The Mechanics of a Diesel-Powered Air Compressor: How Does It Work?

Jun 22, 2022 | Air

If you’ve always wanted to know how diesel-powered air compressor work, specifically the ins and outs of operating these magnificent devices and the benefits of doing so, read on.

Large and small machinery—everything from drills to nail guns, grinders, spray guns, sanders and even staplers—are commonly used with air compressors. We relied on complicated systems of belts and wheels before contemporary air compressors arrived on the scene.

Today, they can be found everywhere, from little pneumatic tools in most people’s garages to massive machinery in industries. Also, do you require a diesel generator for your construction site? Viking Industrial offers Kubota Diesel Generator which provides exceptional dependability and service life.

The fact that each tool does not require its own heavy engine is a significant advantage of airpower. The electrical energy is instead converted into kinetic energy by a single motor on the compressor. This results in tools that are light, compact, easy to use, run silently and have fewer parts that wear out.

You’ve come to the right place if you want to learn how different air compressors work and how they may help you in your daily life—keep reading to find out everything you need to know.

Diesel-Powered Air Compressor

Anatomy of air compressor powered by diesel

Simply put, air compressors do exactly what they sound like they do—they employ air pressure to accomplish their goals.

To begin, they compress air into a smaller volume than it was previously. Following this, the newly compressed air is pumped into a storage tank. The air compressor turns off when the tank reaches its maximum pressure, and you can use the compressed air inside.

Regardless of size or application, the components found inside air compressors are usually relatively similar. The following are some of the most prevalent parts:

  • An engine
  • An inlet valve
  • An outlet valve
  • A pump for air compression
  • A storage tank
  • A primary oil separator tank.

While not all compressors include storage tanks, the majority of bigger types do. As a result, unless a model is extremely portable, it makes sense to have a storage tank.

How do air compressors powered by diesel work?

An air compressor operates primarily on the principle of air displacement. Simply put, when air is forced into a compression chamber, it gets compressed. Positive and dynamic displacement are two types of displacement.

Positive displacement

This is the most widely utilised method, and it is critical to grasp in engineering. Positive displacement compressors suck air into a chamber and reduce the capacity of the chamber to compress the air.

Dynamic displacement

This approach simply entails the introduction of air into a chamber via revolving blades. The movement of the blades rapidly builds pressure in a chamber and produces massive amounts of compressed air. Centrifugal Force compressors and Axial Compressors are the two main forms of dynamic displacement compressors.

Diesel air compressor types

Below, we look at three different types of air compressors.

Screw compressors (rotary)

Rotary screw compressors are typically used in industrial applications and are available in a number of sizes. Inside the electric motor, two screws rotate in opposite directions. In rotary screw air compressors, this motion creates a vacuum that pulls air in. The air drawn into the threads of the rotary screws is squeezed and then released through the exit valve.

Compressors with pistons (also known as reciprocating piston compressors)

When the piston of a reciprocating air compressor moves, it compresses the entering atmospheric air. An intake valve (also known as a suction valve) allows air to enter the cylinder. A storage tank for compressed air is generally included with a piston compressor, which minimises wear and enhances efficiency.

The majority of diesel-powered air compressors are piston-driven and come as self-contained units with the engine and compressor located next to each other.

Rotary (vane) compressors

These use a variety of rotating vanes of various diameters. When the automatically adjusted arms rotate in rotary vane compressors, the air is pulled into the chambers. When the motor spins, the air travels with it, causing the arms to approach the output, narrowing the gap between the vanes and the casing. Compressed air is formed as a result of this process.

Air compression stages

Single-stage compressors

A single-stage cycle is used by the majority of piston-based compressors. This indicates that the engine compresses the air in a single stroke.

Two-stage compressors

In a two-stage cycle, one piston compresses the air before moving it to a smaller chamber, where it is further compressed. When operating, these compressors generate a lot of heat, and the air must be cooled down between cycles.

Aspects of air compressors that should be considered


The pressure flowing out of the exit valve is reduced or increased by regulators. The regulator compresses a spring, which closes a valve and lowers pressure. This is usually done to provide the necessary pressure to operate your air tools.


The portability of the diesel air compressor is one of its strongest points. They’re usually installed on wheels and may be towed by just about any vehicle. They’re designed to work in a variety of temperatures and may be left on for hours or days without issue. Your compressor will keep working as long as you have both oil and diesel.

Availability of a wide range of alternatives

The versatility of portable diesel compressors is another area where they excel. There are a plethora of improvements you may make to your compressor to expand its capabilities, including:

  • Filters at the inlet for excessively dusty incoming air
  • Heaters (to warm air that has been cooled, preventing dampness)
  • Air conditioners (to cool down air once it has been compressed)
  • Adaptors for tow bars
  • Beginning (cold) (to start in extremely cold areas)

Features of safety

There are also a number of safety measures that can be really useful. If you’re going to use your compressor near flammable materials, you should have a spark-arrestor fitting to avoid explosions.

Diesel compressors work in the same way as standard electrical compressors, but with the added benefit of being powered by diesel rather than electricity.

Diesel engines

As previously stated, every compressor comprises a motor that is used to operate the pump. When using an air compressor with a combustion engine, the engine is normally connected directly to the compressor. Some methods connect the diesel engine to a set of pulleys and belts that assist in motor regulation.

A diesel-fueled air compressor will usually have a simple control system, unlike the larger, more complicated stationary ones you may find on a factory floor. The engine is typically controlled mechanically and is linked to the compressor.

It is controlled by a basic start/stop button (and occasionally a load/unload button).

Find the ideal air compressor for you

Understanding how diesel-powered air compressors function, is key to finding the right fit. Check out our range of new and used air compressors, or contact the Viking Industrial team for advice, to find the right one for you.

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