4M Series High Pressure Natural Gas Compressor — Four-Row Four-Stage Industrial Process Compression

4M Series High Pressure Natural Gas Compression — Four-Row Four-Stage Industrial Reciprocating Compressor

The 4M Series high pressure natural gas compressor delivers the highest gas capacity within the high-pressure product line. Four verified models cover 85 to 150 m³/min at discharge pressures of 3.00 or 4.00 MPa in a four-row four-stage reciprocating configuration. Motor power ranges from 1,000 to 1,700 kW. These are the largest and highest-powered machines in the high-pressure natural gas compressor family.

At 150 m³/min and up to 4.00 MPa discharge, the 4M Series targets industrial-scale process and pipeline duties that require both high gas throughput and substantial pressure elevation. The four-row four-stage design is specifically engineered for this combination: the four-row frame provides the cylinder displacement needed for high gas volume, and the four compression stages distribute the overall pressure ratio across four steps to control per-stage discharge temperature and maintain mechanical reliability at sustained high-load industrial operation.

Operating Range and Configuration

Capacity values are in m³/min as stated in source data. Flow-reference basis must be confirmed for North American sizing in SCFM or MMSCFD. Dual discharge-pressure notation (3.00 or 4.00 MPa) indicates each model is rated for either pressure, with a corresponding difference in motor power requirement.

Available Models and Technical Specifications

All models share the same 6,800 × 3,900 × 3,200 mm frame dimensions. Weight increases incrementally from 26.00 to 27.00 tonnes across the capacity range. The single power value listed for each model is as stated in the source; the specific power at each discharge-pressure rating (3.00 vs. 4.00 MPa) should be confirmed with the engineering team at the time of inquiry. Capacity in m³/min; flow-reference basis must be confirmed.

Four-Row, Four-Stage Construction — How It Addresses High-Capacity High-Pressure Duty

The four-row frame provides four opposing cylinder banks to develop the large combined piston displacement required for 85 to 150 m³/min at discharge pressures of 3.00 to 4.00 MPa. Without the four-row layout, achieving this capacity within a two-row frame at the same discharge pressure would require extremely large individual cylinders, which create mechanical challenges in terms of cylinder force, frame loading, and foundation design.

The four-stage compression arrangement divides the overall pressure ratio into four successive compression steps, with interstage cooling between each stage. At 3.00 MPa discharge from near-atmospheric suction, the overall absolute compression ratio is approximately 30:1. Dividing this across four stages — each handling a ratio of roughly 2.3:1 to 2.5:1 — keeps per-stage discharge temperatures within limits that protect cylinder valves, piston rings, and seals at continuous industrial duty. In contrast, compressing the same gas in two stages would require each stage to handle a compression ratio of approximately 5.5:1, with correspondingly higher discharge temperatures at each cylinder.

Three interstage coolers sit between the four compression stages. Cooling capacity and interstage temperature targets are critical design parameters at this scale. In high-ambient environments or where cooling water availability is limited, the engineering team must evaluate whether the proposed cooling arrangement achieves the required stage-inlet temperatures under the worst-case ambient condition expected at the installation site over the operational life of the machine.

Dual Discharge Pressure Rating

All four 4M Series high-pressure models are rated for either 3.00 or 4.00 MPa discharge pressure. The single power value listed in the table above for each model reflects the source data as presented; in practice, reaching 4.00 MPa requires more compression work than 3.00 MPa at the same flow rate and suction condition, and the power requirement at each pressure level should be confirmed with the engineering team during the inquiry stage.

The dual-pressure design approach allows a project team to select a single machine type for applications where the required discharge pressure may be either 3.00 or 4.00 MPa, which can simplify procurement, reduce spare-parts inventory, and provide operational flexibility if process conditions change after commissioning.

Common Frame, Scalable Capacity

The three smallest models — 4MW-85, 4MW-90, and 4MW-120 — share an identical frame dimension of 6,800 × 3,900 × 3,200 mm at 26.00 tonnes. The highest-capacity 4MW-150 is marginally heavier at 27.00 tonnes but uses the same frame envelope. This common-frame approach simplifies foundation engineering, site layout planning, and maintenance infrastructure across the four model variants. When a project requires a capacity increase — from 85 to 120 m³/min, for example — the footprint and civil requirements remain unchanged, and the change is within the machine’s cylinder and power configuration rather than the external envelope.

Industrial Scale Applications

At 85 to 150 m³/min and 3.00 to 4.00 MPa discharge, the 4M Series high-pressure compressor targets midstream and industrial-scale natural gas compression duties. Gas gathering systems that collect large volumes from multiple well pads and must deliver at pipeline pressure — typically in the 3.00 to 4.00 MPa range on many North American gathering and trunk systems — represent a core application. Gas processing plant recompression, where large volumes of treated gas must be pressurized for export or injection into a transmission pipeline, is another.

