JIS G3461 Standard Boilers and Heat Exchangers

Mar 05, 2024

JIS G3461 Standard Boilers and Heat Exchangers

JIS G3461 carbon steel pipes are mainly used for heat exchange inside and outside pipes, such as water pipes, flue gas pipes, superheater pipes, air preheater pipes, etc. Its application areas include: boiler pipes, heat exchanger pipes, and condensers. It can also be used in the chemical and petroleum industries, but cannot be used under low temperature conditions.

Chemical Composition:

Grade	Mfg. Process	Chemical Composition (%)
Grade	Mfg. Process	C	Si	Mn	P	S	Ni	Cr	Mo	Others
STB35	S, E	0.18Max	0.35Max	0.30~0.60	0.035Max	0.035Max	-	-	-	-
STB42	S, E	0.32Max	0.35Max	0.30~0.60	0.035Max	0.035Max	-	-	-	-
STB52	S, E	0.25Max	0.35Max	1.00~1.50	0.035Max	0.035Max	-	-	-	-

Mechanical Properties:

Symbol of class	Tensile strength N/mm2 {kgf/mm2}	Yield point or proof stress N/mm2 {kgf/mm2}	Elongation %
			Outside diameter 20mm or over	Outside diameter 10mm or over to and excl. 10mm	Outside diameter under 10mm
			No. 11 test piece No. 12 test piece	No. 11 test piece	No. 11 test piece
STB340 STB410 STB510	340{35}min. 410{42} min. 510{52} min.	175{18} min. 255{26} min. 295{30} min.	35 min. 25 min. 25 min.	30 min. 20 min. 20 min.	27 min. 17 min. 17 min.

Manufacture Method:

Symbol of class	Heat treatment
Symbol of class	Hot finished seamless steel tube	Cold finished seamless steel tube	Electric resistance welded steel tube other than hot finished or cold finished steel tube	Finished electric resistance welded steel tube	Fold finished electric resistance welded steel tube
STB 340	As manufactured, as required, low temperature annealing or normalizing may be performed.	Low temperature annealing, normalizing or full annealing.	Normalizing	As manufactured. However, as required, low temperature annealing or normalizing may be performed.	Normalizing
STB 410	As manufactured. However, as required, low temperature annealing or normalizing may be performed.	Low temperature annealing, normalizing or full annealing.	Normalizing	Low temperature annealing
STB 510	Normalizing