Section 7 Miscellaneous Machinery Requirements

701. Starting arrangements

1. The capacity of the air receivers is to be sufficient to provide without reloading not less than 12 consecutive starts of the propulsion engine, if this has to be reversed for going astern, or 6 consec- utive starts if the propulsion engine does not have to be reversed for going astern.

2. If the air receivers serve any other purposes than starting the propulsion engine, in addition to the capacity required by Par 1, they are to have a sufficient capacity for these purposes.

3. The capacity of the air compressors is to be sufficient for charging the air receivers from atmos- pheric to full pressure in one (1) hour as specified in Pt 5, Ch 6, 1101. of the Rules for the Classification of Steel Ships, except for a ship with the Ice class IA Super, if its propulsion en- gine has to be reversed for going astern, in which case the compressor is to be able to charge the receivers in half an hour.

702.

Sea inlet and cooling water systems

1. The cooling water system is to be designed to ensure supply of cooling water when navigating in ice.

2. To satisfy Par 1, at least one cooling water inlet chest is to be arranged as follows. However, the ship with Ice class ID may not comply with the requirements in (2), (3) and (5).

(1) The sea inlet is to be situated near the centerline of the ship and well aft if possible.

(2) As guidance for design, the volume of the chest is to be about 1 m for every 750 kW engine output of the ship including the output of auxiliary engines necessary for the ship's service.

(3) The chest is to be sufficiently high to allow ice to accumulate above the inlet pipe and the

height of sea chest is not less than the value obtained from the following formula.

= volume of sea chest specified in (2) and, inlet pipe is to be not located higher than from the uppermost of sea chest.

(4) A pipe for discharge cooling water, allowing full capacity circulate, is to be connected to the chest. Here, "full capacity of cooling water" in means that the cooling water is used for the following purposes

(1) Main propulsion system(main engine, power train, shafts)

(2) prime movers for generator

(3) main boiler and primary equipments of auxiliary boiler

(5) The open area of the strainer plates is not to be less than four (4) times the inlet pipe sec- tional area.

3. If there are difficulties to meet the requirements of Par 2 (2) and (3), two smaller chests may be arranged for alternating intake and discharge of cooling water. In this case, the requirements in Par

2 (1), (4) and (5) are to be complied with. If the volume and height are not comply with 2 (2) and (3), inlet and outlet pipes of cooling water is to be connected to sea chest.

4. Heating coils may be installed in the upper part of the sea chest.

5. Arrangements for using ballast water for cooling purposes may be useful as a reserve in ballast condition but cannot be accepted as a substitute for sea inlet chest as described above.