Rotary Coal Valve

A customer experienced serious recurring failures three times a year on a bearing fitted to a rotary coal valve at an ore preparation plant. NSK engineers determined the existing bearing design was inadequate for the high temperatures involved and recommended an RHP HLT bearing insert inside a Self-Lube cast iron FC housing, together with a ring made of heat-resistant material and an NSK adapter plate. The installed bearing units ran without failure for 12 months and the need for compressed air cooling was eliminated.

• Rotary coal valve — coal dust; 1 machine, approx. 4 months service life
• Bearing overheating; incorrect lubrication quantity and frequency
• NSK solution: RHP HLT bearing insert in Self-Lube cast iron FC housing + NSK adapter with heat-resistant ring
• Changes to lubrication quantity and frequency recommended
• No bearing failure for 12 months
• Annual compressed air cost (€88,954) eliminated entirely

Technical Features: RHP HLT Self-Lube Bearing Unit

• Special internal geometry; C5 internal clearance (helps prevent radial preload)
• High-performance Klueber grease
• Durable silicone rubber seals
• Steel cage material
• Interchangeable with standard Self-Lube inserts
• Effective lubrication, sealing and protection between −40°C and +180°C
• Special construction designed to operate at extreme temperatures