Where multiple smaller compressor units would otherwise be required to match the total capacity, a single 4M Series high-pressure unit may simplify the installation by reducing the number of compressor trains, the associated instrumentation, electrical connections, and operator attention required. Whether a single large unit or multiple smaller units is the better approach for a specific project depends on considerations of redundancy, turndown requirements, maintenance access, and site layout — all of which should be assessed early in the project engineering phase.

Site and Electrical Infrastructure

All 4M Series high-pressure models require a 6 kV or 10 kV electrical supply. At 1,000 to 1,700 kW, the motor power demand is among the highest in the natural gas compressor product line. Site electrical planning — including transformer sizing, switchgear rating, cabling, and coordination with the local grid or on-site generation — should be integrated into the project scope from the earliest planning stage. Where the available site supply voltage differs from 6 kV or 10 kV, this must be discussed with the engineering team before equipment selection is finalized.

The 26 to 27-tonne bare-machine weight requires engineered foundation design for the compressor skid and associated equipment. The full package weight — including motor, gearbox if applicable, piping, coolers, separators, and control panel — will be higher than the bare-machine figures in the table. Foundation loads and anchor bolt arrangements should be confirmed with the engineering team once the package scope and layout are defined.

Gas Composition and Process Conditions

At 4.00 MPa discharge pressure with a high gas volume, the engineering requirements for material selection, seal design, and valve specification are more demanding than in the low-pressure product family. Gas composition — particularly the content of CO₂, H₂S, heavy hydrocarbons, and liquid water — must be fully disclosed before equipment configuration and materials are finalized. Elevated H₂S concentrations at high discharge pressure increase the partial pressure of H₂S at the cylinder outlet and in the discharge piping, which raises corrosion risk and may require material upgrades, specialized packing, or specific seal compounds. The engineering team must evaluate these factors for the specific gas stream.

The potential for hydrocarbon condensation at any point in the interstage cooling system — where gas is cooled between stages and heavy components may drop out of the vapor phase — is also an important design consideration at this capacity and pressure level. Interstage separators and appropriate liquid management systems are standard practice in high-pressure multi-stage reciprocating compressor packages for natural gas service.

Information Required for Compressor Selection

• Gas composition (full component breakdown including inerts)
• Methane, CO₂, and H₂S content
• Heavy hydrocarbon content and dew-point information where available
• Suction pressure and suction temperature
• Required discharge pressure (3.00 or 4.00 MPa)
• Required flow rate and flow-reference basis
• Site ambient temperature range and altitude
• Continuous or intermittent duty cycle
• Available electrical supply (voltage, frequency, and supply capacity)
• Cooling method and cooling-medium availability
• Hazardous-area classification requirements
• Skid and package requirements
• Redundancy and turndown requirements
• Destination country and project location

Frequently Asked Questions

How does the 4M Series high-pressure compressor differ from the D Series high-pressure at overlapping capacities?
The highest-capacity D Series high-pressure model verified in the source data is the DW-70/30(40) at 70 m³/min. The lowest 4M Series high-pressure model is the 4MW-85/30(40) at 85 m³/min. In that capacity range there is no direct overlap between the two series; they are complementary rather than competing. The structural difference — two-row for the D Series versus four-row for the 4M Series — means the 4M Series distributes the cylinder arrangement differently, which affects the machine’s footprint geometry and the distribution of cylinder loads across the frame.

Can the 4M Series high-pressure compressor be used in parallel operation?
Multiple reciprocating compressors operating in parallel on a common suction and discharge header is standard practice in gas processing and pipeline service. The engineering considerations for parallel operation — including capacity control to prevent recycle, pressure balancing, and isolation valve design — should be reviewed with the engineering team as part of the detailed process design. Whether parallel 4M Series units are preferable to a single large unit versus multiple smaller D Series units depends on the project’s redundancy requirements, total capacity, and operational flexibility needs.

What is the realistic continuous duty cycle for a machine at this power level?
The source data does not specify duty cycle ratings for the 4M Series. For industrial natural gas compression at this scale, continuous 24/7 operation is the typical design basis in pipeline and gas processing applications. Maintenance intervals, valve inspection schedules, and planned shutdown requirements depend on the specific operating conditions, gas composition, and the maintenance regime applied. The engineering team can advise on planned maintenance requirements based on the confirmed operating parameters and applicable industry practice for machines of this type.

Request a Technical Proposal

The 4M Series high-pressure natural gas compressor is an industrial-scale machine requiring a thorough engineering review before a technical proposal can be prepared. Provide gas composition, suction pressure and temperature, required discharge pressure, required flow rate with the flow-reference basis, site electrical supply details including voltage and available capacity, cooling-medium availability, ambient temperature range, altitude, and any hazardous-area or package requirements. With these inputs, the engineering team can evaluate the four-stage compression arrangement, confirm motor selection and electrical infrastructure requirements, review the interstage cooling design, and prepare a complete technical proposal covering equipment scope, dimensions, foundation requirements, and delivery terms.

Related Compressor Products

• D Series High Pressure Natural Gas Compressor — two-row multi-stage, medium-capacity models at 25–70 m³/min
• L Series High Pressure Natural Gas Compressor — lower-capacity high-pressure models at 6–25 m³/min