JIS G3444 Carbon Steel Pipe for General Structural Purposes
JIS G3444 Structural Steel Pipe Manufacturer
Huayang Steel Pipe manufactures JIS G3444 carbon steel pipes for general structural purposes, providing reliable steel pipe solutions for construction, civil engineering, steel towers, scaffolding, piles, columns, and other structural applications.
JIS G3444 specifies carbon steel pipes used for general structural purposes. The standard covers five grades, including STK290, STK400, STK490, STK500, and STK540, with requirements for chemical composition, tensile strength, yield strength or proof stress, elongation, flattening, bending, dimensions, and manufacturing methods.
Huayang manufactures JIS G3444 structural steel pipes using advanced HFW and ERW technology within its applicable production range. The pipes can be supplied with customized lengths, end conditions, surface treatment, and additional inspection according to project requirements.
JIS G3444 Steel Pipe Product Range
Based on Huayang's current manufacturing capability:
| Product Type | Manufacturing Process | Outside Diameter | Wall Thickness | Length |
|---|---|---|---|---|
| JIS G3444 Structural Steel Pipe | HFW / ERW | Φ48–Φ660.4 mm | 2.0–22 mm | 6–27 m |
For large-diameter structural applications, Huayang can also manufacture applicable structural steel pipes through LSAW technology according to the agreed project specification. However, the applicable manufacturing method and standard designation should be confirmed for each JIS G3444 order.
JIS G3444 Steel Pipe Specification
| Item | Specification |
|---|---|
| Standard | JIS G3444 |
| Standard Name | Carbon Steel Pipes for General Structural Purposes |
| Product | Structural Steel Pipe |
| Steel Grades | STK290, STK400, STK490, STK500, STK540 |
| Manufacturing Process | HFW / ERW |
| Outside Diameter | Φ48–Φ660.4 mm |
| Wall Thickness | 2.0–22 mm |
| Length | 6–27 m or Customized |
| Pipe End | Plain End / Beveled End |
| Surface | Black / Oiled / Coated |
| Application | General Structural Purposes |
JIS G3444 Steel Grades
JIS G3444 classifies structural steel pipes into five grades. STK400 is widely used for general structural members, while STK490 and STK540 provide higher strength for applications requiring greater structural capacity.
| Grade | Minimum Tensile Strength | Minimum Yield Strength / Proof Stress | Typical Application |
|---|---|---|---|
| STK290 | 290 MPa | - | Light Structural Members |
| STK400 | 400 MPa | 235 MPa | General Structural Members |
| STK490 | 490 MPa | 315 MPa | High-Strength Structural Members |
| STK500 | 500 MPa | 355 MPa | Scaffolding and Structural Applications |
| STK540 | 540 MPa | 390 MPa | High-Strength Structural Applications |
The minimum tensile and yield/proof strength values are specified in JIS G3444.
JIS G3444 Size and Dimension Table
The following table shows representative JIS G3444 sizes. The final outside diameter and wall thickness shall be confirmed according to the applicable JIS dimensional table and purchase specification.
| Nominal Size | Outside Diameter mm | Typical Wall Thickness mm |
|---|---|---|
| 15 | 21.7 | 2.0 |
| 20 | 27.2 | 2.0 / 2.3 |
| 25 | 34.0 | 2.3 |
| 32 | 42.7 | 2.3 / 2.5 |
| 40 | 48.6 | 2.3 / 2.5 / 2.8 / 3.2 |
| 50 | 60.5 | 2.3 / 3.2 / 4.0 |
| 65 | 76.3 | 2.8 / 3.2 / 4.0 |
| 80 | 89.1 | 2.8 / 3.2 |
| 90 | 101.6 | 3.2 / 4.0 / 5.0 |
| 100 | 114.3 | 3.2 / 3.5 / 4.5 |
| 125 | 139.8 | 3.6 / 4.0 / 4.5 / 6.0 |
| 150 | 165.2 | 4.5 / 5.0 / 6.0 / 7.1 |
| 200 | 216.3 | 4.5 / 6.0 / 8.0 |
| 250 | 267.4 | 6.0 / 8.0 / 9.3 |
| 300 | 318.5 | 6.0 / 8.0 / 10.3 |
| 350 | 355.6 | 6.0 / 8.0 / 11.1 |
| 400 | 406.4 | 6.0 / 8.0 / 12.7 |
| 450 | 457.2 | 6.0 / 8.0 / 12.7 |
| 500 | 508.0 | 6.0 / 9.5 / 12.7 |
| 550 | 558.8 | 6.0 / 9.5 / 12.7 |
| 600 | 609.6 | 6.0 / 9.5 / 12.7 |
| 650 | 660.4 | 6.0 / 9.5 / 12.7 |
Published JIS G3444 dimensional data include sizes such as 21.7, 27.2, 34.0, 42.7, 48.6, 60.5, 76.3, 89.1, 114.3, 139.8 and 165.2 mm OD, with multiple specified wall thicknesses depending on nominal size.
