Section 6 Shell envelope framing

6.1.1 The section modulus of the side frames of single deck trawlers and fishing vessels need not be greater than 80 per cent of the modulus required by Pt 4, Ch 1, 6 Shell envelope framing, but in no case is the depth of the frame to be less than 60 mm. Where not specified the draught is to be taken as not less than 0,85D.

6.1.2 For two deck trawlers and two deck fishing vessels and all vessels requiring a load line, the requirements of Pt 4, Ch 1, 6 Shell envelope framing are to be complied with.

6.1.3 The section modulus of frames in the fore peak is to be the greater of the following:

1. 10 per cent greater than that required by Pt 3, Ch 5, 4 Shell envelope framing.

2. Z

   =

   (45D − 212) cm3.

6.1.4 The section modulus of frames in the aft end region is to be not less than that required by Pt 3, Ch 6, 3 Shell envelope plating.

6.1.5 Where frames are stopped at watertight flats they are to be bracketed.