20G boiler plate

20G steel is a boiler plate.

G is the first letter of the "pot" in the boiler plate: g. In addition to the same carbon content, 20g has some trace elements that are more suitable for use in boilers and pressure vessels.

In addition, 20g also focuses on assessing its physical properties. Such as bending, impact and tensile properties.

Executive standard: GB713-1997 (both internal and external standards implement this standard)
Scope of application: steel plates with a thickness of 6mm-150mm.
Because the steel plate is delivered with a positive tolerance when it is delivered, there is also a thickness added value table for the boiler plate. When calculating the weight of the steel plate theoretically, it is necessary to add the corresponding value on the table on the basis of the thickness.
On request, the steel plate can be delivered by heat treatment: controlled rolling, normalizing, etc.
Flaw detection standard implementation: JB/T4730.3-2005, divided into three levels.

20G steel composition:
C——(0.17～0.24)%
Si——(0.17～0.37)%
Mn——(0.35～0.65)%
P——≤0.040%
S——≤0.040%

Yield point σ^s - not less than 250MPa
Tensile strength σ^b——not less than 420MPa
Elongation δ————Not less than 25%
Section shrinkage ψ————not less than 55%
Impact toughness a^K - none
Hardness HBS - hot rolled steel 156

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