This unit has been designed to introduce students to the effects of material fatigue using a sinusoidal variation of bending stress.
A 2800rpm motor rotates a specimen through a gear and pulley arrangement between 5600 or 1400 rpm. The specimens are held within ‘keyless’ chucks and loaded using a cantilever arrangement, with the load being applied through a Load hanger and a set of weights. The loading system cancels its own self-weight enabling any desired value of bending stress to be applied.
A digital interface displays the revolution count of the specimen. The revolution count can be tared before commencing testing. When specimen failure occurs, a micro switch stops the motor and the cycles to failure are registered on the digital interface. The count remains when the motor is not running. A safety guard shields all rotating parts.
Specially machined necked test specimens are provided in steel. These have a 4mm nominal neck diameter. All tooling is provided to allow the removal and fitting of these specimens. A full technical Instruction manual is supplied, which details full unit operation, experimental technique, example results and relevant theory.
