The next time your conveyors are undergoing routine maintenance – or have had to be stopped to repair a fault – take a few moments to count the teeth on the power chain’s sprockets.
If the conveyor was acquired at any time within the last 30 years, the chances are that the chains that drive it will be running on sprockets with an even number of teeth.
"About two decades ago when Asia emerged as a centre for conveyor manufacturing, a number of companies based their designs on existing product ranges which featured non-standard chain sprockets with an even number of teeth. The manufacturers considered that this offered greater choice when designing conveyor systems, but it created a problem," explains Peter Church, managing director of Letchworth-based FB Chain Ltd – a leading manufacturer and supplier of leaf chain, anchor bolts and chain sprockets to the materials handling industry.
He continues: "Before the 1980s it was rare to see any sprockets with an even number of teeth – and that was for good reason."
"A sprocket with an odd number of teeth will offer at least double the service life of a sprocket with even teeth," Peter Church explains.
"In simple terms, if a sprocket has an even number of teeth, the same tooth will be engaged by the same rollers on each rotation. This leads to uneven wear on the chain and sprocket and a shortened service life for both components.
"There is very little price difference between even and odd-toothed sprockets so it is perhaps surprising that even toothed sprockets have become so widely accepted."
FB manufacture and stock a full range of standard sprockets and platewheels for all simplex, duplex and triplex roller chains. Larger sprockets suitable for the many varied types of metric and imperial conveyor chain are available on short delivery lead times.