Speeding up bearing replacement

An innovative time-saving solution aims to simplify the removal and replacement of bearings in a trapped position on a shaft and eliminate the need for realignment of the driveline. This process usually requires a full day of costly plant downtime, leading to loss of production and the use of valuable resources.

SKF’s Cooper sealed split spherical roller bearing (SRB) enables bearing replacement without needing to dismount the drive coupling or the cantilevered drive. This means there is minimal disturbance to the shaft alignment or driveline, subsequently avoiding timeous realignment.

SKF South Africa territory sales engineer: Eastern Limpopo/ Mpumalanga/Eswatini Duncan Mngomezulu explains that in-situ bearing replacement can reduce the mean time to repair by as much as 70%, while shorter periods of exposure to the repair site also significantly reduce safety risks.

The sealed split SRBs are designed to meet the demands of industries running heavy-duty operations such as mining, mineral processing, cement, pulp and paper, metals, power generation and food and beverage. Improved bearing reliability helps to increase machine performance and enhance safety for optimised operations and sustainable production. The bearing solution serves a range of equipment including conveyor pulleys, bucket elevators, escalators, mixers and agitators, and horizontal grinding mill pinions.

SKF Cooper split SRBs are manufactured to ISO Normal precision and running accuracy. The split bearing outer ring has the same external dimension as a standard ISO spherical bearing outer ring and the 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 are designed to ensure longer service life compared to other split bearings. The steel inner ring clamping rings permit the bearings to sustain higher axial loading than other forms of split bearings and ensure better clamping against axial movement. As the maximum permissible axial loading is not generally as high as a non-split spherical roller bearing mounted on an adapter sleeve, SKF advises that it should be checked against application requirements. The design of the SKF Cooper bearing is said to reduce the risk of shaft fretting.

The SKF Cooper bearing uses ISO 281:2007 to calculate the L10m modified rating life of the split SRB. The incorporation of bearing sealing as standard helps to increase the rating life compared to open, or unsealed, bearings because of the increased protection against contamination. The seals have a limit of – 40 °C to 90 °C ambient temperatures. 

“We recommend that the bearing is checked for adequate lubrication for normal operating conditions,” advises Mngomezulu. “SKF Cooper bearing components are heat stable up to 120 °C at continuous operation with recommended use of ISO VG 220 oil or ISO VG 320 oil as required,” adds Mngomezulu.

Wrapping up, Mngomezulu affirms that countless customers around the globe report tremendous time and monetary savings after replacing their tradition bearings with a SKF Cooper sealed split bearing. “A noteworthy success story is a coal mine in the USA that, by replacing their traditional bearings with SKF Cooper bearings on their conveyor head pulleys that operate around 18 hours per day, saved over 10 hours of downtime and avoided over $100 000 in lost production!”