Timing Belt Pulley Standard Tolerances
Pfeifer Industries’ timing belt pulleys are precisely made to exacting tolerances ensuring that the timing belt and timing belt pulleys perform as intended. Most people would agree that a gear is a precise, quality demanding CNC machined part that requires a certain degree of skill to manufacture. The manufacturing of a timing belt pulley is no different. Both a gear and a timing belt pulley go through many of the same manufacturing steps to be produced. In order to be made correctly, close tolerances have to be maintained throughout production. The overall performance and longevity of the timing belt is directly related to the accuracy of the timing belt pulleys’ manufacturing.
Pfeifer Industries follows the manufacturing quality control standards for timing belt pulleys dictated by the leading timing belt manufacturers:
And the standards of the following timing belt/timing belt pulley related associations.
- Rubber Manufacturers Association (RMA)
Mechanical Power Transmission Association (MPTA)
- IP-24 Synchronous Belts (MXL, XL, L, H, XH, and XXH Belt Sections)
- IP-27 Curvilinear Toothed Synchronous Belts (H3M, R3M, S3M, H5M, S5M, H8M, R8M, S8M, H14M, R14M, S14M, H20M, AND R20M Belt Pitches
International Organization for Standardization (ISO)
- ISO 5288:2001 Synchronous belt drives – vocabulary
- ISO 13050:1999 Curvilinear toothed synchronous belt drive systems
- ISO 5294:1989 Synchronous belt drives - pulleys
Whenever possible, Pfeifer Industries adheres to those quality control standards which are more stringent.
In order to manufacture a quality timing belt pulley, the correct timing belt tooth profile needs to be duplicated. Pfeifer Industries employs gear hobbing to reproduce the timing belt tooth profiles. The inspection process of the timing belt tooth profile (groove) is made on an optical comparator. The timing belt tooth profile must conform to an overlay provided by the timing belt manufacturer for a given number of timing pulley teeth. These overlays are often proprietary information of the timing belt companies and are only given to licensed manufacturers such as Pfeifer Industries. A different timing belt tooth profile overlay is necessary for each number of toothed pulleys.
The following charts and tables contain the standard tolerances used by Pfeifer Industries to aid in the design, manufacturing and inspection of the timing belt pulleys that Pfeifer Industries produces.