For pipes covered by the above regulations the following
minimum wall thicknesses are recommended for those Administrations
which do not have national regulations:
1 Scupper and discharge pipes, where substantial
thickness is not required, and venting pipes other than specified
in 3 below:
-
.1 For pipes having external diameter equal to
or less than 155 mm thickness should not be less than 4.5 mm;
-
.2 For pipes having external diameter equal to
or more than 230 mm thickness should not be less than 6 mm.
Intermediate sizes should be determined by linear interpolation.
2 Scupper and discharge pipes where substantial
thickness is required:
-
.1 For pipes having external diameter equal to
or less than 80 mm thickness should not be less than 7 mm;
-
.2 For pipes having external diameter of 180 mm
thickness should not be less than 10 mm;
-
.3 For pipes having external diameter equal to
or more than 220 mm thickness should not be less than 12.5 mm.
Intermediate sizes should be determined by linear interpolation.
3 Venting pipes in position 1 and 2 leading to
spaces below the freeboard deck or to spaces within closed superstructures:
-
.1 For pipes having external diameter equal to
or less than 80 mm thickness should not be less than 6 mm;
-
.2 For pipes having external diameter equal to
or more than 165 mm thickness should not be less than 8.5 mm.
Intermediate sizes should be determined by linear interpolation.