NACHI 15° contact angle, 55 x 100 x 21

This NACHI range covers 28 single row angular contact ball bearings with a 15° contact angle (C), a polyamide cage (Y) and flush-ground faces for universal matching (DU), from 15 to 95mm bore (outer diameters 32 to 150mm, widths 9 to 28mm). Select the size from the drop-down: each size has its own bearing number, load ratings and limiting speeds in the Model Details.

A single row angular contact ball bearing has a set contact angle in both rings, so it carries radial, axial or combined load, with any axial load in one direction only. For that reason these bearings are generally used in pairs or sets, and the DU flush grinding lets any two or more be mounted back-to-back (DB), face-to-face (DF) or in tandem (DT) in random combination. The model reference for these sizes is CYDU/GLP4: GL is the light preload symbol and P4 is the JIS class 4 tolerance symbol, the high-precision class that the 15° design is generally applied to.

Where this product is used

• Machine tool spindles and other precision spindle assemblies
• Gearboxes and speed reducers that carry combined radial and axial load
• Pumps and compressors
• Back-to-back, face-to-face or tandem paired arrangements

Features

• 15° contact angle (C): compared with the 30° design, higher speed and radial load capability with lower axial load capacity, axial load in one direction only
• Polyamide cage (Y), polyamide cages should be used below 120 °C
• Flush ground (DU): any two or more can be mounted back-to-back, face-to-face or in tandem in random combination
• Open design with no seals or shields
• Basic dynamic load rating 6.65 to 100 kN across the range

Key specifications

Available sizes

Fitting and use

Check the load and speed against the figures in the specifications before ordering, and apply a suitable safety factor. Limiting speeds apply to lightly loaded bearings with high quality grease or oil in proper quantity.

The table speeds are for a single bearing, and for contact angle C bearings they apply to JIS class 5 or higher precision.

Polyamide cages should be used below 120 °C.

Flush-ground bearings in a combination should not be mixed with bearings of other types or makes. For a 15° bearing the load factors depend on the ratio of axial load to static rating, so take the equivalent load factors from the range table instead of using a single value.

When fitting, apply force only through the ring that is being pressed on (the inner ring on a shaft, the outer ring in a housing), never through the other ring or the balls.

Choosing the right option

Contact angle. This range is the 15° (C) design. Compared with the 30° design it is faster and carries more radial load, with less axial load capacity, and the 15° design is generally applied to high precision bearings of JIS (ISO) class 5 or higher. For heavier axial load at lower speed the 40° (B) range in Related products is the alternative.

Mounting arrangement. Because these bearings are flush ground (DU), any two or more can be combined at random. DB (back-to-back) has a long load centre distance and greater moment rigidity, DF (face-to-face) has a short load centre distance and lower moment rigidity, and DT is tandem mounting. DB and DF sets carry axial load in both directions.

Ratings and mass in the tables are for one bearing. The model reference for these sizes is CYDU/GLP4: GL is the light preload symbol and P4 is the JIS class 4 tolerance symbol.

Three more 15° (CYDU) sizes are on their own pages: NACHI 7001CYDU (12 x 28 x 8mm), NACHI 7008CYDU (40 x 68 x 15mm), NACHI 7205CYDU (25 x 52 x 15mm).

The 40° (B) single row range, for heavier axial load at lower speed: NACHI 40° single row angular contact ball bearings (26 sizes).

For one unit that carries axial load in both directions, see the double row range: open (20 sizes), ZZ shielded 25 to 70mm bore (12 sizes), ZZ shielded 10 to 40mm bore (6 sizes).