Section 3 Dredger Registered with Smooth Water Service

301. Application

The requirements are service.

to apply to the dredger which is intended to register with smooth water

302. Deduction of scantling

l. For the Dredgers which are intended to register with smooth water service, the scantlings of struc- tural members obtained from relevant Chapters may be reduced with the ratio given in Table 12.1. However, the reduced scantlings are not to be less than the minimum given in Table 12.1.

2. The reduction of other structural members other than that given in Table 12.1 are to be at the discretion of this society.

3. The deck beams, inner bottom platings and inner bottom longitudinals and structural members of deep tanks which are subject to heavy cargoes or concentrated loads are not to be less than that obtained from Par 1 and Par 2.

303. Height of hatch coaming, etc.

The coaming height of hatches and access openings are not to be less than that given in Table 12.2.

Table 12.2 Sill height of hatch coaming and access opening

304. Hatch covers

l. The closing of hatches may be of rainproof.

2. Where, there are no cargoes on hatch covers, the thickness of cover platings may be of 4.5 mm .

3. The hatch covers are to be provided with stiffeners with proper spacing, and the section modulus of hatch cover may be of the value obtained from the formula specified in Ch 9, 202. 2 by sub- stituting 1.7 for Æ .

305. Equipment

l. According to the Equipment Number obtained from the rules in Ch 11, the equipment which are one grade lower than that given in Table 11.1 may be used.

2. The weight of one anchor is to be of that given in Par 1 and the others may be of 85 % of the weight given in Par 1.

Ch 1 2

306. Airpipe

The height from deck to opening part of the pipes and closing appliances of air pipes which are leading to exposed deck are of at the discretion of this Society.