Tsubaki's groundbreaking 'seventh generation' ANSI standard chain employs an innovative bushing system that greatly improves internal lubrication and extends wear life by 100% in the most popular RS80 to RS140 sizes. A combination of the new 'lube groove' bushing and an exhaustive testing regime also means that the new ANSI standard RS roller chain has a 33% higher kW rating. The new 'G7' chain was launched across Europe during October 2006.

Independent testing and field data show that wear in the pin/bushing joint is usually the limiting factor in overall chain life, particularly in externally lubricated chain types such as ANSI standard roller chain.

(The chain bushing is located between the solid bearing pin and external roller).

Tsubaki has committed a significant amount of its research and development resources to making improvements in this area, to reduce wear and effectively prevent chain elongation over a longer period of time.

The result is a patented lube groove bushing, the grooves themselves providing an internal reservoir for lubricant where the chain needs it most, which has a dramatic effect on both chain performance and longevity.

Tsubaki's G7 bushings utilise a new production technique to enable a series of grooves to be incorporated on the inner surface of a cold forged, extruded bush.

The new process results in a very precise cylindrical profile for better surface contact between the pin and bushing, and improved lubricant retention.

The patent design lube groove bush (LG) ensures that the chain is optimally lubricated, particularly in real world conditions where inconsistent external lubrication is a factor.

The result is a chain that lasts significantly longer in the field.

When tested, G7 chain lasted twice as long as Tsubaki's previous generation ANSI chain - and up to 4x longer than some comparatively priced alternatives from leading US and European competitors.

Increased wear life equates to lower maintenance costs, reduced downtime and increased reliability.

Overall equipment efficiency (OEE) costs are also reduced since the purchase cost is offset over a longer period of time - the price of G7 chain is unchanged over that of the previous generation.

As OEE costs feature more frequently in company thinking the evidence is building up to show that the cheapest chain is not always the cheapest solution and that higher quality products can significantly reduce costs.

Rigorous testing has also resulted in an increased kW rating - 33% higher for all chain sizes in the range from RS80 to RS240.

Only recently have ISO standards for fatigue testing link plates included a cyclic fatigue test, rather than a test just for linear tensile strength.

ISO requires a 5million cycle test, Tsubaki test to 10 million cycles, resulting in a higher kW rating for the Tsubaki G7 chain.

Customers can now benefit from enhanced power handling capability and an extended service life, or in some circumstances a more compact and less costly chain installation, the former being of more relevance to maintenance and replacement applications and the latter to OEMs.

A number of other innovations also contribute to this performance improvement.

Rollers are heat-treated and shot peened to give added durability and fatigue life in high-speed applications.