A matching bore, outside diameter and width are only the start. Give the supplier an application brief and approve the complete designation, interfaces, lubricant and operating requirements before ordering a replacement.
Document the duty before requesting a quote
SKF's rolling-bearing catalogue treats bearing size, load, speed, operating temperature and lubrication as interdependent. A selection therefore needs operating information as well as the available installation space.
Our recommended application brief starts with the shaft and housing drawing, available dimensions and existing complete bearing designation. Add radial and axial loads, their direction and variation, speed range, start-stop behaviour, operating temperature, surrounding contamination and required service duty. State which values are measured and which are estimates. Ask the supplier to identify missing inputs rather than silently choosing assumptions.
Sources and further reading: SKF
Approve the interfaces and complete configuration
SKF's selection checklist includes shaft and housing fits, clearance class, cage, precision, seals, mounting and maintenance. Schaeffler likewise stresses assessing the bearing arrangement as a system, including dimensions, load ratings, speeds and operating conditions.
For a replacement, request a comparison of the original and proposed complete designations. Review fits, installed clearance or preload, sealing, cage and relevant temperature limits against the application. Have the responsible engineer resolve differences before release. A catalogue dimension match is not a documented interchangeability decision.
- Record the drawing revision and the exact manufacturer designation, including suffixes.
- Ask for the current manufacturer's data sheet and its explanation of each configuration option.
- Document substitutions, unresolved assumptions and the person authorising the change.
- Confirm the mounting and removal method with the equipment's service instructions.
Sources and further reading: SKF Evolution · Schaeffler Training Campus
Choose lubrication with the working conditions
SKF explains that lubricant choice depends on operating conditions, temperature, speed and the surroundings. Its guidance also distinguishes bearings supplied with integral seals or shields from arrangements that need a replenishment plan.
In the purchase brief, specify the required lubricant or ask for an application-specific recommendation. Record compatibility with the existing lubrication system, contamination control, servicing access and the manufacturer's maintenance method. Do not copy a grease quantity or interval from another machine because its bearing dimensions look similar. Follow the selected product's instructions and confirm uncertainty with application engineering.
Sources and further reading: SKF
Release an order that receiving staff can verify
Our practical release checklist ties the approved designation to the supplier, drawing revision, quantity, packaging, identification records and agreed inspection requirements. Ask how the supplied product will be identified and how any proposed change will be communicated. Receiving staff should be able to compare the delivered marking and documentation with the approved order.
After installation, record the component identity and relevant operating observations using the equipment's normal commissioning procedure. If a previous bearing failed, send the failure information to engineering before repeating the same selection. The goal is a traceable decision that can be reviewed when operating conditions change.
Practical takeaways
- Define loads, speed, temperature and contamination alongside installation dimensions.
- Approve the full designation and interfaces before accepting a substitution.
- Tie lubrication and maintenance to the actual application and manufacturer's guidance.
Useful questions, clear answers
Can I replace a bearing using its dimensions alone?
Dimensions are insufficient for an approval. Compare the full configuration and manufacturer data with the application's loads, fits, clearance, sealing, lubrication and service requirements.
What should I send with a bearing RFQ?
Send the complete existing designation, drawings, duty, load and speed information, temperature, contamination, lubrication method and any failure history. Label uncertain inputs for engineering review.
Sources and further reading
- Rolling bearings: operating temperature and lubrication conditions ↗SKF · Accessed 2026-10-03
- Bearing Selection Process ↗SKF Evolution · Accessed 2026-10-03
- Rolling Bearing Know-How: Basic Live Training ↗Schaeffler Training Campus · Accessed 2026-10-03
- Rolling-bearing lubrication guidance ↗SKF · Accessed 2026-10-03
General engineering information. Validate the final specification with your supplier and application engineer.