CHEMICAL COMPOSITION % max
Steel grade	C	Si	Mn	P	S
STB 340	0.18	0.35	0.30-0.60	0.35	0.35
STB 410	0.32	0.35	0.30-0.80	0.35	0.35
STB 510	0.25	0.35	1.00-1.50	0.35	0.35
Remark: 1. When the purchaser requires product analysis,the permissible deviation for the values given above shall be as specified in the Table in JIS G 032 for the seamless steel tube and likewise in Table 1 (as JIS G 3461)for the electric resistance welded steel tube. 2.Where required by the purchaser,Si may be designated as 0.1-0.35%

MECHANICAL PROPERTIES min
Steel grade	Tensile strength Mpa	Yeild point or proof stress Mpa	Elongation %
STB 340	340	175	35
STB 410	410	255	25
STB 510	510	295	25

Hardness
Steel grade	Rockwell hardness HRB(Mean value of three points)
STB 340	77max
STB 410	79max
STB 510	92max

Heat Treatment (Applicable till the end of 1990)
Steel Grade	Heat Treatment
Steel Grade	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	normalizing
STB 510	normalizing

Please specify the delivery condition and heat treatment requirement when sending the enquiry.

Seamless Carbon JIS G 3461 Steel U Bend Tube For Boiler / Heat Exchanger

Precision Seamless Steel Tubes