Chains & Accessories

Roller chains are a form of drive chain used in transmission of power in mechanical operations, such as conveyors and vehicles. Often used with a sprocket the chain themselves they comprise of a chain link separated by individual cylindrical rollers that slots into the teeth of the sprocket that drives the chain. They can come in single link, double link and even triple link designs depending on the application they are being used in.

The Cromwell range features products from many well-known manufacturers including, Dunlop BTL, Rexnord and Linkbelt, so you can be assured of quality.

What are roller chains used for?

Roller chains can be used in a variety of applications. Some types of roller chains you will see every day like those fitted on vehicles like motorcycles. Others you will find in industrial areas such as warehouse roller doors and conveyor belts in manufacturing plants.

Types of roller chains

Roller chains come in different varieties; the kind you require will depend on the application you require it for. The most common types of chains are listed below, along with their key features and benefits.

Simplex roller chains - These are chains consisting of a single row of cylindrical roller links. They are the most common type of roller chain.

Duplex roller chains - Duplex roller chains feature a double row of cylinder links.

Triplex roller chains - As the name already alludes to these roller chains feature three rows of cylinder links.

The above are the most common types, although, quadruple and quintuple link chains are also used.

Roller chains also come in different thicknesses and pitches (the distance between links, measured from one link centre the next), smaller pitch chains have the advantage of smoother running. The thickness and pitch of the chain you will need will be dependent of application type and drive type.

What are roller chains made of?

Roller chains are usually made of either metal or plastic materials. The most common metal chains are constructed from steel or hardened steel or stainless steel. Plastic chains are usually made from nylon, acetal, or polypropylene. In some instances, a plastic and metal combination may also be used.
The type of materials you'll require your chain to be made from comes down to several factors such as heat, load, noise as well as the conditions in the working environment. If you're still unsure as to the right choice, we would recommend talking to a specialist

Considerations when choosing a chain

There are a few key factors to consider when choosing a roller chain, most of this boils down to technicalities and mechanical specifications.

Tensile strength - This is the tension load at which the chain will fail.

Maximum allowable load - The tension rating for which the chain will carry when running. It is in the interest of safety that this is not exceeded.

Chain weight - The weight of the chain per unit, this varies with pitch and materials used etc.

As always taking stock of the environmental conditions is a consideration as moisture can cause corrosion and excessive heat can cause metal to expand.

Understanding roller chain standards

British Standard / DIN / International Standards Organization (ISO) are governed by European standards committees. The standards that govern and categorise roller chains is ISO Standard 606 the number relates to the chains pitch in 1/16" increments, these are shown in millimetres.


How do I lubricate a roller chain?

Like all moving parts making sure that your roller chain is well lubricated will not only keep it running smoothly, but will also help protect it from wear and tear caused by use as well as providing protection against corrosion. Chains can be lubricated in various ways including manual brushing, spray application, drip and oil baths. As with any lubrication application, ensure that the right type of lubricant is used, this will help improve the lifespan of the chain.

What are the main parts of a roller chain?

Roller chains are all constructed in much the same way. They consist of a pin, bushing, roller, pin link plate and roller link plate.