Number of threads of the worm

Obtained value of a_w should be rounded off to the greater side according to standard series given in table 6.5.

Table 6.5

Standard values of the centre distance a_w of the worm gearing

Note. Series 1 should be preferred to Series 2.

In our case: u = 20, z^w = 2, z^g = 2×20 = 40 ≥28

= 0.212×40 = 8.48 round off to the = 10

.

The obtained value of a_w round off to the 200 mm.

6.5.2. Determine the axial module

and round off obtained value according to standard series given in table 6.6.

Table 6.6