A manufacturer of frozen pizzas was experiencing failures every four weeks on the belt tensioner serving one of its food conveyors. However, a simple change to NSK moulded-oil bearings resulted in significantly prolonged operating life, leading to annual cost savings of €15,360.
Within the framework of NSK’s AIP programme (Added Value Programme), which is offered as a service to bearing users, company experts inspected the failed bearings and performed an application review at the frozen pizza plant. The team determined that the damage was mainly due to frequent cleaning of the production line using water. This process was causing damage to the bearing seals, as well as corrosion of the rolling elements and raceways. Moreover, lubricant was being washed out of the bearings due to water penetration.
To remedy the situation, NSK recommended replacing the existing standard bearings with Moulded-Oil bearings made of stainless steel. NSK’s Moulded-Oil bearings are ideal for applications in food plants. Not only do they prevent the ingress of contaminants such as water and particulates, but no lubricant can escape the bearing and enter other parts of the machine, where it could potentially contact food.
Moulded-Oil bearings are equipped with a proprietary oil-impregnated material that consists of lubricating oil and a polyolefin resin with an affinity for oil. This carrier material releases the lubricant continuously over a long period. The operating environment is therefore kept clean as no grease is released and no oil refilling is needed.
As a rule of thumb, in applications where the operating environment is moist and dust-contaminated, the service life of Moulded-Oil bearings is more than twice that of bearings with conventional grease lubrication.
After the bearings were installed at the pizza plant, there were no more failures for a whole year. In the cost analysis for the upgrade, the only cost item was the one-time investment in Moulded-Oil bearings. As a result, the previous costs associated with bearing replacement, maintenance and lubrication have been eliminated, providing the plant with annual savings moving forward of €15,360.