Inch Sizes Standard Pilot Bore Timing Pulleys
Inch Sizes Standard timing pulleys are the basic type of pulleys for belts with trapezoidal profiles and inch pitch. Their design is according to ISO 5296.
They are made from steel, cast iron or aluminium alloy with a pilot bore, alternatively unbored.
The pulleys are supplied as a semi-finished product and the bore must be modified before mounting the pulleys on the shafts.
Pulleys Fields of Use
The XL, L, H, XH standard timing pulleys are designed for all types of XL, L, H, XH belts.
They are typically used in older machines with lower and medium performance, for example in packaging machines, in the ceramic, textile, food and tobacco industry and in many other machines.
In new applications, they are often replaced by HTD, STD or CTD profiles.
Pulleys Material
Steel, cast iron or aluminum alloy.
Other materials to order.
| Parameter | Standard |
|---|---|
| Surface roughness | ISO 254 |
| Balance quality grade | VDI 2060, ISO 1940 |
Caution
Cast iron pulleys at v < 30 m/s must be balanced.
Pulley Basic Profile
- Pulley XL for belts XL with pitch 5.08 mm
- Pulley L for belts L with pitch 9.525 mm
- Pulley H for belts H with pitch 12.70 mm
- Pulley XH for belts XL with pitch 22.25 mm
Pulley Code Description
Example:
30 XL 037 (Type 6F, Al Alloy)
| Code Part | Description |
|---|---|
| 30 |
Number of pulley teeth |
| XL |
Teeth pitch in mm and type of pulleys for belts STD |
| 037 |
Width of the belt in inches × 1/100 (0,37" = 9,398 mm) |
| 6F |
Type of construction |
| Al Alloy |
Pulley material |
Documents for Download
Dimensions and Parameters of Inch Sizes Standard Pilot Bore Timing Pulleys
TYMA CZ Data Sheets
Czech and English (PDF 1.90 MB)

