.
• Heavy-Duty Bearing System: Fitted with precision radial cylindrical roller bearings and axial angular contact ball bearings for a nominal B10 bearing life exceeding 40,000 hours.
• VFD & Frequency Converter Compatible: Dynamic speed capability (1,200 to 7,500 RPM) enables smooth operation across variable frequency drives.

Equipment Compatibility

The Almig VMXa 237 R / VMX 110RD replacement stage is directly compatible with the following stationary and marine air compressor skid configurations:

• ALMiG Variable Speed & Fixed Speed Series: Variable 110, Variable 90, Direct 110, Direct 90, Gear 110 series compressors.
• AERZEN OEM Packaged Systems: Aerzen VMX 110RD assemblies and custom OEM compressor packages.
• Marine Service Compressors: High-output starting air and service air packages used aboard commercial vessels and offshore platforms.
• Custom OEM Packaged Skids: Fits packagers utilizing standard Aerzen VMXa 237 R foot mounts and flange patterns.

Applications

• Marine Main Service Air Systems: Continuous compressed air supply for pneumatic control systems, engine room automation, and deck machinery.
• Industrial Manufacturing Plants: Central compressed air stations delivering reliable 7–13 bar process air.
• Mining & Heavy Construction: Integrated into ruggedized mobile compressor units driven by diesel engines.
• Chemical & Petrochemical Processing: Pneumatic conveying and instrumentation air supply skids.
• Power Generation Facilities: General service air and turbine purging systems.

Frequently Asked Questions

What is the difference between Almig VMXa 237 R and Aerzen VMX 110RD?

They refer to the exact same physical rotary screw compressor stage. Aerzen manufactures the core VMX series airends, and ALMiG designates the unit as VMXa 237 R (Part number F220.00053) for installation across their 55 kW to 110 kW compressor models.

What is the power range and maximum pressure capacity of this airend?

The Almig VMXa 237 R operates across a drive power range of 55 kW to 110 kW (75 to 150 HP) with a maximum permissible operating overpressure of 13 bar(g) (188.5 psi).

Can I run the Almig VMXa 237 R on a Variable Frequency Drive (VFD)?

Yes. All Aerzen/Almig VMX series stages are fully certified for frequency converter (VFD) operation across their dynamic speed range of 1,200 to 7,500 RPM.

What maintenance schedule is required for the VMXa 237 R stage?

Under standard operating conditions with clean air intake filtration and synthetic oil changes performed every 4,000–8,000 operating hours, the VMXa 237 R stage has a nominal major overhaul interval (bearing replacement and seal overhaul) of 20,000 to 40,000 operating hours.