Posted to News on 23rd Aug 2009, 15:53
Tough, high-performance bearings for mining machinery
NSK has worked with global manufacturers of mining machinery to develop a package of tough, high-performance bearings that offer longer service life under demanding mining conditions. A new free publication detailing these products is available on request. This bearing range is designed to cope with the dust, mud, high loads and extreme temperatures that are encountered in mining and extraction environments. It is claimed to exceed the limits of conventional bearings both in terms of longer operating life and limiting speeds, thereby helping to deliver the high levels of reliability required in mining projects all over the world.
Developed specifically for applications with heavy or shock loads, such as those encountered in jaw and cone crushers, NSK's CA series of double-row spherical roller bearings are manufactured with a machined brass cage to combat the effects of vibration, operating fatigue, wear and corrosion. The CA bearings have high load rating, superior durability and are resistant to wear.
Extending the CA range into harsh vibrating applications is NSK's CA-VS series of spherical roller bearings. VS series bearings have been optimised for use in harsh vibrating applications. Their vibratory specification builds upon the extended load and life benefits of the standard CA construction with an optimised design that provides improved fatigue strength against the vibration and shock loads conditions encountered on screens, feeders and compactors.
Reduced maintenance and energy costs
In addition to addressing the problems of heavy shock loading and vibration, NSK is also providing significant benefits to mining and extraction industries by reducing maintenance and energy costs and enabling product downsizing. The new bearing range that provides these benefits is the HPS series of spherical roller bearings. HPS bearings offer innovative performance with twice the running life of conventional SRBs of the same size, and a maximum limiting running speed that has been improved by up to 20 per cent.
Also providing improved performance benefits, this time as a result of extra rollers in their design, is NSK's EW/EM series of cylindrical roller bearings. These bearings are used in applications such as: the differentials of off-road trucks; the transmissions and torque converters of crawler dozers; the transmissions of wheel loaders; and the speed reducers and hydraulic pumps used on hydraulic excavators.
The EW/EM series CRBs are capable of carrying particularly large radial loads and are also suitable for high-speed applications. The EW series features a pressed steel cage, and the EM series a one-piece machined brass cage. Both of these designs offer high load ratings for standard size bearings, in addition to excellent and longer operating life - approximately twice that of conventional CRBs.
Other applications
Additional equipment areas that are also benefiting from improved reliability and longer operating life as a result of NSK's bearing development programme for mining are conveyors, feeders and general handling equipment, crane sheeves and mobile gantries. NSK's plummer block ball bearing units are used widely in mining and minerals extraction - on conveyors, feeders and general handling equipment - due to their tough construction and time-saving, easy installation and mounting benefits. NSK has built-upon the robustness of these bearings with a design that includes high-efficiency, steel-reinforced seals and cast iron bearing covers for added protection.
Also benefiting from NSK's focus on improving bearing life in mining and extraction applications is a new range of full-complement cylindrical roller bearings for use in crane sheeves. These bearings offer advanced levels of ingress protection with a new sealing system that minimises grease leakage and increases resistance to the entry of water and other contaminants.
Designed to provide maximum reliability and operating life in the difficult environments encountered in mines, quarries, ports and building sites, the new full complement bearings are supplied with phosphate surface treatment to improve their resistance to corrosion.
The ability of the bearings to provide reliable life in arduous environments is also enhanced by specially machined holes on the inner and outer rings of the bearings to allow grease replenishment, even with the bearing in situ.
NSK has detailed its innovative bearing products for mining machinery in a new FREE publication. Running to 34 pages, the booklet provides a wealth of information regarding the choice of bearings for machinery used in the mining and extraction industries. Copies of the publication are available by telephoning NSK's marketing department on +44 (0)1636 605123.
