A roller chain consists of inner and outer links. The tabs on the outer links are fitted with steel pins which fit into the steel sleeves on the tabs on the inner links. The sleeves of the inner links are fitted with rotatable rollers made from hardened steel. This permits a smooth rotational movement between the rollers and the sprocket, hence the name roller chain.
The chain pitch is calculated based on the centre-to-centre distance between the pins.
However, to determine the correct type of chain, not only the inside dimension, but also the roller diameter and the internal width between the links are important. This is due to the fact that the roller chains are available which correspond to various standards such as BS, ANSI and ASA. Although these chains have the same inside dimensions, they differ from each other in terms of the roll diameter and the internal width between the chain links.
Roller chains come as standard in simplex, duplex and triplex versions in each inside dimension. Thanks to the extensive product range, a suitable chain is available for each market segment.
There is no limit to how far a roller chain can be extended by using connecting links; chains are available in many designs and materials. Possible materials are steel or stainless steel, but also a nickel-plated or a hardened version, or a version with a different surface treatment. In addition, chains made of special plastic combinations are available specifically for humid environments and the foodstuffs industry.
A suitable chain drive can be found for each specific field of application. A suitable solution is available for each drive depending on environmental factors and load fluctuations, including self-lubricating, maintenance-free chains, but also specially reinforced chains, if necessary. In addition, there are also countless possibilities when it comes to the cleats, track rollers, coatings, hardened pins and bushings, materials, tolerances, dimensions and hardness grades.
When a high degree of accuracy is required in the case of two or more chains running in parallel, one available option is the "Match & Tagged" service: The difference in lengths in such chains is a maximum of 0.5 mm, depending on the total length.
The following standards are of significance to chain drives: ISO 1977, ISO 606, ISO 1275, DIN 8167, DIN 8181, DIN 8188, DIN 8187 and BS 228.
