Before installing new chain, carefully inspect all sprockets and shaft bearings (sprocket replacement is recommended for maximum chain life). Make sure used sprockets teeth are not worn or hook shaped. Be sure sprocket is securely fastened at a right angle to the shaft, ensuring the sprocket does not oscillate on the shaft when rotated. Inspect for any looseness in the shaft, or any worn shaft bearings.
Proper tension is essential when installing new chain. A tight chain causes additional load on the chain which increases chain wear. Excessive slack causes chain vibration increasing chain fatigue.
Proper chain tension is obtained by adjusting the chain sag on the slack side of the drive. For most applications, chain should be installed with a sag depth of between 2% - 4% of the sprocket center distance (see Table VIII). When measuring sag, remove the slack from one side of the chain drive. This can be done by pulling on one side of the chain and rotating the sprockets in opposite directions. On the slack side of the chain drive, place a straight edge from sprocket to sprocket. From the straight edge, measure the amount of sag from the straight edge to the chain (see figure below). For drives with near vertical shafts, and drives subject to high shock loads, reverse directions or dynamic braking (see “large impact” in Table I, page 1), the chain should be installed almost taut. Inspect such drives regularly for correct chain tension. Standard drive chain tension should be checked periodically.
HKK Chain's unique cold-forged solid bushing and solid roller design dramatically reduces the initial “break-in” or “run-in” amount of elongation that occur with most split bushing chains. However, a small amount of break-in may occur. It is recommended the chain be inspected after initial operation.