JIS G3445

JIS G3445 Steel Pipe

JIS G3445 is a Japanese standard that specifies the requirements for carbon steel tubes used in machinery, equipment, automobiles, bicycles, furniture, appliances, and other mechanical parts. These tubes are not just any regular tubes; they are meticulously designed for machine structural purposes. The seamless pipes under this standard are widely utilized in various industries, including nuclear devices, gas, petrochemical, shipbuilding, and boiler industries. The production process of these tubes ensures that they meet the highest standards set by the Japanese Industrial Standards (JIS), making them reliable and efficient for any mechanical application.

JIS G3445 Specification

Our JIS G3445 carbon steel tubes are available in various steel grades, dimensions, and production procedures. They come with different surface coatings, end types, and joint methods, and offer machining services. The manufacturing methods include Hot Finished Seamless, Cold Finished Seamless, ERW Steel Tube, and Butt-welded Steel Tube. With such diversity in production methods and specifications, we ensure that our clients receive products tailored to their specific needs.

Production Standard	JIS3445
Manufacturing Processes	BW ERW SMLS
Outside Diameter	DN25 – DN500
Wall Thickness	3mm – 18mm
Pipe Length	specific random
Steel Grade	STKM11A、STKM12(A,B,C)、STKM13(A,B,C)、STKM14(A,B,C)，STKM15(A,C)，STKM16(A,C)， STKM17(A,C)，STKM18(A,B,C) STKM19(A,C) STKM20A
Corrosion Prevention	Lacquer, Varnish, Oiling, Galvanizing
End Processes	Square Cut, Bevelling, Threading, Socket
Further Processing	Welding, Bending, Hole Drilling, Punching, Swaging, Tapering, Flaring, Expanding

JIS G3445 Dimension Table

Our JIS G3445 tubes come in a range of outer diameters from 19.05mm to 630mm and wall thicknesses from 2.0mm to 14mm. Usually agreed between the purchaser and the manufacturer. With such a wide range of dimensions, we cater to various industries and applications, ensuring that our clients always find the perfect fit for their projects.

Chemical Requirements of JIS G3445

The chemical composition of our tubes is strictly controlled to ensure high-quality steel. Elements like carbon, silicon, manganese, sulfur, and phosphorus are kept within specified limits, ensuring the tubes’ durability and efficiency.

Grade		Symbol of Grade	C	Si	Mn	P	S	Nb or V
Grade 11	A	STKM11A	0.12 max.	0.35 max.	0.60 max.	0.040 max.	0.040 max.	–
Grade 12	A	STKM12A	0.20 max.	0.35 max.	0.60 max.	0.040 max.	0.040 max.	–
	B	STKM12B
	C	STKM12C
Grade 13	A	STKM13A	0.25 max.	0.35 max.	0.30 to 0.90	0.040 max.	0.040 max.	–
	B	STKM13B
	C	STKM13C
Grade 14	A	STKM14A	0.30 max.	0.35 max.	0.30 to 1.00	0.040 max.	0.040 max.	–
	B	STKM14B
	C	STKM14C
Grade 15	A	STKM15A	0.25 to 0.35	0.35 max.	0.30 to 1.00	0.040 max.	0.040 max.	–
Grade 15	C	STKM15C	0.25 to 0.35	0.35 max.	0.30 to 1.00	0.040 max.	0.040 max.	–
Grade 16	A	STKM16A	0.35 to 0.45	0.40 max.	0.40 to 1.00	0.040 max.	0.040 max.	–
Grade 16	C	STKM16C	0.35 to 0.45	0.40 max.	0.40 to 1.00	0.040 max.	0.040 max.	–
Grade 17	A	STKM17A	0.45 to 0.55	0.40 max.	0.40 to 1.00	0.040 max.	0.040 max.	–
Grade 17	C	STKM17C	0.45 to 0.55	0.40 max.	0.40 to 1.00	0.040 max.	0.040 max.	–
Grade 18	A	STKM18A	0.18 max.	0.55 max.	1.50 max.	0.040 max.	0.040 max.	–
	B	STKM18B
	C	STKM18C
Grade 19	A	STKM19A	0.25 max.	0.55 max.	1.50 max.	0.040 max.	0.040 max.	–
Grade 19	C	STKM19C	0.25 max.	0.55 max.	1.50 max.	0.040 max.	0.040 max.	–
Grade 20	A	STKM20A	0.25 max.	0.55 max.	1.60 max.	0.040 max.	0.040 max.	0.15 max.

