The GB/T 713 standard covers a variety of steel plates and steel strips for pressure-bearing equipment, and their chemical composition varies depending on the type and purpose of the steel plate. The following are some common types of steel plates and their main chemical compositions:
Chromium (Cr): It is one of the key components of stainless steel. For example, the "Cr" in 15CrMoR means it contains chromium. The content of chromium is usually within a specific range, such as 12 to 20%. It can react with oxygen to form a dense chromium oxide film to prevent further oxidation reactions, thereby protecting stainless steel from corrosion.
Nickel (Ni): is another important component of 713 stainless steel, its content is usually between 8~10%.
Carbon (C): As a basic element of steel plates, its content is usually controlled at a low level in most steel plates, such as less than 0.03%. But in some specific steel plates, such as 15CrMoR, the carbon content is expressed as 0.15%.
Silicon (Si): It is an important alloying element in 713 stainless steel, its content is usually between 1 and 2%. Silicon increases the strength and wear resistance of stainless steel.
Manganese (Mn): As a trace element in stainless steel, the content of manganese is usually between 1 and 2%. It can also improve the strength and wear resistance of stainless steel.
Phosphorus (P): It is one of the trace elements in 713 stainless steel. Its content is usually less than 0.04%, but during the optimization process of some specific steel plates, the P content may be reduced to 0.025% or less.
Sulfur (S): It is an impurity element in stainless steel, and its content is usually controlled at a low level, such as less than 0.03%.
GB/T 713 "Steel Plate and Steel Strip for Pressure-Containing Equipment" is a comprehensive standard with the following salient features:
1. Multi-part composition: The GB/T 713 standard consists of multiple parts, each of which specifies specific performance requirements and uses in detail. This structure makes the standard more flexible and specific and can better meet the needs of various pressure-bearing equipment.
2. Strictness of technical requirements: This standard has strict requirements on the chemical composition, mechanical properties, and process performance of steel plates and steel strips. These requirements ensure that steel plates and steel strips have excellent quality and can meet the use needs of pressure-bearing equipment in extreme environments such as high pressure, high temperature, and low temperature.
3. Keep pace with the times: With the development of the boiler and pressure vessel industry and the renovation and update of rolling mills, the GB/T 713 standard is also constantly updated and improved. At the same time, the standard also incorporates new steel materials, such as Q420R steel with high strength, high toughness and excellent weldability, and 07Cr2AlMoR steel that is resistant to H2S corrosion, to adapt to changing market demands.
4. Integration with international standards: The GB/T 713 standard referred to advanced international standards during the formulation process, ensuring that the technical level of steel plates and steel strips used in pressure-bearing equipment in my country is in line with international standards.
5. Wide applicability: This standard is applicable to a variety of pressure-bearing equipment, including boilers, pressure vessels, liquefied natural gas (LNG) ships, liquefied petroleum gas (LPG) ships, etc. It regulates the classification, pand, ordering content, size, shape, weight, technical requirements, test methods, inspection rules, packaging, marking and quality certificates of steel plates and strips used in these equipments, ensuring that steel plates and steel strips are manufactured in and consistency and reliability during use.
GB/T 713 "Steel Plate and Steel Strip for Pressure Equipment" has a wide range of applications. It is mainly suitable for the manufacture of boilers, pressure vessels, liquefied natural gas (LNG) ships, liquefied petroleum gas (LPG) ships and other pressure-bearing equipment.
