Renew as needed

NSK is currently developing a high-precision method for quickly and accurately diagnosing the remaining service life of lubricant in rolling bearings and linear units. This solution will be available as a mobile app that allows users to determine the condition of the lubricant on site. This reduces the need for external analyzes and the lubricant can be renewed as needed. NSK thus supports users in implementing condition-based maintenance strategies.

Grease-lubricated drive elements such as rolling bearings, ball screws and linear guides are used in a wide range of machines, systems and vehicles - from machine tools to rail vehicles. However, as the lubricant degrades or changes properties over time, on-site inspection is important to maximize uptime and OEE (overall equipment effectiveness). In recent years, many companies have changed their maintenance strategy from “time-based” to “condition-based”. It would be helpful to have a method for diagnosing the condition of the lubricant that can be used quickly and with high accuracy on site - ideally as an app. Such an app would also make sense given the shortage of skilled workers, and it would support efforts to make maintenance as CO2-neutral as possible.

A laboratory analysis is currently required for precise diagnosis of the lubricant condition, but this is associated with high costs and a long waiting time for the result and cannot be carried out completely on site. In practice, visual assessment or a measurement with a densitometer are therefore more common. However, both methods are not very accurate. This is why many companies top up lubricant unnecessarily early to ensure stable machine operation. The consequences are waste of resources and unnecessary costs.

Against this background - and on the basis of the extensive expertise in tribology, which has been documented, among other things, in the formulation of its own lubricants for more than forty years - NSK developed a much more convenient, cost-effective, faster and more precise method for diagnosing lubricants. With the new NSK app, the user can analyze the degree of lubricant wear based on a small grease sample.

Here's how the process works: Chemical changes to a grease's base oil and additives are caused over time by heat and oxidation. This changes the molecular structure of the lubricant - with the result that more short-wave light is absorbed. This has visible effects because the color of the fat changes. Initially it is white, over time it turns yellow or orange and finally black - then it has reached the end of its lifespan. The diagnostic app developed by NSK qualifies the grease based on its color to calculate the remaining life and displays the result. The user therefore knows – in the sense of condition monitoring – very precisely whether lubricant needs to be refilled or not.