|
(a) Steel for plates shall be made by the open hearth, electric
furnace or basic oxygen process or any other process which
gives steel having equivalent specified properties.
(b) General deoxidation practice shall be appropriate to
the type of steel used, particularly where the deoxidation
practice influences the level of the elevated temperature
properties of steel.
(c) Rimmed steels may be permitted only for riveted drums
or shells made of plates having a nominal thickness upto 20
mm.
(d) Plates of carbon steel shall conform to one of the following
four grades of tensile strength:-
| (i) |
37 to 45 kgf/mm2 |
| (ii) |
42 to 50 kgf/mm2 |
| (iii) |
47 to 56 kgf/mm2 |
| (iv) |
52 to 62 kgf/mm2 |
(e) Semi-killed steel may be used for plates in C and C-Mn
steel with an upper limit of the tensile strength not exceeding
56 kg /mm2 and with thickness not exceeding 50mm under service
temperature condition 0-450°C.
|