- The above dimensions are representative sizes. Other outside diameters and wall thicknesses are available according to the applicable standard and project requirements.
Chemical Composition Requirements
JIS G3444 specifies chemical composition requirements according to the selected grade. The main controlled elements include carbon, silicon, manganese, phosphorus, and sulfur.
| Grade | C Max. % | Si Max. % | Mn % | P Max. % | S Max. % |
|---|---|---|---|---|---|
| STK290 | - | - | - | 0.050 | 0.050 |
| STK400 | 0.25 | - | - | 0.040 | 0.040 |
| STK490 | 0.18 | 0.55 | 1.65 | 0.035 | 0.035 |
| STK500 | 0.24 | 0.35 | 0.30–1.30 | 0.040 | 0.040 |
| STK540 | 0.23 | 0.55 | 1.50 | 0.040 | 0.040 |
For STK540 with wall thickness above 12.5 mm, chemical composition may be agreed between the purchaser and manufacturer according to the applicable requirements.
Mechanical Requirements
| Grade | Tensile Strength Min. MPa | Yield Strength / Proof Stress Min. MPa | Weld Tensile Strength Min. MPa |
|---|---|---|---|
| STK290 | 290 | - | 290 |
| STK400 | 400 | 235 | 400 |
| STK490 | 490 | 315 | 490 |
| STK500 | 500 | 355 | 500 |
| STK540 | 540 | 390 | 540 |
For welded structural steel pipe, the applicable weld strength requirements depend on the manufacturing method. JIS G3444 specifies weld tensile strength requirements for automatic arc welded products.
Elongation Requirements
Elongation requirements vary according to the steel grade, outside diameter, wall thickness, specimen type, and manufacturing method.
| Grade | Typical Minimum Elongation |
|---|---|
| STK290 | According to JIS G3444 |
| STK400 | According to JIS G3444 |
| STK490 | According to JIS G3444 |
| STK500 | According to JIS G3444 |
| STK540 | According to JIS G3444 |
Manufacturing Methods
JIS G3444 permits several manufacturing routes, with the applicable combination depending on the product designation.
| Manufacturing Method | Symbol | Description |
|---|---|---|
| Seamless | S | Seamless Manufacturing |
| Electric Resistance Welding | E | ERW Manufacturing |
| Forge Welding | B | Forge Welding |
| Automatic Arc Welding | A | Automatic Arc Welding |
The standard also specifies finishing methods such as hot finishing, cold finishing, and as-welded finishing.
For Huayang's current production capability, HFW/ERW is the principal manufacturing route applicable to JIS G3444 structural steel pipe.
Manufacturing Process
Huayang manufactures JIS G3444 structural steel pipe through controlled HFW/ERW production.
| Production Step | Description |
|---|---|
| Raw Material Inspection | Chemical and Mechanical Verification |
| Coil Preparation | Slitting and Edge Preparation |
| Roll Forming | Precision Forming |
| High Frequency Welding | Longitudinal Weld Formation |
| Weld Bead Removal | Internal and External Scarfing |
| Sizing | Outside Diameter Calibration |
| Straightening | Geometrical Correction |
| Cutting | Fixed or Customized Length |
| Final Inspection | Dimensional and Mechanical Inspection |
Flattening and Bending Requirements
JIS G3444 includes flattening and bending requirements to evaluate the ductility and structural integrity of the steel pipe.
| Test | Requirement |
|---|---|
| Flattening Test | Required according to applicable product conditions |
| Bending Test | Required according to applicable product conditions |
| Bending Angle | 90° where applicable |
| Bend Radius | Grade and product condition dependent |
| Weld Integrity | No harmful cracking or failure |
For example, JIS G3444 specifies flattening requirements using the distance between flat plates, with requirements varying by grade. The standard also specifies a 90° bending test for applicable products.