Mechanical Requirements of JIS G3445

Our tubes are tested for their mechanical properties, ensuring they meet the required tensile strength, yield strength, and elongation percentages. This ensures that our tubes can withstand the toughest conditions and deliver optimal performance.

Grade		Symbol of Grade	Tensile Strength N/mm2	Yield Point or Proof Stress N/mm2	Elongation %		Flattening	Bendability
Grade		Symbol of Grade	Tensile Strength N/mm2	Yield Point or Proof Stress N/mm2	No.11 Test Piece No.12 Test Piece，tube axis direction	No.Test Piece，perpendicular to tube axis	Distance between flat plates	Bend Angle	Inside radius
Grade 11	A	STKM11A	290 min.	–	35 min.	30 min.	1/2 D	180°	4 D
Grade 12	A	STKM12A	340 min.	175 min.	35 min.	30 min.	2/3 D	90°	6 D
	B	STKM12B	390 min.	275 min.	25 min.	20 min.	2/3 D	90°	6 D
	C	STKM12C	470 min.	355 min.	20 min.	15 min.	–	–	–
Grade 13	A	STKM13A	370 min.	215 min.	30 min.	25 min.	2/3 D	90°	6 D
	B	STKM13B	440 min.	305 min.	20 min.	15 min.	3/4 D	90°	6 D
	C	STKM13C	510 min.	380 min.	15 min.	10 min.	–	–	–
Grade 14	A	STKM14A	410 min.	245 min.	25 min.	20 min.	3/4 D	90°	6 D
	B	STKM14B	500 min.	355 min.	15 min.	10 min.	7/8 D	90°	8 D
	C	STKM14C	550 min.	410 min.	15 min.	10 min.	–	–	–
Grade 15	A	STKM15A	470 min.	275 min.	22 min.	17 min.	3/4 D	90°	6 D
Grade 15	C	STKM15C	580 min.	430 min.	12 min.	7 min.	–	–	–
Grade 16	A	STKM16A	510 min.	325 min.	20 min.	15 min.	7/8 D	90°	8 D
Grade 16	C	STKM16C	620 min.	460 min.	12 min.	7 min.	–	–	–
Grade 17	A	STKM17A	550 min.	345 min.	20 min.	15 min.	7/8 D	90°	8 D
Grade 17	C	STKM17C	650 min.	480 min.	10 min.	5 min.	–	–	–
Grade 18	A	STKM18A	440 min.	275 min.	25 min.	20 min.	7/8 D	90°	6 D
	B	STKM18B	490 min.	315 min.	23 min.	18 min.	7/8 D	90°	8 D
	C	STKM18C	510 min.	380 min.	15 min.	10 min.	–	–	–
Grade 19	A	STKM19A	490 min.	315 min.	23 min.	18 min.	7/8 D	90°	6 D
Grade 19	C	STKM19C	550 min.	410 min.	15 min.	10 min.	–	–	–
Grade 20	A	STKM20A	540 min.	390 min.	23 min.	18 min.	7/8 D	90°	6 D

Steel Grades in JIS G3445

We offer JIS G3445 tubes in various steel grades, including STKM11A, STKM12(A,B,C), STKM13(A,B,C), STKM14(A,B,C), and up to STKM20(A, B, C). Each grade has its unique properties, ensuring that our clients can choose the one that best fits their requirements.