SATRA STM 140 Leather soling abrasion machine
The SATRA soling materials abrasion machine gives a straightforward and realistic abrasion test for shoe soling and heel materials. The test pieces are drawn from side to side in a straight line under load over an abrasive coated cloth supported on the horizontal bed of the machine. The cloth is moved slowly at right angles to the test piece so the test piece is always in contact with new abrasive cloth, maintaining constant cutting power.
The machine gives an average of abrasion through the entire thickness of samples. This can be achieved by abrading the two test pieces from alternative sides at the same time. Those pieces are 25mm (or 1 inch) square and the abrasive cloth is usually 80 grit. The loading on the test pieces is 0.56kg/cm2 (8lb/in2). Dial gauges measuring thickness loss are a standard feature of the machine.
To ensure the test results obtained are accurate it is necessary to remove the debris caused by abrading the sample. This is achieved by applying a vacuum to the test area. The SATRA machine has a built-in vacuum extraction point where a normal domestic vacuum cleaner (not supplied) can be connected.