Section 3 Service group factors
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Special Service Craft, July 2022 - Part 3 General Requirements and Constructional Arrangements - Chapter 5 Anchoring and Mooring Equipment - Section 3 Service group factors

Section 3 Service group factors

3.1 General

3.1.1 The masses of anchors and the diameters and lengths of chain cable required by Table 5.5.1 Anchors and Table 5.6.1 Chain cable respectively are for craft in Service Group G4.

3.2 Craft in service groups Zone 1 to Zone 3

3.2.1 For craft in service groups Zone 1 to Zone 3, the number and mass of anchors are to comply with Pt 3, Ch 5, 5.9 Anchors for vessels in service groups Zone 1 to Zone 3; the strength and length of chain cables are to comply with Pt 3, Ch 5, 6.9 Anchor chains and wire cables for vessels in service groups Zone 1 to Zone 3.

3.3 G1 craft

3.3.1 For craft in Service Group G1, the equipment is generally to be that required for craft in Service Group G2; proposals for further reductions will be specially considered.

3.4 G2, G3, G2A and G4 craft

3.4.1 For craft in Service Groups G2, G2A, G3, and G4, the mass of the anchor required by Table 5.5.1 Anchors may be multiplied by the following factors:

Service Group G2 0,60
Service Group G2A 0,65
Service Group G3 0,73
Service Group G4 1,00

3.4.2 The length and diameter of chain cable are to be those required by Table 5.6.1 Chain cable corresponding to the reduced anchor mass given in Table 5.5.1 Anchors.

3.4.3 Towlines and mooring lines are to be those required by Table 5.7.1 Towlines and mooring lines corresponding to the equipment number as determined from Pt 3, Ch 5, 2 Equipment Number.

3.4.4 For service craft on particular duties, a further reduction in the mass of the anchor may be given in accordance with Pt 3, Ch 5, 4 Craft type factors.

3.5 G5 craft

3.5.1 Craft in Service Group G5 are considered for the purposes of this Chapter to be unrestricted in their service, and the equipment is to be in accordance with Pt 3, Ch 13 Ship Control Systems of the Rules for Ships.

3.6 G6 craft

3.6.1  Service Group G6 covers yachts and patrol craft having unrestricted service.

3.6.2 For yachts, the mass of the anchors required by Table 5.5.1 Anchors may be multiplied by the craft type factor indicated in Pt 3, Ch 5, 4 Craft type factors. The length and diameter of chain cable are to be those required by Table 5.6.1 Chain cable corresponding to the reduced anchor mass given in Pt 3, Ch 5, 4 Craft type factors.

3.6.3 For patrol craft, the equipment is to be in accordance with Pt 3, Ch 13 Ship Control Systems of the Rules for Ships for unrestricted service.


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