Cage materials compared
The cage carries no load — but it governs speed, noise and robustness. The materials at a glance, with the common manufacturer codes.
| Material | Typical codes | Temperature range | Properties & use |
|---|---|---|---|
| Pressed steel | J (SKF), no suffix | up to approx. 300 °C (ZKL) | The standard for deep groove and many roller bearings: robust, heat-resistant, economical. First choice when nothing special is required. |
| Machined brass | M / MA / MB | up to approx. 250 °C (ZKL) | Chosen where high cage strength is required, at high temperatures and where the cage must be guided on the ribs. Heavier, costlier. |
| Polyamide PA66, glass-fibre reinforced | TN9 (SKF), TVP/TVH (FAG) | approx. −40 to +120 °C continuous | Quiet, low-friction, good emergency-running properties. Its elasticity and low mass are favourable under shock loads and high accelerations and decelerations (Schaeffler, ZKL) and under tilting of the bearing rings (Schaeffler). Limits: continuous temperatures above ~120 °C accelerate ageing; oil additives and, at high temperatures, aged oil can shorten cage life. |
| PEEK | manufacturer-specific | well above PA66 | High-performance polymer cage for spindle bearings and high speeds at elevated temperatures — light, chemically resistant, expensive. |
| Machined steel | F / FA / FB | up to approx. 300 °C (ZKL) | For high temperatures and heavy duty where brass is insufficient or unwanted; also on very large bearings. |
Rules of thumb
Low-noise demands favour polyamide, standard applications pressed steel; high cage strength, high temperatures and rib guidance call for machined metal cages. The permissible speed depends on the cage execution: for cylindrical roller bearings with machined brass cages, Schaeffler cites a significantly higher limiting speed with oil lubrication — the catalogue value of the specific execution applies. Shock alone is no reason to avoid polyamide: Schaeffler and ZKL explicitly cite the elasticity and low mass of polyamide cages as an advantage under shock loads and high accelerations. Above roughly 120 °C continuous, polyamide cages are ruled out — metal cages or high-temperature executions apply. Cage codes are manufacturer-specific; check the suffix glossary for a specific designation, and carry the cage execution over when replacing a bearing.