Groove geometry determines how the belt sits and transmits load. The current international reference is ISO 4183:2026, which specifies principal dimensions for classical and narrow V-belt pulleys including SPZ, SPA, SPB and SPC. DIN 2211-1 remains a current German dimensional reference for narrow V-belt pulleys.
What the lettered dimensions mean in this catalogue
The model tables use P and O together with E, F, J, K, L, M and N. The drawing above is the controlling reference for where those letters are measured. Because construction type changes by diameter and groove count, do not copy one lettered value from a nearby model.
| Symbol | Use in this catalogue |
|---|---|
| P | Pitch/datum diameter used for drive ratio |
| O | Outside diameter used for physical clearance |
| Type | Construction arrangement shown in the family drawing |
| Bush | Recommended taper-bush designation |
| Max Bore | Maximum catalogue bore for the specified bush/model |
| E/F/J/K/L/M/N | Lettered construction dimensions read with the relevant type drawing |
Why angle and pitch are not decorative details
A belt that contacts the groove incorrectly can run hot, wear the sidewalls or sit too high/low. When replacing an unknown pulley, confirm the groove family before relying on diameter alone. For a new drive, use the belt manufacturer’s rating and minimum-diameter guidance in addition to the pulley dimensions.
Need help matching a pulley? Email [email protected] with the belt marking, shaft diameter and pulley measurements.