JIS G3462 STBA22 Alloy Steel Seamless Boiler Tubes
JIS G3462 STBA22 Alloy Steel Seamless Tubes JIS G3462 STBA22 Alloy steel boiler and heat exchanger tubes JIS G3462 STBA22 Alloy steel boiler and heat exchanger tubes Quick Details Type:Seamless Steel Pipe. Material: STBA22 Wall thickness(WT)
Description
JIS G3462 STBA22 Alloy Steel Seamless Tubes
JIS G3462 STBA22 Alloy steel boiler and heat exchanger tubes
JIS G3462 STBA22 Alloy steel boiler and heat exchanger tubes Quick Details
Type:Seamless Steel Pipe.
Material: STBA22
Wall thickness(WT): 3.2mm——14 mm.
Outer diameter (OD): 19.05mm——168.3 mm
Length: 6M or specified length as required.
Ends: Plain End, Beveled End, Treaded
Standard: JIS G3462
JIS G3462 Alloy steel boiler and heat exchanger tubes shall be classified into eight grades,STBA22 is a grade of JIS G3462.
JIS G3462 STBA22 Alloy Steel Tubes are mainly used for exchanging heat on within and in the vicinity of the underground. It can use as water tube, smoke tube, superheated tubes, air preheater tube, etc.Higher temperature resistance or capacity corrosion, end up being widely used by petroleum, chemical engineering, boiler, heat exchanger and other power areas.
Method of Manufacture
JIS G3462 STBA22 shall be manufactured by seamless process or by electric resistance welding process
Heat treatments
| grade | Heat treatment |
| STBA 22 | Low temperature annealing, isothermal annealing, full annealing, normalizing or normalizing followed by tempering |
Note: Low temperature annealing shall not be applied to the electric resistance welded steel tube.
Chemical Composition (Unit: %)
| Standard | Grade | Chemical Composition Limits (%) | ||||||
| C | Si | Mn | P | S | Cr | Mo | ||
| JIS G3462 | STBA22 | ≤ 0.15 | ≤ 0.50 | 0.30-0.60 | ≤ 0.035 | ≤ 0.035 | 0.80-1.25 | 0.45-0.65 |
Mechanical Properties
| Grade | Tensile Property (N/mm2) | Yield Point or Yield Strength (N/mm2) | Elongation (%) | ||
| OD ≥ 20 mm | 10 mm ≤ OD ＜20 mm | OD ＜10 mm | |||
| NO. 11 Sample; NO. 12 Sample | NO. 11 Sample | NO. 11 Sample | |||
| Longitudinal | Transverse | Transverse | |||
| STBA22 | ≥ 412 | ≥ 206 | ≥ 30 | ≥ 25 | ≥ 22 |
The dimensional tolerances
(1)The tolerance on the outside diameter of the tube
| Division of outside diameter | Tolerances on outside diamete | |||
| Hot finished seamless steel tube | Cold finished seamless steel tube | Electric resistance welded steel tube other than cold finished | Cold finished electric resistance welded steel tube | |
| Under 25 | +0.4
-0.8 |
【0.10 | 【1.5 | 【0.10 |
| 25 or over to and excl. 40 | 【0.15 | 【0.20 | 【0.15 | |
| 40or over to and excl. 50 | 【0.20 | 【0.25 | 【0.20 | |
| 50 or over to and excl 60 | 【0.25 | 【0.30 | 【0.25 | |
| 60 or over to and excl. 80 | 【0.30 | 【0.40 | 【0.30 | |
| 80 or over to and excl. 100 | 【0.40 | +0.40 | 【0.40 | |
| -0.60 | ||||
| 100 or over to and excl.12 | +0.4
-1.2 |
+0.40 -0.60 |
+0.40 -0.80 |
+0.40 |
| -0.60 | ||||
| 120 or over to and excl.160 | +0.40 -0.80 |
+0.40 -1.00 |
+0.40 | |
| -0.80 | ||||
| 160 or over to and excl.200 | +0.4 | +0.40 | +0.40 | +0.40 |
| -1.8 | -1.20 | -1.20 | -1.20 | |
| 200 or over | +0.4 | +0.40 | +0.40 | +0.40 |
| -2.4 | -1.60 | -1.60 | -1.60 | |
Note:For the tolerances on the outside diameter of electric resistance welded steel tube other than cold finished, if specially required by the purchaser, the tolerances on the outside diameter of cold finished steel tube may substitute.
(2)Tolerances on Wall Thickness and on Thickness Deviation
| Tolerances | Division of wall thickness (mm) |
Division of method of manufacture | Hot finished seamless steel tube | Cold finished seamless steel tube | Electric resistance welded steel tube | |||
| Division of outside diameter (mm) | Under 100 | 100 or over | Under 40 | 40 or over | Under 40 | 40 or over | ||
| Tolerances on wall thickness % | Under 2 | — | — | +0.4mm | +22
0 |
+0.3 | +18
0 |
|
| 0 | 0 | |||||||
| 2 or over to and excl. 2.4 | +40 | — | +20
0 |
+18
0 |
||||
| 0 | ||||||||
| 2.4 or over to or excl. 3.8 | +35 | +35 | ||||||
| 0 | 0 | |||||||
| 3.8 or over to or excl. 4.6 | +33 | +33 | ||||||
| 0 | 0 | |||||||
| 4.6 or over | +28 | +28 | ||||||
| 0 | 0 | |||||||
| Tolerances on thickness disparity % |
— | Within 22.8 of wall thickness | — | — | ||||
Note:The “thickness deviation” means the ratio of the difference between the maximum and the minimum thickness of the wall measured in the same section to the ordered wall thickness and shall not be applied to the tube under 5.6 mm in wall thickness
Testing items:
Chemical Analysis, Tensile Test , Flattening test, Flaring test, Reverse Flattening Test , Hydrostatic Test or Nondestructive Examination.
W=0.2466 t (D-t)
where
W: unit mass of tube(kg/m)
t: wall thickness of tube(mm)
D: outside diameter of tube(mm)