JIS G3445 Carbon Steel Tubes For Machine Structural Purposes
JIS G3445 Carbon steel tubes for machine structural purposes
JIS G3445 Carbon steel tubes Quick Details
Company Name: Beite steel pipe
Country/Region: China
Material：STKM11A, STKM12A, STKM12B, STKM12C, STKM13A, STKM13B, STKM14A, STKM14B, STKM16C ,STKM20A , etc
FOB Price: US $1200-2200 / Ton | 1 Ton/Tons (Min. Order)
Port of Shipment：Tianjin,China
Payment：L/C or T/T
Delivery: 7-15 days after payment
Package：Standard export package,suit for all kinds of transport, or as required
JIS G3445 Carbon steel tubes Dimensional Range & Specification
Outside Diameter：12.7mm——323.8mm
Wall thickness：3.0mm——12.7mm
Length：6000mm、12000m or specified length as required.
JIS G3445 Carbon steel tubes
Scope
This JIS G3445 Standard specifies the carbon steel tubes, hereinafter referred to as the "tubes", used for machinery, automobiles, bicycles, furniture, appliances and other machine parts.
Main Grade:STKM13A, STKM13B , etc
The subclassification letter symbols A, B and C are used to indicate distinction of method of manufacturing the tube, cold working process, heat treatment, etc
Method of Manufacture
The tubes of Grades 13 shall be manufactured by seamless process, electric resistance welding process, or butt welding process,
The tube shall be as manufactured or as cold-finished condition, or they shall be subjected to appropriate heat treatment.
Chemical Composition of JIS G3445
|
Standard
|
Grade |
Chemical Composition |
|||
|
C |
Si |
Mn |
P、S |
||
|
JIS G3445 |
STKM13A |
≤0.25 |
≤0.35 |
≤0.60 |
≤0.040 |
|
STKM13B |
≤0.25 |
≤0.35 |
≤0.60 |
≤0.040 |
|
Mechanical Properties of JIS G3445
|
Standard
|
Grade |
Tenslle Strength(MPa) |
Yield Strength(MPa) |
Elongation(%) |
|
JIS G3445 |
STKM13A |
≥375 |
≥215 |
≥30 |
|
STKM13B |
≥440 |
≥305 |
≥20 |
Appearance
The tubes shall be practically straight. and the two ends shall be at right angles to the axis of the tube.
The tubes shall be free from defects detrimental to practical use.
The surface finish of the tubes
Dimensional Tolerances
The tolerances on outside diameter and wall thickness for the tubes
Tolerances on Outside Diameter
| Division | Tolerances on outside diameter |
| No. 1 |
Under 50mm 【0.5mm 50mm or over 【1% |
| No. 2 |
Under 50mm 【0.25mm 50mm or over 【0.5% |
| No. 3 |
Under 25mm 【0.12mm 25mm or over to and excl. 40mm 【0.15mm 40mm or over to and excl. 50mm 【0.18mm 50mm or over to and excl. 60mm 【0.20mm 60mm or over to and excl. 70mm 【0.23mm 70mm or over to and excl. 80mm 【0.25mm 80mm or over to and excl. 90mm 【0.30mm 90mm or over to and excl.100mm 【0.40mm 100mm or over 【0.50% |
Remarks
1.For hot finished seamless steel tube, the outside diameter tolerances No. 1 shall be applied.
2.The tolerances on outside diameter of quenched and tempered tubes shall be as agreed upon by the purchaser and the manufacturer.
Tolerances on Wall Thickness
| Division | Tolerances on wall thickness |
| No. 1 | Under 4mm +0.6mm -0.5mm |
| 4mm or over +15% -12.5% | |
| No. 2 | Under 3mm 【0.3mm |
| 3mm or over 【10% | |
| No. 3 | Under 2mm 【0.15mm |
| 2mm or over 【8% |
Remarks
For hot finished seamless steel tubes the tolerances NO. 1 shall be applied
Test
Chemical Analysis
Tensile Test
Bending Test
Flattening Test
Marking
Each tube having passed the inspection shall be legibly marked with the following items, the order of arranging the items is not specified.
However, for smaller tubes or on a request from the purchaser, tubes may be bundled together and marked for each bundle by suitable means.
(1) Designation of grade
(2) Letter symbol indicating the manufacturing process(¹)
Note (1)
The letter symbol indicating the manufacturing process shall be as follows.
However, the sign may be replaced by a blank
Hot finished seamless steel tube -S-H
Cold finished seamless steel tube -S-C
Electric resistance welded steel tube other -E-G
than hot finished or cold finished ones
Hot finished electric resistance welded steel tube -E-H
Cold finished electric resistance welded steel tube -B
Cold finished butt-welded steel tube -B-C