11
Prior to deformation testing, the ball must be pre-compressed through a distance of
2.54 cm (1.0 inches) three times on each of three perpendicular axes in order to
remove any 'set' in the ball. One pre-compression should occur on each axis in
succession, until nine pre-compressions in all are completed. This is carried out on a
pre-compression jig. See Figure 2.
(1)
A ball must pass through a ring
gauge (under its own weight) with
an internal diameter of:
Ball Type 1 and Type 2:
6.86 cm (2.70 inches)
Ball Type 3:
7.30 cm (2.87 inches)
Stage 1 (Green) ball:
6.86 cm (2.70 inches).
(2) A ball must not pass through a ring
gauge (under its own weight) with an
internal diameter of:
Ball Type 1 and Type 2:
6.54 cm (2.57 inches)
Ball Type 3:
7.00 cm (2.76 inches)
Stage 1 (Green) ball:
6.30 cm (2.48 inches).
Figure 1. Size – Test Method ITF TB 02/01.
Figure 2. Pre-Compression – Test Method ITF TB 03/01.
