4.1 The dry sand/rubber wheel abrasion test (Fig. 1) involves
the abrading of a standard test specimen with a grit of
controlled size and composition. The abrasive is introduced
between the test specimen and a rotating wheel with a
chlorobutyl or neoprene rubber rim of a specified hardness.
This test specimen is pressed against the rotating wheel at a
specified force by means of a lever arm while a controlled flow
of grit abrades the test surface. The rotation of the wheel is
such that its contact face moves in the direction of the sand
flow. Note that the pivot axis of the lever arm lies within a
plane that is approximately tangent to the rubber wheel surface,
and normal to the horizontal diameter along which the load is
applied. The test duration and force applied by the lever arm is
varied as noted in Procedure A through E. Specimens are
weighed before and after the test and the loss in mass recorded.
It is necessary to convert the mass loss to volume loss in cubic
millimetres, due to the wide differences in the density of
materials. Abrasion is reported as volume loss per specified
procedure.