Sealed Split Spherical Roller Bearings. When a bearing fails, it usually takes an entire day to remove and replace traditional bearings in the trapped positions on the shaft and to realign the driveline. This results in a full day of plant downtime, plus the costs associated with lost production, replacement parts, and resources being diverted from other tasks to handle the repair.
SKF offers a solution with the SKF Cooper sealed split spherical roller bearing (SRB). “The innovative design of this robust bearing allows for safe, time-saving replacement of bearings in the trapped position,” says sales engineer, Duncan Mngomezulu. “Since there’s no need to dismount the drive coupling or the cantilevered drive during replacement, shaft alignment and the driveline experience minimal disruption, thereby avoiding the need for time-consuming realignment.”
Mngomezulu highlights the numerous benefits of in-situ bearing replacement. “Firstly, mean time to repair (MTTR) can be reduced by up to 70%. To put this into perspective, a repair time of 12 hours can be shortened to just 3.5 hours. Furthermore, considering that, on average, 43% of accidents in the mining and cement industry occur during maintenance or checks on conveyors, shorter repair periods significantly reduce safety risks. In essence, simplifying maintenance enhances safety.”
SKF Cooper sealed split spherical roller bearings are designed to meet the high demands of industries with heavy-duty operations such as mining, mineral processing, cement, pulp and paper, metals, power generation, and food and beverage. These industries benefit from improved bearing reliability, increased machine performance, and enhanced safety, leading to optimized operations and sustainable production. This bearing solution serves a variety of equipment, including conveyor pulleys, bucket elevators, escalators, mixers, agitators, and horizontal grinding mill pinions.
SKF Cooper split spherical roller bearings are manufactured to ISO Normal precision and running accuracy. The split bearing outer ring has the same external dimensions as a standard ISO spherical bearing outer ring. SKF Cooper sealed split SRB is compatible with SKF metric and inch split block housings such as SNLD, SMS, and SAF/SDAF.
The wire-cut inner and outer ring manufacturing technique and sealing of the SKF Cooper split bearings ensure a longer service life (MTBF) compared to other split bearings. The steel inner ring clamping rings allow the SKF Cooper split bearings to sustain higher axial loading than other forms of split bearing and ensure better clamping against axial movement. Although the maximum permissible axial loading is generally lower than that of a non-split spherical roller bearing mounted on an adaptor sleeve, SKF advises checking it against application requirements. The design of the SKF Cooper bearing reduces the risk of shaft fretting.
The SKF Cooper bearing uses ISO 281:2007 to calculate the L10m modified rating life of the split spherical roller bearing. Incorporation of bearing sealing as standard typically doubles the rating life compared to open unsealed bearings because of improved contamination exclusion. The sealed solutions on the SKF Cooper sealed split SRBs, available as standard, increase protection against contamination and reduce maintenance needs. The seals function effectively in ambient temperatures ranging from -40 to 90°C.
“We recommend ensuring adequate lubrication for normal operating conditions,” advises Mngomezulu. “SKF Cooper bearing components are heat stable up to 120°C during continuous operation, with recommended use of ISO VG 220 oil or ISO VG 320 oil as required.”
In conclusion, Mngomezulu confirms that many customers worldwide report significant time and cost savings after replacing traditional bearings with SKF Cooper sealed split bearings. “A notable success story comes from a coal mine in the USA. By replacing traditional bearings with SKF Cooper bearings on the conveyor head pulleys that operate around 18 hours per day, the mine saved over 10 hours of downtime and avoided over a hundred thousand dollars in lost production.”