Russian heat-resistant steel grade designations
Russian heat-resistant steel grades are identified by their standard designation which represents the tensile strength in kilograms per square millimeter (kgf/mm2). This designation system is well-established and used by Russian steel producers and steel stockholders in various European countries. The tensile strength of a steel grade is generally related to its yield strength, impact strength as well as its general performance capabilities.
Russian heat-resistant steel is a type of steel specially made to tolerate high temperatures and boast high strength, ductility and fatigue strength. It is mainly used in production of heat-resistant components such as boiler tubes and pipes, pressure vessels, motor parts and electric components and welded structures.
Steel grade designations start with a single letter, followed by a two or three-digit number, then two or three letters. The two-digit number indicates the steel grades minimum yield strength. The first letter may be: K (kilogram-force per square millimetre - kgf/mm2) or D (megapascal - MPa) depending on the standards used.
The last two letters identify the type of microstructure obtained from heat treatment. The common types are as follows:
•У – Heat-treated and tempered
•Н – Normalized and tempered
•М – Normalized
•Т – Quench-tempered
•Б - Tempered
•Ф - High temperature tempering
•БР -Tempering and tempering again
For example: 16ХН3СУ is a steel grade with a minimum yield strength of 160 kgf/mm2 which is heat-treated and tempered (У).
In addition, the letter K or D is included in the designation of some steel types. For example: 16KHNH3CU is a high-temperature heat resistant steel with a yield strength of 160 kgf/mm2.
The grades are broken down into several categories based on their chemical composition and mechanical characteristics. They are as follows:
•Carbon, Low Alloy and Tool Steels: They are generally used for construction and engineering purposes. They consist of plain carbon steel, low alloy steels and tool steels which are harder and better wear resistant than plain carbon steels.
•High Strength, Heat Resistant and Special Steels: They are regularly used for power plant and boiler components, pressure vessels, motor components and other heat-resistant parts and assemblies.
•Spring Steel: This type of steel is characterized by its high content of manganese and chromium which makes it particularly suitable for producing springs and other items subjected to high tension.
•Stainless Steels: They are highly corrosion-resistant due to their chromium and nickel content. They are used extensively in cookware, medical and pharmaceutical equipment, chemical processing and architectural applications.
•Heat Resistant Steels: This type of steel is very heat-resistant with its high chromium, molybdenum and tungsten content. It is often used for the manufacture of boilers, heat exchangers and heat-resistant structures.
•High Temperature Alloy Steels: These steels are alloyed with several elements in order to improve their performance at high temperatures. They are used in the manufacture of jet engines, aerospace components and power plant components.
Russian heat-resistant steel is a versatile metal material with a number of applications. It is a common choice for various industries due to its numerous benefits and can easily be machined to achieve specific engineering requirements. With the right grade of steel, your project can be delivered with the highest levels of quality and performance.