When you're driving a regular car, it's easy enough to get your daily transport to a garage that provides oil changes. But if you're operating a 55-ton (50-metric-ton) wheel loader, it's a little bit more difficult to cruise down to the local service station.
For vehicles of this size, it makes more sense to change the oil at the work site. And portable centrifugal oil cleaners are the perfect solution. The centrifuge is mounted to a cart or trolley, which maintenance personnel can move from one piece of equipment to the next.
The great thing about portable centrifugal cleaners is that they can do their work while the vehicle or machine continues to run. In this way, they function a bit like a heart/lung machine used during open-heart surgery. An input line carries oil from the vehicle to the centrifuge, where it is cleaned and filtered. Then an output line delivers clean fluid back to the vehicle.
The heart of the system is the centrifuge, so let's take a closer at its three main parts:
Body: The aluminum body, which houses the rotor and the drive chamber, allows the whole system to be mounted to an external structure, either an engine, cart or trolley. Dirty oil enters the centrifuge through an inlet at the base of the body. Oil travels up through a hollow spindle until it encounters a baffle at the top. The baffle distributes the oil uniformly into the centrifuge rotor.
Rotor: The rotor does the real business of cleaning. Oil pressure within the rotor causes the assembly to rotate within the outer body at speeds between 6,000 and 7,500 rpm. This in turn creates a centrifugal force that is 2,500 times greater than gravity. Under the influence of such a strong force, particles down to one-tenth of a micron move radially toward the wall of the rotor, where they form a dense cake. In some models, the dirty rotor is simply replaced with a new one; in other models, the rotor is cleaned and reused.
Drive Chamber: Clean oil exits the rotor and enters the drive chamber through two opposing jets, creating the propulsive force that drives the rotor. Eventually, the oil exits the centrifuge at the base and returns to the engine.
The result: Oil that's almost as good as new, which, as we'll see in the next section, is better for the vehicle, the company that owns it and the environment.