Section 13 Single pass loading

13.1.1 The requirements of this Section are to be applied to all ore carriers with a deadweight greater than 200 000 tonnes. The requirements are for single pass loading where the maximum permissible cargo intake per cargo hold may be loaded in a single loading pour.

13.1.2 Where the requirements of this Section have been complied with, then, on application from the Owners, the descriptive note Single pass loading may be entered in column 6 of the Register Book, see Pt 1, Ch 2, 2.8 Descriptive notes.

13.2.1 In addition to the plans required for submission by Pt 3, Ch 1, 5.2 Plans and supporting calculations and as detailed in the applicable Chapters, the following information is also to be submitted:

1. Maximum permissible cargo in each cargo hold.

2. Cargo mass curves for a single and adjacent hold loadings taking into account the cargo overshoot defined in Pt 4, Ch 11, 13.4 Cargo loading conditions for design assessment 13.4.1.(e).

3. One or more cargo loading sequences intended for single pass loading, see Pt 4, Ch 11, 13.2 Information required 13.2.2.

4. Details of ballast and deballast piping arrangements and pumping capacity.

5. Specification of loading computer.

13.2.2 The cargo loading sequences as required by Pt 4, Ch 11, 13.2 Information required 13.2.1.(c) are to include the following:

1. Start and end times of each cargo pour and the intended loading rate.

2. Start and end times of each deballasting operation and the intended discharge rate.

3. Intermediate points (in time) during pours and between pours. In general, the interval between intermediate points is not to be greater than 1 hour.

4. The ship’s loading condition, including the ship’s draughts at the fore and aft perpendiculars, amount of cargo in each hold and amount of ballast in each tank, and the still water bending moments and shear forces, are to be provided for each point (in time) of the loading operation specified in Pt 4, Ch 11, 13.2 Information required 13.2.2, Pt 4, Ch 11, 13.2 Information required 13.2.2.(b) and Pt 4, Ch 11, 13.2 Information required 13.2.2.(c).

13.3.1  Pour. A pour is defined by the start and finish of loading of a cargo hold. A pour finishes when the loading equipment changes position to a new cargo hold.

13.3.2  Overshooting. Overshooting is to be taken as the consequence of mistiming the loading of cargo, resulting in cargo overloading.

13.4.1 For the purpose of the design assessment, the following conditions are assumed:

1. Cargo loading and deballasting operations are coordinated, with the deballast capacity and arrangement of the vessel designed to accommodate the specified loading sequences.

2. The cargo is distributed symmetrically in a hold space.

3. Deballasting is carried out for each pair of symmetrical port and starboard tanks simultaneously, so that each pair of symmetrical port and starboard ballast tanks contain equal amounts of water ballast throughout deballasting operations.

4. To improve deballasting and stripping, the trim of the ship is to be, in general, by the stern throughout the cargo loading operation.

5. A cargo overshoot per cargo hold is taken as 10 per cent of the maximum permissible hold cargo mass or 3000 tonnes, whichever is the lesser, but not less than 5 per cent of the maximum permissible hold cargo weight, in any case. A higher cargo overshoot may be specially considered.

6. Loading more than one cargo hold simultaneously in a single pass, i.e. simultaneous filling of two or more holds, will be specially considered. The specific loading conditions are to be submitted for appraisal in addition to the condition(s) for standard single-pass loading.

13.5.1 The following criteria are to be complied with in all cargo loading sequences:

1. Still water bending moment and shear force are within the allowable limits.

2. Single hold loading is within the allowable hold mass curve.

3. Two adjacent holds loading are within the allowable hold mass curve.

13.5.2 Arrangements and scantlings of local stiffeners and plating within the cargo hold region are to comply with Pt 4, Ch 11, 1 General to Pt 4, Ch 11, 12 Forecastles with consideration of the maximum permissible cargo mass per hold in the loading manual and the cargo overshoot specified in Pt 4, Ch 11, 13.4 Cargo loading conditions for design assessment 13.4.1.(e).

13.5.3 The primary structure and plating within the cargo hold region are to be assessed in accordance with the ShipRight SDA Procedure for Ore Carriers.

13.6.1 The deballasting capacity of the vessel, including arrangement of ballast tanks, pumps and relevant piping system, is to be sufficient for the loading operations as agreed in the approved loading plan.

13.6.2 A smaller diameter stripping system with separate main and branch lines may need to be provided in order to achieve the required deballasting capacity.

13.7.1 All loading sequences of single pass loading, maximum loading rates and ballast pumping details are to be submitted for approval and included in the Loading Manual. Loading conditions at intermediate points as described in Pt 4, Ch 11, 13.2 Information required 13.2.2.(c) need not be included in the Loading Manual.

13.8.1 The ship is to be installed with sensors for remote measurement of water ballast, fuel oil and ship’s draughts.

13.8.2 In addition, it is recommended that an interface with the onboard loading computer, connecting to the installed sensors detailed in Pt 4, Ch 11, 13.8 Loading computer 13.8.1, is to be provided to check the ship’s condition during loading and unloading.