The following methods have proven useful for monitoring the lubrication condition in steel chains:
– Direct inspection of the chain pins: This involves stopping your machinery and disassembling the chain. Sufficient lubricant supply is indicated by an oil film that fully coats the chain pins and shows no discolouration. The loaded side of the bolt should be completely smooth and no tempering colour should be visible on link components. Both the chain links and the rollers should move without effort. Note: tempering colour is the result of excessive temperatures in the chain link, while oil discolouration is caused by abrasion and cracking.
– Indirect inspection by monitoring the power consumption of the drive motor: This method makes sense only in continuous processes with constant driving power. Its advantage is that it can be performed during operation. Lubricant starvation allows friction to increase and consequently leads to power loss. The motor then has to compensate for this loss by consuming more power.
– Indirect inspection by monitoring the noise generated by the chain: Properly lubricated chains with low wear produce fairly little noise. This damping effect depends on a sufficient amount of lubricant.