Process of manufacture
68.—(1)  All steel forgings intended for use in the construction of hulls, boilers and their fittings, and machinery shall be made by the open hearth process, acid or basic.
(2)  The forgings shall be made from sound ingots, not more than the lower two-thirds of the ingot being utilised for the purpose. The sectional area of the body of the forging shall not exceed 20% of the sectional area of the original ingot, and no part of the forging shall have more than two-thirds of the sectional area of the ingot.