There are many different turbochargers on the market in diesel and gasoline engines across a wide range of applications and industries. While all turbochargers are different in size, shape, and configuration, they all work the same and share essential parts. The turbo in a jet engine will work basically the same as the turbocharger in a car. In this article, you will become more familiar with the anatomy of a turbocharger and how each part works.
The Turbocharger
At the most basic level, a turbocharger consists of three essential parts: the turbine, the compressor, and the bearing system that supports the turbine shaft, connecting the compressor and turbine wheels together. Understanding how the three components work together is crucial. Even a basic understanding of the relationship of the components to one another will make selecting turbo parts or a turbocharger easier.
Compressor Housing
The compressor housing is where clean air is gathered and compressed before being forced into the engine. It houses the compressor wheel. This is usually manufactured from aluminum on modern turbochargers and typically features a “volute” or spiral-shaped design, which helps to provide optimum airflow and air pressure to the engine.
Compressor Wheel
Sitting inside the compression housing, it is usually manufactured from lightweight aluminum. The compressor wheel spins at a high rate and pulls in the air before compressing and pressurizing it. This air is then forced through the spiral compressor housing and into the engine.
Compressor Piston Ring
This circular piston ring provides a flexible seal between the thrust collar and the backplate of the turbocharger. It’s a small but vital component of the turbocharger that provides oil control and prevents contaminants from getting into the gearing system from the compressor.
Backplate
Also known as the seal plate, this plate connects the bearing housing to the compressor housing. It acts as a retaining device for the thrust bearing system. The backplate serves as a sealed barrier, which prevents compressed air from entering the bearing housing.
Bearing Housing
The bearing housing holds the thrust bearing and journal bearings. It provides them with the oiling circuits so that they can operate freely. In some turbochargers, the bearing housing also houses a water-cooling system. Bearing housings are typically manufactured from heavy cast iron.
Thrust Bearing
The thrust bearing is located inside the bearing housing. It controls axial movement (in and out movement) in the turbine shaft between the compressor and turbine wheels. Because the turbine and compressor wheels rotate at high speeds, the thrust bearings need to be lubricated with oil to eliminate friction and prevent wear.
Journal Bearing
The journal bearings are located in the bearing housing as well. They control the radial load. In reality, this means that it is their job to ensure that the rotating parts of the turbo (the turbine wheel, the shaft, and the compressor wheel) are both supported and able to spin freely without wobbling up and down too much. Journal bearings are held in place with bearing clips.
Heat Shield
This is located at the back of the bearing housing in-between the bearing house and the back of the turbine wheel. It protects the turbocharger parts from the heat of the exhaust gases running through the exhaust housing.
Turbine Housing
Typically made from cast iron or a high-temperature alloy, the turbine housing collects gases from the engine, funneling them towards the turbine wheel to rotate. Like the compressor housing, it features a “volute” spiral design to help maximize the speed of the exhaust gases running through it.
Turbine Wheel
The turbine wheel is used to help transform the energy from an engine’s exhaust gases into kinetic energy, which is then used to drive the compression wheel. Because turbine wheels generate a lot of heat, they are generally manufactured from lightweight, durable, and heat-resistant alloys.
Turbine Piston Ring
This ring provides a seal between the bearing house and the turbine wheel. It has two purposes. The two functions prevent oil from getting into the turbine housing and protecting exhaust gas from getting into the bearing housing.
Shaft Nut
The shaft nut keeps the compressor wheel and the thrust collar attached to a turbine shaft as they all rotate.
The Wastegate Actuator
The wastegate actuator is a valve that diverts exhaust gases away from the turbine wheel. This helps to control the speed of the turbine and prevents it from over-speeding, regulating the speed of the compressor and the boost pressure. This protects from unnecessary wear on the turbocharger by capping the maximum boost pressure of the turbo at a safe level.
Rotating Assembly
When the turbine wheel, thrust collar assembly, compressor wheel, and shaft nut are all connected, they are known as the rotating assembly. It’s important to remember that these components work together. Replacing one element of the assembly can have a chain-link effect on the other parts. They often have to be replaced together.
Bypass Valve
Also known as the blow-off valve, the bypass valves are a pressure release system designed to prevent turbo compressor surge. It also helps reduce wear on both the turbocharger and on the engine itself when changing speeds. Compressed air escapes from the turbo into the atmosphere or by redirecting this air back into the air intake when the RPM of the engine changes.
Where Can I Get Quality Turbocharger Parts?
TurboTurbos has been in business for twenty years and is waiting to answer any questions you may have about turbochargers. Over the years, we have worked closely with the industry’s top manufacturers. We have new and used turbo for sale, as well as turbocharger parts for a wide variety of vehicle types to guarantee you get the parts you need.
We thank you for taking the time to read more about the anatomy of a turbocharger and how each part works. We have the turbocharger replacement parts you need to get your vehicle up and running again. All our parts are exact, direct-fit turbocharger parts. Contact our team today if you have any questions about our products, or if don’t see the item you are looking for.