Friction and Energy Efficiency

Tribological Investigations in Drive Systems

In the iwis drive systems testing laboratory, a tribometer is used to perform friction and energy efficiency analyses on chain components. The aim of these investigations is to determine the coefficient of friction between various components of a chain drive and thereby improve the overall efficiency of the application.

What is friction – and why does it occur?

Friction occurs between two bodies or objects that are in contact. It is mainly caused by irregularities on the surfaces. Friction generates what is known as the frictional force. This force depends on two factors: the coefficient of friction and the normal force. The normal force acts perpendicular to the frictional force — and a higher normal force results in a higher frictional force.

As soon as two bodies move relative to each other, frictional losses occur: these are reflected as heat in the component or the system.

Where does friction occur in the example of the accumulation conveyor chain?

Friction within the chain occurs between the pins, the bushings, and the support or accumulation rollers. By the way: friction is not always undesirable. The accumulation roller carries the workpiece carrier — frictional force is necessary to accelerate the workpiece carrier. Therefore, the rule is: as much friction as necessary, but as little as possible.

Frictional losses occur in the following components of the chain drive: chain, chain tensioner, chain guide, sprocket, workpiece carrier, and conveyed goods.

Typical influencing factors on the coefficient of friction

Material of the components
Surface condition
Coatings
Lubrication and temperature
Type of motion (rotating or oscillating)
Process dirt and particles

Analysis of Energy Consumption Reduction

Our experts in the testing department are happy to assist you with the analysis of your system’s energy consumption. A key factor for improving efficiency lies in the proper installation of the chain: by correctly aligning the sprockets and guides, as well as ensuring optimal chain tension, you can make sure that no unnecessary energy is wasted during operation.

Incorrect assembly, on the other hand, can lead to axial or angular misalignment — resulting in increased friction between the plates and the sprocket or guide. This, in turn, increases the chain tension force, causing additional frictional losses, higher wear, and ultimately greater energy consumption.

Lubrication and maintenance also play a central role in energy efficiency. Insufficient or missing lubrication not only leads to higher frictional resistance and power consumption but also increases noise levels and significantly accelerates wear..

To counteract this, the lubricant must penetrate specifically into the chain joint or the friction contact — prior cleaning may be necessary. The difference is significant: in the dry state, the coefficient of friction is approximately 400% higher than with optimal lubrication.

Where re-lubrication is not possible, we recommend the use of maintenance-free MEGAlife chains. Alternatively, brush systems or CLA system can be used to continuously and appropriately supply the chain with lubricant as needed.