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Japanese JIS Mechanical Structure Steel Designation System
Steel has been used as part of the structure of mechanical structures since the invention of steel. It provides strength, durability, and versatility to a design and is widely used in many industries. In Japan, they have developed a designation system to designate different types of steel and their grades and are known as JIS mechanical structure steel.
The Japanese Industrial Standard (JIS) is the primary standard for mechanical structure steel designation in Japan. It was established in 1918 by the Japanese Ministry of International Trade and Industry (Miti) and is based on the European classified steel designation system. The most common designation for mechanical structure steel is SS, which stands for Structural Steel grades. The SS designations are divided into two sub-groups, SS and SD.
SS grades are used for light structures such as factory buildings, residential buildings, and bridges. SD grades are used for medium and heavy structures such as ships, bridges, and tunnels. JIS mechanical structure steel is designated by four characters representing the grade. The first character is a letter representing the tensile strength, followed by a numerical value that indicates the minimum yield strength. The third and fourth characters represent the type of steel, such as carbon and alloy steel, respectively.
Within each of the two sub-series, there are numerous grades of steel. The most common is SAEJ403, which is used for light structures and has a tensile strength of 80-90 ksi. SAEJ403 is available in different grades such as C, S, and P. The C grade is a low carbon, soft steel and therefore is not suitable for welding or heavy load applications. The S grade is a low carbon medium steel and therefore will provide sufficient strength for light load applications. The P grade is a high-tensile strength steel and is suitable for welding and heavy load applications.
The JIS mechanical structure steel designation system is used by engineers and designers when selecting the appropriate steel for a particular application. It is important to consider the type of application, such as welding or heavy load, when making a decision. It is also important to consider the cost and availability of the steel when making a decision.
Steel is used in a wide variety of mechanical structures in Japan, including bridges, ships, and factories. The JIS mechanical structure steel designated according to European standards is the most commonly used in Japan. It is used to indicate the strength, hardness, and type of the steel that is being used in an application. It is an important tool that engineers and designers use to ensure they are using the right type of steel for the right application.
