Chain Lubrication is oft-overlooked by the maintenance practitioners; sometimes used-lubricant is applied, and sometimes greases, both highly inappropriate. The use of incorrect lubricants can often cause chain elongation, chain breakages, and jerky, un-smooth motions.
What most end-users miss is that chain lubrication is a pure boundary lubricating condition, wherein high-load, metal-to-metal contact occurs at the pin-roller-bushing interface. Firstly, therefore, is to have a lubricant with creeping or penetrative capabilities to seep into the pin-roller-bushing areas, which is impossible if one uses greases.
Secondly, owing to the boundary friction regime, used-lubricants, perhaps hydraulic oils, do not possess the high viscosities, such as ISO VG 320, and extreme pressure (EP) additives that are ideal for such conditions. Moreover, used lubricants are typically characterized by sludge or carbon, that would in fact clog the entry of oils into the pins, rollers and bushings.
Ideally, chain oils should also contain tackifiers that improve adherence to the metal surface, to prevent drip-offs which would make the working area unsafe, and if the chains are used to convey goods for manufacture, the adhesive chain oils will prevent any unwanted migration or contamination.
Lastly, the tackifier component in the chain lubricant ensures an even uninterrupted film on the chain, preventing the possibility of rust and corrosion on the chain.