1. Not water‑resistant, not high‑temperature resistant (long‑term <110°C).

2. Brittle - can fracture under shock loads.

3. Lubricant must be compatible with phenolic resin (avoid certain synthetic oils containing esters).

4. Manufacturers provide speed limit curves (dn value charts) - they can be used for calculation.

5. No standard life model - typically estimate as half the designed bearing life.

1. Very high speed bearings (precision machine tool spindles, angular contact ball bearings).

2. Low density, low centrifugal forces, flexible.

3. Typical grades: M208, M209 (FAG), BX (SKF).

1. Pre‑soak cage in target humidity and temperature for 24 hours, measure pocket dimensional change.

2. Cage material must be compatible with the lubricant. 

1. Strict temperature limit: -30°C to +110°C (short‑term 120°C).

2. Hygroscopic – dimensional changes (0.2-0.5% size increase per 1% moisture uptake) may cause interference.

3. Not for vacuum (outgassing) or strong acids/alkalis.

4. No widely accepted fatigue life model; moisture absorption and ageing make calculations unreliable.

5. Centrifugal deformation can be estimated, but creep cannot be quantified.

6. Speed/temperature can only be assessed using material limits - precise life prediction not possible.

7. Life: the cage is often the “weakest link” – schedule first inspection at 30-50% of calculated bearing life.

8. Field judgement: if cage crumbles or melting smell appears, stop immediately.

9. Empirical life: under rated conditions, usually no more than 15,000 hours - mandatory replacement.

1. Small‑to‑medium bearings, home appliances, automotive parts (low noise, low cost).

2. Allows slight contact between rolling elements and cage without generating metallic wear particles.

3. Some elasticity, not highly sensitive to contamination.

1. In high‑speed applications, if measured temperature rise exceeds 70°C, switch to a machined cage.

2. Temperature: material property vs. temperature curves are openly available.

3. Hand‑rotating noise: “clicking” sounds indicate pocket wear – shorten relubrication intervals.

4. Inspection: red wear debris on cage surface indicates insufficient lubrication or deformation.

1. Surface zinc or phosphate plated – limited rust resistance.

2. Relatively large clearance between rolling elements and pockets – can cause noise and friction.

3. At high speed, centrifugal force may cause deformation or fracture.

4. Load: centrifugal and inertial forces can be calculated using bearing dynamics, but stiffness scatter of pressed parts makes results uncertain.

5. Speed: limiting speed from bearing catalogues can be used, but individual cage fatigue life cannot be accurately calculated.

6. Life: no standard cage life model – usually assumed same as calculated bearing life (in reality often shorter).

1. General industrial bearings (deep groove ball bearings, cylindrical roller bearings) – low cost, high volume.

2. Moderate temperature range (-40°C to +150°C), insensitive to most lubricants.

3. Suitable for low to medium speed, moderate loads – not for very high speeds because pressed construction has poor balance.

1. Alignment correction: if measured shaft tilt >50% of bearing rated angle, go to larger series or add a bearing.

2. Low‑speed heavy‑load (e.g., dryer cylinders): add 5–10% MoS₂ to grease – life extension factor up to 2×.

1. Life calculation requires misalignment life reduction factor.

2. Use of FEA or ISO/TS 16281 tilt correction factors.

1. High friction between roller spherical base and inner ring rib – needs high‑viscosity oil.

2. Self‑alignment limited (typically 2°–3°), not a universal joint replacement.