(i) These regulations cover both hot finished and cold drawn seamless boiler, superheater and heat exchanger tubes of ferritic and austenitic alloy steel grades.  These shall conform in all respects with the requirements herein specified.

(ii)  The seamless tubes conforming to other national/international standards which are known to be commonly used as being suitable for use as boiler and superheater tubes can also be used with the designations of the national/international standards, provided such materials are not specifically prohibited by the regulations.

(iii)  While making tubes to other national/internationals standards the allowable stresses of the respective standard shall be strictly followed while designing the tubes.

(iv) The design metal temperatures shall not exceed the following limits :-

            Grade                                                                      Temp.

                                                                      Degree C(Degree F)

T1, T2                                                                                          537 (1000)

T5, T9, T11, T12, T22, T91, 12X1Mf, X20CrMoV121,

TP 304, TP 304H, TP 304L, TP 310S, TP 316, TP316H,

TP 316L, TP321, TP321H, TP347, TP347H                                     648 (1200)