Means shall be provided for controlling the mill roll
temperatures to the specified temperature 65°C (69°F).
6.1.4 The clearance between rolls shall be adjustable from
0.2 to 8.0 mm (0.008 to 0.31 in.) as a minimum range of
adjustment. Roll clearance shall be determined by means of
two lead strips 10 6 3 mm (0.4 6 0.1 in.) wide, at least 50 mm
(2 in.) long, and 0.25 to 0.50 mm (0.01 to 0.02 in.) thicker than
the roll clearance to be measured. The lead strips shall be
inserted, one at each end of the rolls approximately 25 mm (1
in.) from the guides, while a piece of compounded rubber, with
Mooney viscosity in excess of 50 ML 1 + 4 at 100°C (212°F),
approximately 75 by 75 by 6 mm (3 by 3 by 0.25 in.) is passing
through the center portion of the rolls. The rolls shall be at the
temperature specified for mixing. After the lead strips have
passed through the rolls, measure the thickness of the strips to
the nearest 0.02 mm (0.001 in.). Tolerance on a roll clearance
shall be 610 % or 0.05 mm (0.002 in.), whichever is larger