COMPARISONS BETWEEN SAND BLAST AND CENTRIPETAL EFFECT ACCELERATOR TYPE EROSION TESTERS

There are two major types of erosion testing devices that are used thr oughout the world for quantifying particle impact erosion against a so lid surface. The first of these uses pressurised air to accelerate abr asive particles through a nozzle so that they impinge upon a target sp ecimen. The second adopts a rotating disc to accelerate abrasive parti cles using the centripetal effect so that they impinge upon a series o f targets arranged around the periphery of the disc. This paper report s the findings of a collaborative project that was designed to compare the performance and results obtained from a rig of each of the two ty pes mentioned above. The sand blast type rig was provided by The Depar tment of Powder Science Technology (POSTEC) at The Telemark Technologi cal Research and Development Centre (TEL-TEK), Porsgrunn, Norway while the centripetal effect accelerator was provided by The Wolfson Centre for Bulk Solids Handling Technology, University of Greenwich, London, UK. The test programme included tests against a wide range of materia ls that are commonly used in pneumatic handling facilities. (Pneumatic handling is a means of conveying and transporting powders and granula r solid materials in bulk in industrial process plant, through pipelin es using a gas as the carrier medium.) Olivine sand was used as the ab rasive and it was projected against the test specimens at velocities a nd concentrations commensurate with those seen in pneumatic conveyors. In all instances the materials used in the test programme were taken from the same batch so that scatter of experimental results due to spe cimen variation was minimised. The paper contains a series of recommen dations for erosion testing equipment. A discussion based on the resul ts and their applicability to the prediction of wear in pneumatic conv eyors concludes the paper.