Ultra-low pressure in. CNG fill pressure out. One package.The 4-stage NuPresto 400 takes natural gas from suction pressures as low as 40 psig all the way to CNG fill pressure in a single skid. Built for declining wells, low-pressure RNG, and gathering systems where standard 2- and 3-stage packages can’t reach.

Overview The 4-stage NuPresto 400 is engineered for the lowest end of the suction window – 40 to 100 psig – where two or three stages of compression can’t deliver the ratio needed to land at 3,900 psig CNG discharge. Four compression stages, four intercooler sections, and a final aftercooler keep stage temperatures and ratios inside the design envelope across the full operating range.

Mechanically, it is the same NuPresto 400 platform: Fornovo Gas DA300 frame, non-lubricated water-cooled cylinders, PLC controls, and full FAT in shop.

Key Specifications:

• Compression Stages – 4-stage
• Compressor Frame – Fornovo Gas DA300 heavy-duty reciprocating
• Cylinders – Non-lubricated, water-cooled with HP valves
• Suction Pressure – 40 to 100 psig
• Discharge Pressure – Up to 3,900 psig (4,200 psig optional)
• Flow Rate – Up to 1.1 MMSCFD
• Driver – 200 to 350 HP electric motor (depends on suction pressure)
• Rated Speed – 1,200 rpm
• Interstage Cooling – 4-section air cooler plus engine jacket water (EJW) circuit
• Discharge Treatment – Interstage scrubbers and final discharge coalescer
• Cooling Package – Closed-loop glycol with multi-fan air cooler
• Control System – PLC-based with HMI; remote monitoring via Ewon
• Design Standards – ASME Sect. VIII Div. 1, B31.3, NEC, NFPA, API/ISO
• Skid – Single skid, fully assembled and FAT tested in shop

Final flow and power are tuned to your gas analysis, suction conditions, and site requirements. Contact engineering for a sized proposal.

Built for the Lowest Suction Pressures Declining gas wells, low-pressure RNG dryer outlets, and aging gathering systems often deliver gas below 100 psig. The 4-stage NuPresto 400 handles that inlet directly – no separate booster, no field-built workaround.

Four-Section Air Cooler with EJW Engineered air cooler with separate sections for each stage discharge plus engine/jacket water. Stage temperatures stay inside the design window even at 100 °F ambient and 3,000 ft elevation.

Same Frame, Same Controls, Same Service Plan Identical Fornovo DA300 bottom end, control philosophy, HMI, and remote monitoring as the 2- and 3-stage NuPresto 400. Same maintenance intervals on wear parts. Same spares stocked at our shop. Operators trained on one variant are trained on all three.

Non-Lubricated Cylinders No oil carryover into the gas stream. Cleaner downstream equipment, less environmental risk, simpler permitting.

Engineered for Continuous Service Interstage scrubbers, pulsation control, and ASME-stamped vessels and coolers sized for 24/7 wellhead, RNG, and CNG mother station duty.
Built and Tested In-Shop Final assembly, FAT, loop checks, and HMI commissioning happen in our shop. Issues get caught in the shop, not on your site.

Typical Applications
• Declining gas well compression with CNG offtake
• Low-pressure RNG-to-CNG mother stations
• Aging gathering systems and stripper well consolidation
• Pad gas and casinghead gas capture
• Virtual pipeline trailer filling from very low-pressure sources (pairs with NuBlu VPT-64 / VPT-128)
• Stranded gas monetization where pipeline access is limited

What’s Included
• Single skid with 4-stage compressor, motor, multi-section air cooler, and process piping
• Inlet filter, four interstage scrubbers, and final discharge coalescer
• Closed-loop glycol cooling system with EJW circuit
• PLC, HMI, and field instrumentation, wired and tested
• Cause-and-effect diagram, control narrative, and FAT package
• ASME-stamped pressure vessels and coolers, B31.3 piping
• Installation, commissioning, and start-up procedure
• Recommended spare parts list and pricing

Engineering and Aftermarket Support Every 4-stage NuPresto 400 ships with a complete engineering package: P&IDs, GA drawings, electrical load lists, lifting and torsional analyses, and a full O&M manual. Critical spares – including complete cylinders – are stocked at our shop for fast response.
Field service, troubleshooting, and remote diagnostics are handled by the same team that designed and built the unit.

NuPresto 400 Family at a Glance
• NuPresto 400 (2-Stage) → Suction 550 to 950 psig, up to 3.69 MMSCFD, ideal for high-pressure pipeline mother stations
• NuPresto 400 (3-Stage) → Suction 150 to 600 psig, up to 2.6 MMSCFD, ideal for RNG and low/mid-pressure pipeline service
• NuPresto 400 (4-Stage) → Suction 40 to 100 psig, up to 1.1 MMSCFD, ideal for declining wells, low-pressure RNG, and stranded gas

Request a sized proposal Send us your suction pressure, flow target, and discharge requirement, and we’ll come back with a configured 4-stage NuPresto 400 package.