Dimensional Requirements
Dimensional accuracy is essential for structural assembly, welding, connection, and installation.
| Parameter | Requirement |
|---|---|
| Outside Diameter | According to JIS G3444 |
| Wall Thickness | According to JIS G3444 |
| Length | According to Purchase Specification |
| Straightness | Controlled |
| Pipe End | Square Cut / Beveled End |
| Surface | Free from Defects Detrimental to Practical Use |
The standard specifies manufacturing and finishing conditions as well as dimensional requirements for JIS G3444 structural steel pipe.
Inspection and Testing
Huayang provides comprehensive quality inspection according to JIS G3444 and customer requirements.
| Inspection Item | Test Method |
|---|---|
| Chemical Composition | Spectrometer |
| Tensile Test | Mechanical Testing |
| Yield Strength | Tensile Test |
| Elongation | Tensile Test |
| Flattening Test | Standard Test |
| Bending Test | Standard Test |
| Weld Inspection | Visual Examination |
| Ultrasonic Testing | UT When Required |
| Eddy Current Testing | Available |
| Dimensional Inspection | OD / WT / Length |
| Surface Inspection | Visual Examination |
Surface Treatment and Processing Services
Huayang can provide additional processing and corrosion protection according to project requirements.
| Service | Capability |
|---|---|
| FBE Coating | Available |
| 2PE Coating | Available |
| 3PE Coating | Available |
| 2PP Coating | Available |
| 3PP Coating | Available |
| Internal Epoxy Coating | Available |
| Pipe Cutting | Available |
| Beveling | Available |
| Hydrostatic Testing | Available |
| Customized Processing | Available |
Huayang Anti-corrosion Processing Capacity
| Item | Production Range |
|---|---|
| Outside Diameter | Φ159–Φ1626 mm |
| Wall Thickness | 4–40 mm |
| Length | 8–16 m |
Applications of JIS G3444 Steel Pipe
JIS G3444 steel pipe is designed for general structural applications. The standard specifically covers applications including civil engineering, architecture, steel towers, scaffolding, struts, piles, and other structures.
Typical applications include:
- Building structures
- Steel columns
- Structural frames
- Bridge structures
- Steel towers
- Scaffolding
- Piles
- Supports and struts
- Civil engineering projects
- Industrial structures
STK400 is particularly widely used for general structural members, while STK490 and STK540 are suitable where higher structural strength is required.
JIS G3444 vs JIS G3454
| Item | JIS G3444 | JIS G3454 |
|---|---|---|
| Main Application | General Structural Purposes | Pressure Service |
| Typical Grades | STK290–STK540 | STPG370 / STPG410 |
| Primary Use | Buildings, Structures, Towers, Scaffolding | Pressure Piping |
| Key Properties | Structural Strength and Ductility | Pressure Resistance |
| Main Testing | Tensile, Flattening, Bending | Tensile, Hydrostatic and Other Tests |
| Typical Industry | Construction & Infrastructure | Energy & Process Piping |
Why Choose Huayang JIS G3444 Steel Pipe
| Advantage | Description |
|---|---|
| Standard | JIS G3444 |
| Grades | STK290, STK400, STK490, STK500, STK540 |
| Manufacturing | HFW / ERW |
| Outside Diameter | Φ48–Φ660.4 mm |
| Wall Thickness | 2.0–22 mm |
| Length | 6–27 m |
| Inspection | Mechanical, Dimensional and NDT |
| Surface Treatment | FBE, 2PE, 3PE, 2PP, 3PP |
| Processing | Cutting, Beveling, Hydrostatic Testing |
| Customized Production | Available |
JIS G3444 Structural Steel Pipe from Huayang
Huayang Steel Pipe provides JIS G3444 structural steel pipe for construction, infrastructure, steel towers, scaffolding, piles, columns, and other engineering applications. With HFW/ERW production capabilities covering outside diameters from Φ48 mm to Φ660.4 mm, wall thicknesses from 2.0 mm to 22 mm, and lengths from 6 m to 27 m, Huayang can supply structural steel pipe according to applicable JIS requirements and project specifications.
From raw material inspection and high-frequency welding to dimensional control and final inspection, every production stage is subject to systematic quality control. Additional coating, cutting, beveling, and other processing services can also be provided according to project requirements.