AJAX compressor

Ajax integral engine-compressors are gas compressors with built-in two cycle natural gas engine. The slow speed (440 rpm max), simplistic design make this compressor highly reliable, low maintenance and easy to operate. Ajax is the compressor of choice in its power range (105-600 KW) and it is common to see several Ajax machines in one compressor station. Standard features include:






  1. Hydraulic fuel control system: for optimum fuel efficiency.
  2. Babbitt sleeve and/or Double-row tapered roller bearings: for maximum loading in extreme application conditions.
  3. Power cylinders: two-cycle, low-BMEP, chrome-plated, with fewer parts for less maintenance. Require no gas control valves.
  4. Crosshead guides: absorb (relieve) crank stresses on the cylinder and prevent contamination of lube oil in crankcase.
  5. Splash lubrication system: no oil pump, filter or cooler required for main and connecting rod bearings. Oil-bath lubrication system is sealed from combustion process in the cylinders.
  6. Reliable ignition: solid-state, time-based ignition system without distributor.
  7. Efficient lubrication: force-fed lubrication system for power and compression cylinders, with lube point injection and divider block.
  8. Crosshead structure with Babbitt facing at both the power and the compressor ends.
  9. Crankshaft and Connecting rods: closed-die forged in precision dies.
  10. Crankcase: ribbed, cast iron construction for durability.
  11. Distant piece (intermediate casing): API-Type II extra-length design for easy rod packing maintenance.
  12. High rod load and cylinder working pressure: full-load operation through a variety of compression ratios up to 6:1 per stage.
  13. Compressor cylinders: large gas passages and valve flow areas for high efficiency.
  14. High-quality differential poppet valves.
  15. Cylinder clearance/loading regulation: manual, hand-wheel type, variable-volume extra clearance pocket with indicator allows the cylinder unloading without de-pressurizing.


The model line of Ajax compressors includes four basic models (according to the number of power cylinders: DPC 2801, DPC 2802, DPC 2803, DPC 2804). Maximum shaft power for the largest compressor DPC 2804 is about 600 kW.


Ajax integral reciprocating engine-compressor set consists of:

  1. Integral reciprocating engine-compressor for gas compression comprising reciprocating compressor and reciprocating gas-fueled engine drive.
  2. Integral compressor frame mount (skid). The steel skid is mounted and secured on a foundation plate fabricated according to the manufacturer’s drawings. The steel skid is built for heavy-duty service and designed to carry reciprocating compressor with gas engine drive including auxiliary systems and process equipment.
  3. Separators (scrubbers) – one set at the inlet to compression stage and another set at the outlet from aftercooler section – provide 95% efficiency for separation of liquid droplets larger than 5 µm. Each separator is equipped with a pressure-relief valve which is mounted directly on the separator or on the connecting piping, automatic drain valve, and condensate level gauges for the automatic high-level emergency tripping system.
  4. Suction and discharge surge tanks are provided at the inlet and discharge connections. Gas flow pulsations occurring during the operation of reciprocating compressor are dampened in surge tanks and supply pipelines which are designed and intended to suppress pressure fluctuations up to +\-5% of the peak ratio 2.5:1 under standard gas conditions. Discharge surge tanks are fitted with suitable connections for drain lines, pressure and temperature gauges.
  5. Oil lubrication system for compressor and engine crankcase and power and compression cylinders comprising the following:
    • Lube oil crankcase for lubrication of crankshaft, bearings and crossheads
    • Lube oil storage tank for lubrication of cylinder faces and gland seals of compressor and drive rods
    • Main lubricator driven by crankshaft for oil supply to the cylinders
    • Instrumentation for lube oil system performance monitoring
    • Lube oil piping set
    • Hand pump for pre-lubrication of main bearings, connecting rod bearings and crossheads
    • Pre-lubrication and lube oil pre-heating system with oil supply to crankshaft, bearings and crossheads
    • Thermostatic valve
    • Oil level regulator and low-level switch
    • Pressure-relief device (safety valve)
  6. ALTRONIC III Ignition System comprising the following:
    • Shielded, contactless, synchronized ALTRONIC III ignition system
    • Ignition coil
    • Electric wiring. All wires enclosed in protective sheath to prevent mechanical damage
    • Electronic speed governor
    • 24 V generator actuated by power transmission from the crankshaft.
  7. Compressor monitoring and control system comprising the following:
    • Shielded wiring, normally-open
    • Supervisory and indicating instrumentation
    • Centurion controller and a digital display of Murphy make for monitoring (and emergency tripping) of the following parameters:
    • Exhaust temperature in each cylinder
    • Suction and discharge pressure, intermediate pressure at each compression stage
    • Water temperature in compressor and engine cooling jacket
    • Temperature of crankshaft main bearings
    • Compressor discharge temperature and pressure
    • Liquid level in scrubbers
    • Failure of lube oil supply to compressor and engine cylinders
    • Oil level in drip pan
    • Crankshaft rotation speed
    • Starting counter
    • Vibration of engine drive and air cooler.
  8. Compressor drive pneumatic starting system comprising the following:
    • Pneumatic motor
    • Set of supply piping
    • Ball valve
    • Pressure-relief valve.
  9. Compressor and power drive cooling system comprising the following:
    • Crankshaft-driven cooling water pump.
  10. Gas air cooler of prefabricated, modular design comprising the following:
    • Liquid cooler section for compressor and engine cylinders cooling system
    • Compressed gas cooling section (according to the number of compression stages)
    • Fan with V-belt motor drive
    • Set of piping and flange connections to the main lines
    • Casing with skid (frame) for housing all equipment above listed
    • Air cooler located outside the main compressor skid on a separate foundation.
  11. Fuel gas injection system. Patented, cam gear-actuated hydraulic fuel injection system provides optimum fuel efficiency. Fuel preparation technology based on "internal carburation system" makes it completely unnecessary to employ any additional devices for reduction of hazardous emissions. Dual ignition (with antechamber) is designed to ensure complete fuel combustion resulting in less generation of NOx.
  12. Drive exhaust system comprising the following:
    • One silencer for power drive exhaust system (vertically mounted on the common skid) with pipe connections to cylinder exhaust manifolds.
  13. Compressor piping system comprising the following:
    • Complete set of interstage piping for connection of compressor gas path elements from the suction drum inlet flange to the discharge stage outlet flanges
    • Complete set of control and shutoff valves
    • Bypass (crossover) pipeline complete with shutoff and control valves
    • Complete set of gas pressure-relief valves installed on separators or directly on the connecting piping of compressor unit
    • Fuel gas pipeline complete with pressure regulator, pressure-relief valve, fuel filter, fuel valve and pressure gauge.





