What is 20g in steel and what is the difference between 20G steel and Q245 material?

20g refers to 20 steel, there are also 20g. A material in steel. It belongs to the boiler plate. G is the first letter of the "pot" in the boiler plate: G. In addition to their carbon content, 20g also has some trace elements.

It is more suitable for use as a boiler and pressure vessel. In addition, 20g also focuses on its physical properties. Such as bending, impact and tensile properties.

<> 20g steel pipes are mainly used in the manufacture of high-pressure and higher-parameter boiler pipe fittings, low-temperature superheaters, reheaters, economizers and water walls, etc.; For example, small-diameter pipes are made of wall temperature 500 heating surface pipes, as well as water-cooled wall pipes, economizer pipes, etc., large-diameter pipes are made of wall temperature 450 steam pipes, headers (economizers, water-cooled walls, low-temperature superheaters and reheater joint boxes), medium temperature 450 pipeline accessories, etc. Since carbon steel will produce graphitization when it runs above 450 degrees Celsius for a long time, it is best to limit the maximum temperature of the pipe as a heating surface to below 450 degrees Celsius for a long time. In this temperature range, the strength of the steel can meet the requirements of superheaters and steam pipelines, and has good oxidation resistance, plastic toughness, welding properties and other cold and hot processing properties are very good, and it is widely used.

The parts used in this steel in the Iranian furnace (referring to a single unit) are the sewer inlet pipe (the quantity is 28 tons), the steam inlet pipe (20 tons), the steam connection pipe (26 tons), the economizer header (8 tons), the desuperheating water system (5 tons), and the rest is used as flat steel and boom material (about 86 tons).

This is the grade in the previous boiler plate standard, and now that standard has been abolished, and the standard of pressure vessel plate is unified, which is the current boiler vessel plate.

The grade in the new standard is Q245R, with a yield strength of 245MPa.

It is a grade of boiler plate, which is rarely used now, and it is an old representation, and now the steel mill uses Q235R, Q345R more. It is generally used in pressure vessels.

20g。The material of carbon steel is mild steel. In the industry, there is a big G and a small G. The big g is 5310, and the small g is 3087

Nothing surprising, and 20 tests are no different. Sensei take 20g too seriously.

Is 20g steel low-alloy steel20g is low-alloy steel, high-quality low-alloy steel mainly includes: weldable high-strength structural steel, general-purpose low-alloy structural steel with a specified yield strength greater than 360MPa and less than 420MPa, such as Q295B, Q345B, Q345C, Q345D, Q345E, Q390A, Q390B, Q390C, Q390D, Q390E, Q390E, Q390E, Q390E; Low-alloy steel for boilers and pressure posture vessels, such as 16mng, 12mng, 15mnvg as specified in GB 713; YB T5139 specified 16mnr; HP295, HP325, HP345, HP365 specified in GB 6653; 16mnr, 15mnvr, 15mnvnr according to GB 6654; 16mn, 15mnv according to GB 6479.

Q245R implements the standard GB713-2008, the old brand is 20G, and it is a steel plate for boilers and pressure vessels. Now 20G and 20R are collectively referred to as Q245R, and Q245R (20G) is specially produced for boilers and pressure vessels, and the special purpose "No. 20 carbon steel". It is much higher than ordinary No. 20 carbon steel.

20R 20G is the previous process standard: GB6654, GB713-86

Q245R is now a new grade, the standard is: GB713-2008

The two are actually the same material, just the name is different.

Q245R boiler pressure vessel steel is a large category of steel plates in boiler plates.

For example: Qu "Chinese Pinyin Qiaoji School first letter. 245—yield strength value. r: The first letter of "Rong" in Chinese pinyin.

It has special ingredients and properties.

It is mainly used as a pressure vessel, and the material of the container plate that should be selected is not the same according to the use, temperature and corrosion resistance.

The delivery status is: hot rolled, controlled rolling, normalizing. Flaw detection is added by the agreement of the supply and demand side.

Such as: 20R, 16Mnr, 14Cr1MOR, 15CrMOR, 09MnNIDR, 12Cr2MO1R, 16Mnr (HIC), 20R (HIC) and so on.

The above are commonly used grades in China; There are also foreign grades, such as: SA516GR60, SA516GR70 and so on.

Niobium, vanadium and titanium elements can be added to Q245R steel, and their content should be filled in the quality certificate, and the sum of the above three elements should not be greater than respectively.

The difference between 20g material and 20 material:

Implement GB699 standard; 20G implements GB713, and the standard is changed to Q245R in 2008.

In addition to the same carbon content of the two, 20g also has some trace elements that are more suitable for use as boilers and pressure vessels. In addition, 20g also focuses on its physical blind combustion performance. Such as bending, impact and tensile properties.

20g than 20 steel has stricter requirements for harmful impurities, internal defects, and inspection standards. That is to say, 20g is specially produced for boilers and pressure vessels, and the special purpose "No. 20 carbon steel".

Chemical Composition: Carbon C:; Silicon si:; Manganese mn:; Sulfur : phosphorus ; p : chromium cr: ; Nickel ni: ; Copper cu: .

20g is one of the materials in steel. It belongs to the boiler plate. g is the first letter of "pot" in the boiler plate:

g。Scope of application: steel plate with a thickness of 6mm-150mm.

Flaw detection standard implementation: JB, divided into three levels. 20g tensile strength, yield strength, elongation after break:

410-550mpa 235-245mpa 20%。

The composition is basically the same, but it is not the same material. 20g is higher than No. 20 steel for impurities, internal defects, and the inspection standard is higher than that of No. 20 carbon steel, and it is stricter than Gaoqingge. That is to say, 20g is specially produced for boilers and pressure vessels, and the special purpose "No. 20 carbon steel".

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