160.035-6—Construction of aluminum oar-, hand-, and motor-propelled lifeboats.
(a) General.
Aluminum lifeboats shall comply with the general requirements for the construction and arrangement of steel lifeboats unless otherwise specified.
| Length of boat not over (feet) | Bar keel, stem and sternpost (inches) | 5086-H112/6061-T6 | Gunwales 1 | Angle bar (inches) -5086-H112/6061-T6 | Flanged flat bar (inches) -5086-H112/6061-T6 | Shell plating (Brown and Sharpe gage) 2 | Independent air tanks | 5052-H32 | Side | Bottom | 6061-T6 | Side | Bottom | Built-in-air tanks | 5052-H32 | Side | Bottom | Inner shell | Bulkheads | 6061-T6 | Side | Bottom | Inner shell | Bulkheads |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 12.0 | 23/4x3/4 | 21/4x2x5/16 | 4x5/16 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 15 | 15 | |||||||||
| 14.0 | 23/4x3/4 | 21/4x2x5/16 | 4x5/16 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 15 | 15 | |||||||||
| 16.0 | 23/4x3/4 | 21/2x21/4x5/16 | 41/2x5/16 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 15 | 15 | |||||||||
| 18.0 | 3x3/4 | 21/2x21/4x5/16 | 41/2x5/16 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 15 | 15 | |||||||||
| 20.0 | 3x1 | 23/4x21/2x5/16 | 5x5/16 | 13 | 13 | 13 | 13 | 13 | 13 | 14 | 14 | 13 | 13 | 14 | 14 | |||||||||
| 22.0 | 3x1 | 23/4x21/2x5/16 | 5x5/16 | 12 | 12 | 12 | 12 | 13 | 12 | 14 | 14 | 13 | 13 | 14 | 14 | |||||||||
| 24.0 | 31/4x1 | 23/4x21/2x3/8 | 5x3/8 | 11 | 11 | 11 | 11 | 11 | 11 | 13 | 13 | 12 | 12 | 14 | 14 | |||||||||
| 26.0 | 31/2x1 | 23/4x21/2x3/8 | 5x3/8 | 10 | 9 | 11 | 10 | 11 | 10 | 12 | 12 | 11 | 11 | 13 | 13 | |||||||||
| 28.0 | 33/4x1 | 23/4x21/2x3/8 | 5x3/8 | 9 | 8 | 10 | 9 | 10 | 9 | 12 | 12 | 11 | 10 | 13 | 13 | |||||||||
| 30.0 | 4x1 | 3x23/4x3/8 | 51/2x3/8 | 9 | 8 | 9 | 8 | 9 | 8 | 11 | 11 | 10 | 9 | 12 | 12 | |||||||||
| 32.0 | 4x1 | 3x23/4x3/8 | 51/2x3/8 | 8 | 7 | 9 | 8 | 9 | 8 | 11 | 11 | 10 | 9 | 12 | 12 | |||||||||
| 34.0 | 4x1 | 3x23/4x3/8 | 51/2x3/8 | 8 | 7 | 8 | 7 | 8 | 7 | 10 | 10 | 9 | 8 | 11 | 11 | |||||||||
| 36.0 | 4x1 | 3x23/4x3/8 | 51/2x3/8 | 7 | 6 | 8 | 7 | 8 | 7 | 10 | 10 | 9 | 8 | 11 | 11 | |||||||||
| 1 Extruded shapes having substantially the scantlings of the angle bar gunwale are permitted. Where extruded shapes are used, a nosing as per § 160.035-3(j) is not required provided the extruded shape has at its heel a generously rounded curve. | ||||||||||||||||||||||||
| 2 Brown and Sharpe gage decimal values: 15 gage equals 0.05707, 14 gage equals 0.06408; 13 gage equals 0.07196; 12 gage equals 0.08081; 11 gage equals 0.09074, 10 gage equals 0.1019; 9 gage equals 0.1144; 8 gage equals 0.1285; 7 gage equals 0.1443, and 6 gage equals 0.1620. | ||||||||||||||||||||||||
(c) Welding.
(1)
Welding may be substituted for riveting in the following locations: Hoist plate to keel, disengaging gear grace plate to stem and sternpost, rudder attachment fitting to the sternpost, and the propeller shaft stern tube to the sternpost. When using 6061-T6 aluminum, the welded area is to be heat-treated and checked by X-ray to assure a satisfactory weld. When using 5086-H 112 aluminum, the welded area is to be checked by a nondestructive test method such as X-ray, ultrasonic waves or fluorescent materials, to assure a satisfactory weld. Other methods of checking aluminum welds will be given separate consideration. The welding shall be performed by a welder qualified by the U.S. Coast Guard, American Bureau of Shipping, or U.S. Navy Department, and only suitable electrodes shall be used. Details of the joints shall be indicated on the construction drawings submitted for approval.
(d) Dissimilar metals.
(1)
Where in the construction of aluminum lifeboats the use of dissimilar metals are employed such as, the installation of the mechanical disengaging gear, hand propelling gear, or engine, suitable insulation between the aluminum and these metals shall be used. Porous or absorbent materials shall not be used as insulating materials. Only non-porous materials such as plastics, rubber or neoprene base compounds, or micarta shall be used. Other suitable material will be given separate consideration. Fasteners used in joining dissimilar metals together shall be of the type that will minimize corrosion.
[CGFR 65-9, 30 FR 11467, Sept. 8, 1965, as amended by CGD 95-028, 62 FR 51213, Sept. 30, 1997]