    • Reciprocating compressors supplied by Premium Enginering

      Novatek-Tarkosaleneftegaz, 2004


      Reciprocating compressor with gas engine for pumping natural gas

      Power: 1.2 MW


      Lukoil-Odessky oil refinery, 2006


      Reciprocating compressor with electric motor for refining hydrogen rich gases

      Power: 1 MW


      TNK-BP, Saratovsky oil refinery, 2006-2011


      2 reciprocating compressors with electric motor for refining hydrogen rich gases

      Power: 1 MW each


      Ukrgazdobycha, 2006


      Reciprocating compressor for gas re-injection with gas engine

      Power: 300 KW


      Condensat, 2008


      2 reciprocating compressors with electric motor for the pumping of flare gases with high content of acid components into high-pressure pipeline

      Power: 500 kW each


      Tatneft, Minnibaevsky gas processing plant, 2010


      4 compressors with electric motor to compress commercial products

      Power: 0.6-3.5 MW




      Centrifugal compressors

      The main advantage of the centrifugal compressor is the complete absence of oil in the compression stage, and, therefore, in the compressed medium. This type of compressor can handle large amounts of gas, even though it is compact in size and relatively light-weight. 

      The centrifugal compressor is easy to run and can operate up to five years without shutdown. In addition, the unit cost of compressing one cubic meter of gas will be equal to, or lower than, the unit cost in reciprocating or screw-type compressors. 

      Centrifugal compressors have been successfully used in the gas, chemical, petrochemical, glass industry, metallurgy, heavy machinery manufacturing and in many other industries where gas with no admixture of oil is necessary and medium to large volumes of compressed gas with low to medium pressure are required. 

      Premium Engineering delivers compression solutions that are efficient and economic. Top industrial companies throughout Russia and the CIS testify to the performance and quality of our equipment and its assembly. 

      Advantages of multi shaft centrifugal compressors

      • Axial loads from high speed impellers are transferred to the low speed shaft and absorbed by low speed bearings providing inherent mechanical stability
      • Compact design and smallest footprint
      • High quality bull gear and pinion ensures lifetime warranty
      • No mechanical contact between air and oil seals
      • Minimum wear of rotating parts
      • No replacement of main parts
      • Absence of oil prevents contamination of compression medium
      • Absence of vibration ensures stable operation
      • No special foundation needed
      • Long service life


      Principal features of centrifugal compressors




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