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(a) The steel shall not contain more than 0.05 per cent
of sulphur or phosphorus.
(b) A sulphur print test shall be taken from the material
of each charge used for rivet bars for the purpose of ensuring
that sulphur segregates are not concentrated in the core.
The stage in manufacture at which this test is made shall
be at the option of the Steel-Maker.
(c) When the material is required for flame cutting and/or
welding, the carbon content shall not exceed 0.30% and special
precautions shall be taken when the carbon content exceeds
0.26%.
When steels are intended for service temperatures over 700°F
the silicon content shall be not less than 0.10% or alternatively,
the material shall pass the proof test for creep quality of
carbon steel plates of boiler quality.
(d) Plates having thickness of 12 mm and less than that,
not intended for hot forming, can be supplied in unnormalized
or as rolled condition subject to the condition that the code
of manufacture provides for the same. For plates having
thickness more than 12mm,
not intended for hot forming, shall be supplied in the
normalized conditions:
Provided
that the normalizing may be exempted if it is demonstrated by
the manufacturer that equivalent properties can be produced by
the rolling subsequent cooling.
NOTE:- The boiler manufacturer may, if he so wishes order
a check analysis.
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