Section 9 Dredgers, hopper dredgers, sand carriers, hopper barges and reclamation craft
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Inland Waterways Ships, July 2022 - Part 1 Regulations - Chapter 3 Periodical Survey Regulations - Section 9 Dredgers, hopper dredgers, sand carriers, hopper barges and reclamation craft

Section 9 Dredgers, hopper dredgers, sand carriers, hopper barges and reclamation craft

Parent topic: Chapter 3 Periodical Survey Regulations

9.1 General

9.1.1 The requirements of this Section are to be complied with, as applicable, in addition to the survey requirements of Pt 1, Ch 3, 2 Annual Survey – Hull requirements. Where surveys are required on dredging or hopper equipment such as gantries, bottom doors and their operating gear, positioning spuds and suction pipe attachments, these will be limited to the extent considered necessary by the Surveyor to be satisfied that their condition or malfunction will not adversely affect the ship’s structure.

9.1.2 When the ship is placed in dry dock or on a slipway, the Surveyor is to examine the hopper doors or hopper valves, ladders, spudwells, and their fittings where applicable.

9.2 Special Surveys

9.2.1 On ships under 10 years old:

  1. Hoppers are to be cleared and cleaned as necessary and examined.

  2. Where applicable, hopper doors or valves are to be opened and closed, so far as is practicable, but keel blocks need not normally be moved specially to permit this to be done.

  3. The integrity of hopper overflows and diluting water inlet and distribution structures are to be confirmed. Weir valves and sluices are to be tested to ensure proper operation, particular attention being paid to the lower weir, when weirs are fitted at more than one level.

  4. Attention is to be given to shell plating in way of hopper overflows.

  5. The attachment to the ship’s structure of all main items of dredging equipment, including gantries, ‘A’ frames and spud control gear supports, is to be carefully examined to ensure that no fracture or other damage is present.

9.2.2 On ships over 10 years old:

  1. Attention is to be given by the Surveyor to the structure in way of dredging pumps.

  2. Hopper doors and valves are to be checked for proper operation, and their hinges, control gear and other fittings are to be examined for wear or distortion. All seals and weardown strips are to be replaced if necessary, but a watertight seal is not normally required. Attention is to be paid to areas likely to be suffering from excessive erosion.

  3. Those items of dredging gear and equipment whose efficiency is not part of classification but whose failure or malfunctioning is, nevertheless, likely to affect the ship’s structure adversely, are to be examined to ensure that the structural integrity of the ship is maintained.

9.3 Thickness measurement

9.3.1 The requirements of Pt 1, Ch 3, 4.3 Thickness measurements are to be complied with at each Special Survey.

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