A linear actuated chain test rig capable of accelerated test speeds and continuous wear measurements

Abstract

This article presents a novel linear actuated chain test rig, which is capable of accelerated test speeds and continuous wear measurements. The ability to measure chain wear in situ saves time and expense compared to a conventional sprocket driven rig because the traditional rig requires the chain to be dismantled in order to monitor wear. In situ chain measurement reduces errors significantly. The novel test rig does not have a traditional set up of rotary driven sprocket and chain but uses a pneumatic linear actuator to articulate a short section of chain, which is preloaded between two cantilevers. This design leads to a compact rig with only few moving parts and allows accelerated testing at high frequencies. Linear encoder displacement transducers are used to measure changes in chain length down to 0.06 µm at a rate of 4000 readings per second. Sample wear tests on different chains have been conducted to compare life test results with conventional sprocket-driven tests rig. A good correlation was obtained between the steady-state wear rate for three different brands of roller chain.