Roulements - 06/08/2009
NSK engineers visited the frozen food plant to view the application and obtain samples of the failed bearings for inspection and analysis. The subsequent report, compiled by NSK, confirmed that the main cause of failure was the excessive temperature the bearings had been subjected to. In view of this, NSK suggested that its HLT Self-Lube® inserts would be more suited for the application.
HLT Self-Lube® inserts provide opportunities to reduce maintenance, downtime and replacement costs at temperatures as high as + 180o C (and as low as - 40oC). With a greater than standard internal clearance, the HLT inserts are especially suited to high temperature applications; the increased clearance between the balls and raceways helps to prevent radial pre-load - even at + 180oC; thus maximizing bearing life.
The provision of pressed steel cages to ensure reliable performance at extremes of temperature is another feature of the HLT design; as is Silicone rubber seals. The seals have a wide operating temperature range and flexibility at high and low temperatures.
Finally, to ensure long term operation in both high and low temperature applications an especially pure, high performance grease is used on the bearings.
HLT inserts are available across the entire Self-Lube® range, which includes pillow block housings, flange units, cartridge units and hanger units. They offer a relubrication facility, as standard, and the facility for fitting the patented Self-Lube® Protector, on pillow block types.
The effectiveness of the change to HLT bearing inserts at the frozen food plant is evidenced by the fact that in the 18 - months since they were first installed, there have been no unplanned bearings changes, saving the manufacturer £5,984 per year in bearing, downtime and lost production costs.