Chain Drives - What to Consider

 

One of the main advantages of a chain drive is its ability to perform well under varying conditions. Despite this ability there are a number of rules for good design practice which if considered early in the design process will ensure the correct chain is selected and maxim results are achieved.

Minimum Ultimate Tensile Strength: this is the static load required to break the chain. Load or tension applied to the chain in service should never exceed 1/6^th of the chains Ultimate Tensile Strength. A roller chain should NEVER be loaded above 50% of its MUTS for even 1 cycle as doing so will permanently damage the chain.

Allowable Working Load: Roller chain with equal tensile strengths can have very different working load capacities, there is no constant relationship between a roller chains working capacity and its ultimate tensile strength. Certain chain manufacturers with a higher tensile strength could have a lower working load capacity.

Selecting Chain Sizes: There could be several suitable chains for any particular application, Loads, Speeds, Environment, Required service life; Costs will determine the final selection. Generally the lower cost drive will be powered by a single strand chain of the smallest pitch available to take the load required. The speed and number of teeth on the drive sprocket will also effect the selection of the chain size that is required.

As a general rule the smaller the pitch of chain the higher the operating speeds.