7.1.6 Conclude the mixing cycle by passing the rolled batch
endwise through the mill six times with an opening of 0.8 mm
(0.031 in.), to improve the dispersion.
7.1.7 Pass the batch four times through the mill at a setting
of 6 mm (.25 in.), folding it back on itself each time.
7.1.8 Weigh the batch, remove the test specimens for
Mooney viscosity in accordance with Test Method D 1646 or
cure meter in accordance with Test Method D 2084, or both,
and sheet out the remainder to 2.2 to 2.4-mm (0.087 to
0.094-in.) thickness after shrinkage has taken place.
7.2 Internal Mixer Mixing Procedure:
7.2.1 The compound is usually prepared in two stages: the
first one always in the internal mixer and the second either in
the internal mixer or on the standard mill.
7.2.2 The initial internal mixer temperature will be either
indicated or be such that the required discharge temperature is
reached.
7.2.3 The rotor speed shall be 8.16 rad/s (77 rpm), unless
otherwise specified.
7.2.4 Cut the rubber into pieces suitable for fast feeding.
7.2.5 Prepare the mix according to specified instructions
regarding the order and time of material addition.