(a) Process of manufacture.- The castings shall be
cast from metal melted or refined in any metallurgical plant
other than an iron ore smelting furnace, for the use of which
furnace permission in writing must be received from the Inspecting
(b) Chemical Composition.- The composition of the
iron as cast shall be left to the discretion of the manufacturer
but the maximum percentage of phosphorus or sulphur or both
may be specified by the Inspecting Authority, if he so desires.
(c) Moulding.- The castings shall be accurately moulded
in accordance with the pattern or working drawings supplied
by the Inspecting Authority with the addition of such letters,
figures or marks as may be specified and the drawings shall
include the tolerances specified in the Regulations.
Freedom from defects.- The castings shall be sound,
clean out of twist and free from blow holes distortion and
all surface and other defects. They shall be well dressed
or fettled and shall be machinable by normal methods.