As standard, toothed belt pulleys are available in undrilled, pre-drilled or clamping bush variants. The clamping bush variant, also known as a taper or taperlock variant, is always used in combination with the associated clamping bush. The undrilled and pre-drilled variants must first be provided with a bore hole and possibly with a key way and a threaded hole. The clamping bush variant is equipped as standard with a conical bore and threaded holes for fastening the bush to the shaft. The associated clamping bushes are available with bore holes in varying sizes and key ways in metric and imperial sizes; the matching (socket head) screws also come with the bushes. The major advantages with using a clamping bush lie in the fact that the pulley and shaft do not have to be modified beforehand and that mounting and removal are very simple.
The most common toothed belt pulleys with a clamping bush are available from stock, e.g. the Powergrip HTD, Powergrip GT and PolyChain GT pulleys. The pulleys with imperial dimensions (L and H) are also mostly available from stock. Metric pulleys (T and AT) are only available as undrilled or pre-drilled variants as standard. The PolyChain toothed belt pulleys can be found in the "PolyChain toothed belt pulleys" category. Depending on the variant and number of teeth, the pulleys use either flanges and/or a hub as standard. Furthermore, we supply toothed belt pulleys to match customer specifications, and we can alter standard pulleys according to customer requests or designs.
Toothed belt pulleys are mostly made of steel, cast iron (GG) or aluminium (ALU) and are available for special applications in other materials such as plastic or stainless steel. Of course, it is also possible to apply a particular surface treatment to the pulleys if the ambient conditions require it.
Several factors determine which toothed belt type is best suited to a particular drive, for example the application (what is being driven?), the power to be transferred, the desired speed (acceleration or deceleration) as well as the centre distance of the pulleys. It is also important to know what ambient conditions are present and whether there are any space limitations (what is the maximum permissible diameter and width of the pulleys?).
Common standards for toothed belt drives are DIN7721 and ISO5294. Finally, it is important whether the drive needs to be static-conductive to meet ISO9563 (ATEX environments).