I~ FORE-AND-AFTER8. I Bulb Plate. Bulb Angle. Length of Centre Fore-and-Alters. Side Fore-and-Alters. - Fore-and- Mounting. Spacing Centre to Centre. Spacing Centre to Centre. Alters. 3' 0" 4'0" 5' 0" 3' 0" 4' 0" 5' 0" ins. ins. ins. ins. ins. ins. ins. ins. ins. iM. ins. ins. ins. ins. ins. ins. ins. ins. 6' 0" 2~X 2~X .36 6X.36 6~X .38 7X.38 6X3X.366~X3~X.38 7X3~X.38 8' 0" 2~X 2~X .38 7X.42 8X.44 9X.44 7X3~X.428X3X.44 9X3~X.44 10' 0" 2~X 2~X .40 8X.50 9~X .50 11X.50 8X3~X.509~X3~X.5011X3~X.50 Wood Centre Fore-and-Alters. Wood Side Fore-and-Afters. Spacing Centre to Centre. Spacing Centre to Centre. - 3' 0" 4' 0" 5' 0" 3' 0" 4' 0" 5'0" D B D B D B D B D I{D It ins. ins. ins. ins. ins. ins. ins. ins. ins. ins. 6' 0" 5H 7 6 7 6}S 7 5~~ 5~ 6 6}S 8' 0" 6~ 7 7~ 7 S 7 6~~ 6~ 7~ 8 10' 0" 8 7 8~ 8 9 9 8 7 8~ 9 -- A=Plain angle. BP=Bulb plate. P=Plate. D=Depth. B=Breadth. Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge. Depths for fore-and-alters are measured from the underside of the hatch covers to the lower edge. Sizes fot 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-alter. 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. • 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 deptbs given above: the thickness of plates, bulb andes and bulb plates should correspond to the thickness tabulated for the reduced deptbs with a minimum thickness of .30 Ineb; the deptlis and breadths of wood fore-and·alters may be 80 per cent. of those given In the tables for aide fore-and-afters, but the centre fore-and·aIters must be not less than 6\oi Inches wide. In ships between 100 fl)8t and 200 feet In lenlth, the sizes of the beams and fore-and-aftera are to be determined by linear interpolation. [Footnote In the eertlfled copy.] l\:) ~ -.::I ~ 1-4 Z 1-3 t;j ~ Z > ~o ~ ~~ ~a ~
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