Universal CNG Compressor, 40 HP, Flow Rate 57 SCFM, Inlet 7 psi to 5000 psi
UsedSpecifications
Description
Universal CNG Compressor, 40 HP, Flow Rate 57 SCFM, Inlet 7 psi to 5000 psi
This is a four-stage reciprocating natural gas compressor built on the W120H-AL air-cooled compressor block, designed to deliver up to 5,000 PSI discharge pressure for CNG applications, gas recovery systems, and industrial gas compression. The unit is rated for 57.7 CFM at 1,200 RPM with an inlet pressure range of 0–7 PSI. It was decommissioned in 2022 after operating normally except that it would not compress above 2,000 PSI; the third stage requires maintenance or repair.
Technical Specifications
Job Number: 20111308
Serial Number: 8003578
Compressor Type: URGT120-40NG / C3
Compressor Block Number: H21191001
Configuration: W120H-AL, air-cooled, reciprocating
Number of Compression Stages: Four
Inlet Pressure Range: 0–7 PSI (1 bar.g)
Delivery Pressure Range: 700–5,000 PSI (100–414 bar.g)
Direction of Rotation: Counterclockwise (viewed from drive end)
Operating Speed Range: 600–1,200 RPM
Displacement: 98.1 m³/hr @ 1200 RPM (≈57.7 CFM @ 1200 RPM)
Safety Valve Settings
1st Stage: 10.0 bar.g (145 PSIG)
2nd Stage: 37.2 bar.g (540 PSIG)
3rd Stage: 161.5 bar.g (2,342 PSIG)
Final Stage: 10% above working pressure
Lubrication System
Force-feed lubrication to crankshaft bearings
Controlled splash lubrication to cylinders
Crankshaft-driven oil pump with full-flow replaceable canister oil filter
Dimensions & Weight
Length: 1,053 mm (41.5 in)
Width: 1,074 mm (42.3 in)
Height: 1,008.5 mm (39.7 in)
Dry Weight: 365 kg (805 lbs)
Design Highlights
The W120H-AL compressor features a “W” form with three cylinders: one double-acting low-pressure piston for stages 1 and 2, and single-acting cylinders for stages 3 and 4. It uses a pedestal-mounted cooling fan that pulls air through the aftercooler/intercooler assembly, maintaining optimal temperatures. Stage-specific relief valves protect the compressor from over-pressure conditions.
Condition
The unit was decommissioned in 2022. It was operational but would not compress above 2,000 PSI. The third stage requires maintenance/repair.
Applications
Ideal for CNG refueling stations, natural gas processing, high-pressure gas transfer, and industrial gas systems where a multi-stage air-cooled reciprocating compressor is required.
- We have all the manuals and schematics for the unit.
Inspection, shipping & payment
Terms set by Gas Equipment 4 Sale.
Price on Request
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Seller
Gas Equipment 4 Sale
Waxahachie, TX, United States
Business and location confirmed by Metal Mountain.
Questions buyers ask
What capacity and discharge pressure does it actually deliver?
The unit is rated for 57.7 CFM at 1,200 RPM with an inlet pressure range of 0–7 PSI and a design discharge pressure of 700–5,000 PSI. It was decommissioned because it would not compress above 2,000 PSI; the third stage requires maintenance or repair. Until the third stage is repaired, it effectively operates as a two-stage compressor limited to approximately 2,000 PSI discharge.
What drive, power and cooling does it require?
The unit is a 40 HP compressor designed to operate at 600–1,200 RPM with counterclockwise rotation (viewed from drive end). It uses air cooling with a pedestal-mounted fan that pulls air through the aftercooler/intercooler assembly. The listing does not specify the motor type, electrical requirements, or drive coupling; ask the seller for the motor nameplate data and whether the motor is included.
What are the running hours and what has been rebuilt?
The listing does not state the operating hours or any rebuild history. The unit was built in 2011 and decommissioned in 2022 after operating normally apart from the third-stage pressure limitation. Ask the seller for the hour meter reading, maintenance records, and any history of valve, piston ring, or packing replacement.
What should I inspect on a used compressor before buying?
On reciprocating compressors, check cylinder bore wear, piston ring condition, valve plate and seat condition on all stages, crankshaft bearing play, and oil pump output pressure. Given the third-stage issue on this unit, inspect the stage 3 piston, rings, and valves closely, and verify the intercooler isn't plugged or leaking. Check all safety relief valves for correct settings and seating, examine the crankcase oil for contamination or metal, and rotate the crankshaft by hand to feel for binding or scoring.
General guidance for this type of equipment. Ask about this specific unit in your inquiry — the seller answers directly.