The oil and gas industry requires safe and productive solutions for exploration, production, movement, refining and the processing of crude oil and gas products. There is a need for high-quality machinery to siphon crude oil from the earth and efficient equipment for the refinement and distillation processes used to create gasoline, plastics, asphalt and other essential petroleum-based products. This is where the hydraulic compressor shines.

What is a Hydraulic Compressor?

In the oil and gas industry, a compressor is a mechanical device that reduces the volume of a liquid or gas to increase its pressure. It’s used at processing plants, field nodes and inlets of the pipeline. Hydraulic compressors are powerful and lightweight deck-mounted compressors used for low volume and high differential pressure applications such as vapour recovery, gas well boosting and casing gas. 

Types of Hydraulic Compressors:

There are two main types of hydraulic compressors; positive displacement and dynamic.

Positive displacement compressors draw atmospheric air into one or more compression chambers. These chambers are then closed from the inlet. As the volume of each chamber decreases, the air is compressed internally until the pressure reaches the designed pressure ratio. The valve then opens and the air is discharged into the outlet system. 

  • Reciprocating compressors are the most commonly used positive displacement compressors because they can handle all volume capacities and pressures. There are two different designs; single and two-stage.
  • Single-stage: With a single-stage, the air is drawn into the cylinder and compressed in a single stroke. Compressed gas is then transferred to a storage tank
  • Two-stage: A two-stage design employs an extra piston and is capable of higher pressure levels.


Rotary compressors are positive displacement machines in which the compressing and displacement are affected by the positive action of rotating elements. The two main types are vane and screw compressors.

  • Vane compressors use rotating, fan-like blades called vanes to compress hydraulic materials. The size and shape of the vanes determine how strong the pressure can be. Multiple vanes are combined to make complex compressors of any size.
  • Screw compressors are positive displacement machines that have distinct working phases: suction, compression and discharge. Two counter-rotating helical screws are arranged in a compressor casing; gas inlet and discharge nozzles are at opposite ends.


Dynamic compressors work at a constant pressure but their performance is affected by external conditions, such as changes in inlet temperatures. Air is drawn between the blades on a rapidly rotating compression impeller as it accelerates to a high velocity. The gas is then discharged through a diffuser, where the kinetic energy is transformed into static pressure. These compressors are designed for large volume flow rates. Depending on the main direction of the gas flow, they are called radial or axial compressors.

  • Axial flow compressors use multiple vanes to increase the compression capabilities of a machine. They are often used in high-volume situations where a single rotary vane is not sufficient. They have a high-efficiency rate but are more expensive than other types of compressors. 
  • Centrifugal compressors slow and cool incoming air through a diffuser in order to build up potential energy. Because of their multi-phase compression process, they’re able to produce a high amount of energy in a relatively small machine. They require less maintenance than reciprocating compressors and some types can produce oil-free air.


Which hydraulic compressor is right for my application?

The selection of compressor technology depends on the application. The rule of thumb: dynamic compression technology is best suited for baseload requirements, while positive displacement compression is better suited to variable load. For larger flows and variable demand applications, a combination of both technologies helps to reach the optimal usage of compressed air while simultaneously reducing energy consumption. You’ll also need to  consider the initial purchase price, ease of and cost of maintenance, size, availability, airflow and longevity. 

Gaspro offers low cost, low maintenance hydraulic driven compressor units for low volume and high differential pressure applications; reciprocating compressors (single-stage and two-stage) and rotary vane compressors. This equipment captures gas at a low flow rate, eliminating the need for venting or flaring and improving well economics and efficiency. Gaspro Compression Corp has a focused team that takes pride in their work. We strive to provide dependable products and prompt service to all clients. We’re continually improving and innovating our products to meet changing industry demands. Gaspro is a leading provider of compressor packages in Canada. Contact us to request a proposal.