How to select the best chain lubricant for the application.

Chain drives have long been accepted as amongst the most efficient, but have always suffered from being exposed to harsh operating conditions which in turn have made to job of the chain lubricant almost impossible. This makes selecting the correct chain lubricant vital to life of the chain.

The almost impossible task of delivering chain lubricant to the right place!

The objective with chain lubrication
is to place a small quantity of lubricant between the pin and the barrel in each link. Because it is impossible to directly inject the lubricant to the correct locations, practitioners try other methods, including running the chain through a bath, spraying, pouring and painting lubricant on the chain's outer surfaces.

For slowly turning chains, the oil bath is a practical, useful approach. Some attention is required to maintain an appropriate sump level and clean any excess lubricant off machine surfaces.

What chain lubricant should be used?

Chains tend to be lubricated with whatever is handy.

Slowly turning, heavily loaded industrial application chains require a heavy oil. Medium gear or heavy circulation oils are common choices.

For intermittent re-lubrication, any chain lubricant coating on the exterior of the chain creates an opportunity for airborne debris to build up and choke off oil flow to the internal components, where it’s really needed.

In addition, depending on the hardness of the airborne contaminant, this wetted material may act like a grinding compound working against the sprocket and barrel of the chain.

These roller chain applications (Such as motorcycle chains) are good candidates for chain lubricant with solid film additives mixed with a light, evaporating carrier. The light oil penetrates, carrying the solid additives to the contact point where it’s needed. The solid additives remain behind to provide a “dry film” protection after the carrier has been displaced. The exterior of the chain also does not accumulate as much atmospheric contaminant.

A chain lubricant should have low enough viscosity to penetrate into critical internal surfaces and high enough viscosity, or necessary additives, to maintain an effective film at the prevailing temperature and pressure. The chain lubricant should also have the capability to maintain the desired lubricating qualities under prevailing operating conditions, and be clean and free of corrosives.

In selecting the correct chain lubricant, a good grade of nondetergent petroleum base oil is usually less important. While detergents are not normally needed, anti-foaming, antioxidizing and extreme pressure additives are important. Impure oils should be avoided. Acids or abrasives in the oil can permanently damage the chain.

The chain manufacturer often uses grease or petroleum jelly as an initial chain lubricant. However, users generally should not apply greases to chains in service because they are too thick to penetrate into the internal bearing surfaces of the chain.

To sum up: When selecting the correct chain lubricant it’s important to consider the operating environment, the load and speed and accessibility to re-lubricate frequently.

Consult the experts at Habot Synthetic Lubricants to assist you in selecting the correct chain lubricant for your specific application