Bearing applications in construction equipment

Bearings manufacturer Schaeffler has been working closely with construction vehicle and equipment manufacturers for many years. By getting involved early in the design process, Schaeffler's engineers have helped construction equipment makers develop more innovative, efficient and cost effective bearing arrangements.

One area where construction vehicles can help the environment is through eliminating the use of lubricants. Engineers at Schaeffler have developed Elgoglide, a range of maintenance-free bearings that require no lubrication.

Schaeffler's ELGES bearings are coated with a sliding surface based on Teflon fabric. They therefore require no additional lubricant supply; the PTFE in the slideway lining ensures functional reliability and enables maintenance-free operation for the life of the part. Oscillating motion, such as the frequent swivelling motion present in construction equipment, is endured due to the solid and moisture-resistant combination of the sliding layer and the steel support body. Overall, the customer receives a bearing that offers a well-balanced combination of high load capacity, excellent wear and frictional behaviour, as well as outstanding dry running characteristics.

Easy-to-mount bearings

The maintenance work and time-consuming mounting operations involved in installing bearings in construction equipment and vehicles interrupts construction work unnecessarily. For this reason, Schaeffler has developed a range of ready-to-mount bearing support systems that incorporate Elgoglide high-performance plain bearings.

These bearings are easy to mount, with all components - pins, tensioning system and plain bearings - fitting together perfectly. The units are pressed into housings and frames and require no additional axial location. Implementing the appropriate surface treatment considerably reduces the formation of rust on exposed bearing components.

For wire rope sheaves in mobile cranes, Schaeffler's range of INA SLO4..RR, full-complement cylindrical roller bearings are designed to withstand high loads. Lip seals, special grease and Schaeffler's rust-resistant surface coating, Corrotect, offer highly effective protection from contamination and water splash. The bearings are easy to mount in wire rope sheaves; due to annular grooves, the outer rings are simply located with retaining rings.

Schaeffler's four-point contact ball bearings and ELGES spherical plain bearings are used to support articulation joints on construction vehicles. This combination offers a rugged, compact design for torsional and steering motion. The four-point contact ball bearing has a high load rating, is very stiff and easy to mount. With its clearance-free, preloaded raceway, this bearing is more than a match for the requirements of these applications.

The maintenance-free ELGES bearings are designed for high shock loads and alternating loads. Contact pressure is up to 300N/mm2 (dynamic), or 500N/mm2 (static). Schaeffler offers radial, thrust and angular-contact spherical plain bearing types, all with excellent load-to-weight performance ratios.

Premium-quality X-life bearings

Schaeffler also provides standard and custom-designed bearings for manufacturers of vertical crushers and for vibrators in vibratory compacting equipment and sheet pile drivers. These bearings must withstand high shock loads and radial acceleration in a small space. Misaligned bearings and shaft deflections put extra strain on the bearings, and ambient conditions are often unfavourable.

In many cases, because conventional cylindrical bearings cannot meet these high requirements, Schaeffler offers customers its premium-grade X-life range of bearings. Take Schaeffler's FAG single-row cylindrical roller bearings (NJ) with brass cages, for example. The X-life version of this bearing delivers 18 per cent higher load carrying capacity, which increases the basic rating life of the bearing by more than 70 per cent.

In addition, Schaeffler's LSL (with disk cage) and ZSL (with plastic spacers) range of low-friction, cylindrical roller bearings are suitable for demanding requirements in terms of dynamics load carrying capacity. In vibratory compactors, for example, the bearing speeds can reach 2500rpm and accelerations of up to 500m/s2.

For more information on Schaeffler's range of bearings for construction vehicles and machinery, visit www.schaeffler.co.uk.