DW Series — Two-column horizontal opposed-balance reciprocating gas compressor. 22 standard models cover 40–400 m³/min at 0.15–2.50 MPa for gas pipeline, low-pressure process, and industrial gas transmission duties.

Product Overview: DW Series Gas Compressor

The DW series gas compressor is a two-column horizontal opposed-balance (opposed-balance) reciprocating piston compressor engineered for the compression of flammable, corrosive, and mixed industrial gases at large volumetric flow rates and low-to-medium pressures. The opposed-balance configuration — with pistons on opposite sides of the crankshaft moving in opposite directions simultaneously — is the defining feature of the DW series, cancelling the primary inertia forces that are the main source of vibration and foundation loading in reciprocating machines at high power levels.

The DW series is specified for gas media including: coal gas (city coal gas), coke oven gas (coke oven gas), blast furnace gas (blast furnace gas), flue gas (flue gas), water gas (water gas), carbon monoxide (CO), biogas (biogas), methane (methane), mixed refinery gas, and similar industrial process and utility gases. The compression medium can contain hydrogen, hydrocarbons, moisture, and incondensable components in varying proportions — the DW series material and sealing specification is selected at the engineering stage to match the specific gas composition of each installation.

22 standard models span 40 to 400 m³/min in flow rate and 0.15 to 2.50 MPa in discharge pressure. The two-column DW models (40–300 m³/min) handle the majority of pipeline transmission and low-pressure process duties. The four-column HW and 4MW extended models (250–400 m³/min, up to 2,300 kW) cover the highest-flow, highest-power duties in the range. All models require 6 kV or 10 kV drive voltage and are available with ATEX explosion-proof electrical equipment for flammable gas service. Manufactured at our production facility in Russia to API 618 Fifth Edition and GOST-R requirements with full Rostechnadzor documentation as standard.

Typical applications: City gas network compression stations, coke oven gas recovery and transmission, blast furnace gas boosting, coal chemical plant mixed gas compression, biogas upgrading plant feed compression, CO gas compression for chemical synthesis, industrial refinery off-gas recovery, mine gas drainage and surface compression, and large-volume process gas transfer.

The Opposed-Balance Advantage at High Gas Flow

At the power levels of the DW series — 355 to 2,300 kW — the dynamic forces generated by reciprocating pistons become a primary engineering constraint. In a single-column or same-direction machine, all pistons move in the same direction at the same moment, producing a large oscillating net force that must be absorbed entirely by the foundation. For a 1,200 kW machine, this net primary force can exceed 150 kN, requiring a foundation mass of 60–100 tonnes and special isolation systems.

In the DW opposed configuration, the pistons on opposite column sides move in opposing directions, and their primary inertia forces cancel at the crankshaft. The result is a net primary force close to zero — the compressor frame transmits only the residual secondary forces and gas pressure reactions to the foundation. Foundation mass is reduced by 50–70% compared to non-balanced designs at the same power, vibration levels transmitted to adjacent pipework and structures are substantially lower, and noise radiated from the compressor frame is reduced. For gas pipeline compressor stations and industrial plants where the compressor is located within or adjacent to existing buildings, this balance advantage frequently determines whether an expansion project is feasible within the existing civil structure.

Technical Specifications — DW Series Low Pressure (0.15–1.00 MPa)

Single-stage two-column configuration for gas pipeline transmission, large-volume low-pressure process gas duties, and industrial gas transfer. The application note on this group: gas media include coal gas, coke oven gas, flue gas, water gas, CO, biogas, methane, and mixed gas with hydrogen content up to 75%.

Note: All low-pressure DW models are single-stage. Pressure notation /8 = 0.80 MPa, /4 = 0.40 MPa, /2.5 = 0.25 MPa, /1.5 = 0.15 MPa. All dimensions L×W×H in mm.

Technical Specifications — DW Series Mid-High Pressure (1.30–2.50 MPa)

Multi-stage configurations for chemical process gas compression, mid-pressure pipeline injection, and high-flow chemical synthesis gas feed at 1.3–2.5 MPa. Application note: gas media include high-hydrogen gas, flue gas, CO, coal gas, biogas, methane, and mixed gas with higher-pressure discharge requirements for chemical processes.

Note: /25 suffix indicates 2.50 MPa discharge pressure (25 bar). DW-60/25 and DW-70/25 use 4-stage compression to achieve the 2.5 MPa discharge from near-atmospheric suction in a single machine. All dimensions L×W×H in mm.

General Series Parameters

Working Principle and Structural Composition

The DW series uses the horizontal opposed-balance reciprocating piston principle. A high-voltage motor drives the crankshaft, which has its two crank throws arranged 180 degrees apart. As one column’s piston moves forward on its compression stroke, the piston on the opposite column simultaneously moves backward on its suction stroke — the inertia forces of the two pistons oppose and largely cancel each other, leaving only the residual secondary forces and gas pressure reactions to be transmitted to the foundation.

For the single-stage low-pressure DW models, each column’s cylinder handles half of the total gas flow independently: suction gas enters both cylinders on their respective suction strokes, is compressed to discharge pressure, and both discharge streams combine at a common outlet header. For the multi-stage mid-high-pressure DW models, the two columns operate as sequentially staged compressors — the larger-bore LP column compresses from suction to interstage pressure, and the smaller-bore HP column receives interstage gas through the intercooler and compresses to final discharge pressure. Four-stage machines (DW-60/25, DW-70/25) achieve the 2.50 MPa discharge from near-atmospheric suction by adding two tandem cylinder bores to each column, providing four compression steps in a single machine pass.

Key Structural Components

Gas Media Guide: Materials and Safety Requirements by Gas Type

The DW series serves a wide range of flammable and industrial gas compositions. Each gas type has specific engineering requirements that are incorporated into the compressor specification at the design stage. The following guide covers the primary gas types in the DW series application range.

Core Advantages of the DW Series

Material Specifications

Selection Guide: Choosing the Right DW Model

DW Series vs. Alternative Machines: Objective Comparison

Factory acceptance test — every DW series unit undergoes a full mechanical run test at rated conditions including vibration measurement and ATEX safety system verification before shipment

Frequently Asked Questions — DW Series Gas Compressor

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Our engineering team has over 70 years of experience manufacturing large reciprocating gas compressors for coal gas networks, coke chemical plants, biogas facilities, and industrial gas pipeline stations across Russia and the CIS. The DW series gas compressor delivers API 618 opposed-balance performance with full GOST-R and Rostechnadzor documentation as standard — with spare parts dispatched from Russia without import delays and on-site service engineers available throughout Russia and CIS.