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Depths for

Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge.
fore-and-afters are measured from the underside of the hatch covers to the lower edge. Sizes for intermediate lengths and spacing are
obtained by interpolation. Where plates are specified, two angles of the size given for mountings, are to be fitted at the upper and at the
lower part of the beam. Where bulb plates are specified, two angles, of the size given for mountings are to be fitted at the upper part of
the beam or fore-and-after. Where bulb angles are specified, one angle, of the size given for mountings, is to be fitted at the upper part
of the section. Where the specified flanges of an angle are of different dimensions, the larger flange is to be horizontal.

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HATCHWAY BEAMS AND FORE-AND-AFTERS FOR SHIPS 200 FEET OR MORE IN LENGTH 1

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1 In ships not exceeding 100 feet in length, the depths of beams which are formed of plates and angles may be 60 per cent. of the depths given above; the depths of beams and steel fore-and-afters formed of bulb angle or bulb plate section may be 80 per cent. of the depths given above; the thickness of plates, bulb angles and bulb plates should correspond to the thickness tabulated for the reduced depths with a minimum thickness of .30 inch; the depths and breadths of wood fore-and-afters may be 80 per cent. of those given in the tables for side fore-and-afters, but the centre fore-and-afters must be not less than 61⁄2 inches wide. In ships between 100 feet and 200 feet in length, the sizes of the beams and fore-and-afters are to be determined by linear interpolation.

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Depths for

Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge. fore-and-afters are measured from the under side of the hatch covers to the lower edge. Sizes for intermediate lengths and spacing are obtained by interpolation. Where plates are specified, two angles, of the sizes given for mountings, are to be fitted at the upper and at the Where bulb plates are specified, two angles, of the size given for mountings, are to be fitted at the upper part of lower part of the beam. the beam or fore-and-after. Where bulb angles are specified, one angle, of the size given for mountings, is to be fitted at the upper part of Where the specified flanges of an angle are of different dimensions, the larger flange is to be horizontal. the section.

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RULE 12.-CARRIERS OR SOCKETS

Carriers or sockets for hatchway beams and fore-and-afters are to be of steel at least 1⁄2 inch thick, and are to have a width of bearing surface of at least 3 inches.

RULE 13.-CLEATS

Strong cleats at least 2%1⁄2 inches wide are to be fitted at intervals of not more than 2 feet from centre to centre; the end cleats are to be placed not more than 6 inches from each corner of the hatchway.

RULE 14.-BATTENS AND WEDGES

Battens and wedges are to be efficient and in good condition.

RULE 15. TARPAULINS

At least two tarpaulins in good condition, thoroughly waterproofed and of ample strength, are to be provided for each hatchway in an exposed position on freeboard and superstructure decks. The material is to be guaranteed free from jute, and of the standard weight and quality laid down by each Administration.

RULE 16. SECURITY OF HATCHWAY COVERS

At all hatchways in exposed positions on freeboard and superstructure decks ring bolts or other fittings for lashings are to be provided.

Where the breadth of the hatchway exceeds 60 per cent. of the breadth of the deck in way of the hatchway, and the coamings are required to be 24 inches high, fittings for special lashings are to be provided for securing the hatchway covers after the tarpaulins are battened down.

RULE 17.-CARGO AND OTHER HATCH WAYS IN THE FREEBOARD DECK WITHIN SUPERSTRUCTURES WHICH ARE FITTED WITH CLOSING APPLIANCES LESS EFFICIENT THAN CLASS 1

The construction and fitting of such hatchways are to be at least equivalent to the standards laid down in Rule 18.

RULE 18.-HATCHWAY COAMINGS AND CLOSING ARRANGEMENTS Cargo, coaling and other hatchways in the freeboard deck within superstructures which are fitted with Class 2 closing appliances are to have coamings at least 9 inches in height and closing arrangements as effective as those required for exposed cargo hatchways whose coamings are 18 inches high.

Where the closing appliances are less efficient than Class 2, the hatchways are to have coamings at least 18 inches in height, and are to have fittings and closing arrangements as effective as those required for exposed cargo hatchways.

RULE 19.-MACHINERY SPACE OPENINGS IN EXPOSED POSITIONS ON FREEBOARD AND RAISED QUARTER DECKS

Such openings are to be properly framed and efficiently enclosed by steel casings of ample strength, and where the casings are not protected by other structures their strength is to be specially considered. Doors in such casings are to be of steel, efficiently stiffened, permanently attached, and capable of being closed and secured from both sides. The sills of openings are to be at least 24 inches above the freeboard deck and at least 18 inches above the raised quarter deck.

Fiddley, funnel, and ventilator coamings are to be as high above the deck as is reasonable and practicable. Fiddley openings are to have strong steel covers permanently attached in their proper positions.

RULE 20.-MACHINERY SPACE OPENINGS IN EXPOSED POSITIONS ON SUPERSTRUCTURE DECKS OTHER THAN RAISED QUARTER DECKS

Such openings are to be properly framed and efficiently enclosed by strong steel casings. Doors in such cases are to be strongly constructed, permanently attached, and capable of being closed and secured from both sides. The sills of the openings are to be at least 15 inches above superstructure decks.

Fiddley, funnel and ventilator coamings are to be as high above the deck as is reasonable and practicable. Fiddley openings are to have strong steel covers permanently attached in their proper positions.

RULE 21.-MACHINERY SPACE OPENINGS IN THE FREEBOARD DECK WITHIN SUPERSTRUCTURES WHICH ARE FITTED WITH CLOSING APPLIANCES LESS EFFICIENT THAN CLASS 1

Such openings are to be properly framed and efficiently enclosed by steel casings. Doors in such casings are to be strongly constructed, permanently attached, and capable of being securely closed. The sills of the openings are to be at least 9 inches above the deck where the superstructures are closed by Class 2 closing appliances, and at least 15 inches above the deck where the closing appliances are less efficient than Class 2.

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