Comparison between the angles of wall friction measured on an on-line wall friction tester and the Jenike wall friction tester

A PhD project titled: “Direct on-line measurement of wall friction of coal as an indicator of handleability”, and sponsored by Corus plc., has arisen from a need to obtain real time information about the flow-ability of the coal, so troublesome batches can be detected before problems arise. The on-line wall friction tester essentially comprises a ‘skid’ plate that rest on the top free surface of a bulk solid being transported on a conveyor belt. The ‘skid’ plate is connected to a load cell via a drag link allowing the shear force between the ‘skid’ plate and bulk solid to be sensed as the latter is conveyed. This paper presents results comparing the on-line tester to the Jenike wall friction tester for two different bulk solids namely: crushed glass and coal. The effect of velocity on the on-line tester has also been studied.