JIS G3101 Standard – Hot Rolled Steels for General Structure
What is JIS G3101 & Hot Rolled Steels?
JJIS G3101 is the Japanese standard for hot-rolled steels. Hot-rolled steels are roll-pressed at temperatures as high as 1700˚F. This process makes the steel easier to form. This standard specifies the hot rolled steel for general purpose structures. There will be other Japanese standards for other types of hot-rolled steels. This blog is about the standard and its various elements.
The Scope of JIS G3101
The JIS G3101 standard specifies hot-rolled steels used in general structures, e.g., ships, rolling stocks, bridges, etc.
JIS G3101 – Material Grades and their Symbols
| Grade Symbol | Steel Product | Dimensions Applicable |
| SS330 | Steel plates, sheets, flats, bars, steel strips in coil | – |
| SS400 | Steel plates, sheets, flats, bars, sections, steel strips in coils | – |
| SS490 | ||
| SS540 | Steel plates, sheets, flats, bars, sections, steel strips in coils | 40 mm or less in thickness |
| Steel bars | 40 mm or less in side length, diameter, or |
Discussion on JIS G3101
The Japanese standards are not only used in Japan but also popularly followed in other countries. There are equivalent American, German, British standards as well. But those do have some variations in terms of grade limits. Japanese standards are popular and widely followed since it offers specific details and grades that are acceptable worldwide. Similarly, many hot rolling companies (even outside Japan) want to have their facilities and processes in accordance with JIS G3101, since it offers them to sell their products with customers who only want material compliant with JIS G3101.
Testing Details in JIS G3101
Chemical Analysis in JIS G3101
General Requirements
The general requirements for chemical analysis shall be given in JIS G0404, Clause 8
Analytical Method
This test method for heat analysis shall be per JIS G0320.
Mechanical Test in JIS G3101
Clauses 7 and 9 of JIS G0404 shall specify general requirements for mechanical testing. The sampling method implied shall be by JIS G0404 Class A, clause 7.6.
The bend test is not necessary to perform. However, it can be performed upon the purchaser’s request.
Hot Rolling Process
Number of Test Pieces for Tensile and Bend Test in JIS G3101
1. Steel Plate and Flat:
The constituents of the test lot shall be a steel product from one lot, and the maximum thickness for the steel product will be under the minimum thickness.
- Two test pieces shall be taken if the mass of Test lot exceeds 50t.
- One test piece shall be taken if the mass of a single steel plate exceeds 50t.2. Steel Coil and Cut-to-Length:
2. Steel Coil and Cut-to-Length
A single test lot shall comprise of steel product from one heat rolled to the same thickness. One test piece is to be taken from each. However, two test pieces shall be taken once the mass of one test lot exceeds 50t.
3. Steel Section
There shall be one heat-rolled section in a test lot, and its maximum thickness shall be under twice the size of minimum thickness. One test piece is to be taken from each. However, two test pieces shall be taken once the mass of one test lot exceeds 50t.
4. Steel Bar:
In a test lot, the maximum diameter of a steel bar from one heat-rolled shall be within twice the minimum diameter. One test piece is to be taken from each. However, two test pieces shall be taken once the mass of one test lot exceeds 50t.
5. Test Pieces for Heat-Treated Product:
The number of test pieces for heat-treated products subjected to heat treatment shall be by points 1), 2), 3), and 4) of this article.
Learn here about JIS G3131 Deep Drawing Quality Hot Rolled SPHE Steels
Manufacturers who comply with JIS G3101
- Aesteiron Steels LLP, bearing contact number +91 22 67776700. Address: g/A, 9th Floor, Mehta Mahal, 15th Mathew Road, Opera House, Charni Road, Mumbai 400004.
- Anson Steel, bearing contact number +86 372 5081703. Address No. 210 Suite B, Huaqiang New Times, Xiange Road, Anyang, Henan, China.
- Kobe Steel Ltd. 2-4, Wakinohama-Kaigandori 2-chome, Chuo-ku, Kobe, Hyogo, 651-8585, Japan
Material Grades is helping manufacturers select the right material by providing them with the main compliance requirements of the JIS G3101 standard. You can also learn more about other Japanese Standard for Comercial Hot-Rolled SPHC Steel, JIS G3131, here.
AboutSyed Hashir Sarfaraz
