JIS G3444 Steel Pipe

Pandapipe manufactures JIS G3444 structural steel pipes in strict compliance with JIS G3444 standard specifications to ensure that the steel pipe products produced have the best performance and quality.

JIS G3444

We use superior manufacturing processes to ensure the structural integrity and durability of steel pipes. Through JIS G3444 international standards and certification, can support three-party inspection, you can rest assured to get our products, it not only has strict quality control, but also peace of mind after-sales service.

JIS G3444 PDF Download

JIS G3444 Specification

JIS G3444 structural steel pipes manufactured by Pandapipe have a comprehensive specification covering dimensions, manufacturing processes, steel grades, surface coatings, end types, joint methods and machining services.
JIS G3444 structural steel pipes we provide are flat, inclined, threaded and other end types and pipe fittings, flanges, joints and other joint methods.
In addition, we are able to provide you with machining services to meet the exact specifications of your project.

Standard	JIS G 3444
Procedure	SMLS ERW SAWL SAWH
Dimensions	21.7-1016.0mm
Thickness	2.0-22mm
Unit Length	3-18m
Steel Grade	STK290	STK 500
	STK 400	STK 540
	STK 490	–
Surface Coating	Black lacquer coating,Varnishing, Oiling, Hot Dip Galvanizing
	FBE, 2PP, 3PP, 2PE, 3PE
End Type	Plain, Bevelled, Threaded, Grooved，Shouldered
Joint Method	Fitting, Flange, Coupling, Clamp, Pipe Shoulder, Welding
Pipe Machining	Welding, Bending, Hole Drilling, Punching, Swaging, Tapering, Flaring, Expanding

Steel Grades of JIS G3444 Steel Pipes

JIS G3444 steel pipes are designed for general structural purposes and are widely used in various construction and engineering applications. These pipes are classified into several grades, including STK290, STK400, and STK490, each indicating the minimum tensile strength of the steel in megapascals (MPa). The STK290 grade is known for its basic strength and versatility, while STK400 and STK490 provide higher strength levels, making them suitable for more demanding structural projects. Each grade ensures reliable performance and durability, meeting the specific requirements of diverse construction needs.

JIS G3444 Dimension Table

Pandapipe offers JIS G3444 steel pipe products in a wide range of outside diameters, wall thicknesses and lengths. And flexibility to customize services. Among them, the outer diameter covers 21.7mm to 1016mm. The wall thickness of the steel pipe is carefully calibrated to balance strength and flexibility.
The following JIS G3444 Dimension Table is provided for your reference and help.

JIS G3444 Steel Pipe Size Chart

Outside Diameter mm	Wall Thickness mm
21.7	2
27.2	2	2.3
34	2.3
42.7	2.3	2.5
48.6	2.3	2.5	2.8	3.2
60.5	2.3	3.2	4
76.3	2.8	3.2	4
89.1	2.8	3.2
101.6	3.2	4	5
114.3	3.2	3.5	4.5
139.8	3.6	4	4.5	6
165.2	4.5	5	6	7.1
190.7	4.5	5.3	6	7	8.2
216.3	4.5	5.8	6	7	8	8.2
267.4	6	6.6	7	8	9	9.3
318.5	6	6.9	8	9	10.3
355.6	6.4	7.9	9	9.5	12	12.7
406.4	7.9	9	9.5	12	12.7	16	19
457.2	9	9.5	12	12.7	16	19
500	9	12	14
508	7.9	9	9.5	12	12.7	14	16	19	22
558.8	9	12	16	19	22
600	9	12	14	16
609.6	9	9.5	12	12.7	14	16	19	22
700	9	12	14	16
711.2	9	12	14	16	19	22
812.8	9	12	14	16	19	22
914.4	12	14	16	19	22
1016	12	14	16	19	22

Production Tolerance of JIS G3444

JIS G3444 specification of production tolerances for steel pipe products is essential to ensure product quality, consistency and acceptability. These specifications usually cover the outside diameter, wall thickness, length and quality of the pipe.

Classification	Tolerances on wall thickness
Classification	Seamless steel tube	Other than seamless steel tube
Class 1	＜ 4mm +0.6mm -0.5mm ≥4mm +15% -12.5%	＜ 4mm +0.6mm -0.5mm ≥4mm +15% -12.5% ＜ 12mm -12.5% ≥12mm +15% -1.5mm
Class 2	＜ 3mm[0.3% ≥3mm [10%	＜ 3mm [0.3% ≥3mm [10% ＜ 12mm[10% ≥12mm +10% -1.2mm

Chemical Requirements of JIS G3444

JIS G3444 manufactured by Pandapipe uses steel with the right chemical composition to provide strength, durability and corrosion resistance. Its chemical composition includes elements such as carbon, manganese, phosphorus, sulfur and silicon.

At Pandapipe, every element of our products is carefully controlled to provide you with exceptional quality and performance.

Chemical Composition Unit：%
Symbol of Grade	C	Si	Mn	P	S
STK290	–	–	–	0.050 max.	0.050 max.
STK400	0.25 max.	–	–	0.040 max.	0.040 max.
STK490	0.18 max.	0.55 max.	1.65 max.	0.035 max.	0.035 max.
STK500	0.24 max.	0.35 max.	0.30 to 1.30	0.040 max.	0.040 max.
STK540	0.23 max.	0.55 max.	1.50 max.	0.040 max.	0.040 max.

Mechanical Requirements of JIS G3444

JIS G3444 We produce for different steel grades of steel pipe tensile strength, yield strength, weld tensile strength, flattening resistance and bending are to be precisely tested. The resulting product has good ductility and can be bent and formed without cracking. It is also durable and flexible.

Symbol of Grade	Tensile Strength N/mm2	Yield Point or Proof Stress N/mm2	Weld Tensile Strength N/mm2	Flattening Resistance	Bendability
	Tensile Strength N/mm2	Yield Point or Proof Stress N/mm2	Weld Tensile Strength N/mm2	Distance Between Flat Plates（H）	Bending Angle	Inside Radius
	Applicable Outside Diameter
	All Outside Diameters	All Outside Diameters	All Outside Diameters	All Outside Diameters	50 mm or under
STK290	290 min.	–	290 min.	2/3 D	90°	6 D
STK400	400 min.	235 min.	400 min.	2/3 D	90°	6 D
STK490	490 min.	315 min.	490 min.	7/8 D	90°	6 D
STK500	500 min.	355 min.	500 min.	7/8 D	90°	6 D
STK540	540 min.	390 min.	540 min.	7/8 D	90°	6 D
NOTE 1 In this table，D stands for the outside diameter of tube.

Application of JIS G3444

JIS G3444 steel has been widely used in many fields.

Bridge engineering: Some steel grades of JIS G3444 have good strength and stiffness. Suitable for building bridge components such as beams, piers and abutments.

Building construction: Applied to frame systems, roof structures and facades.

Industrial applications: General JIS G3444 steel pipes are used to build support structures, conveying systems and equipment frames.