Q345 seamless pipe is a low alloy series ---- low alloy high strength structural steel (GB/T1591-1994). Q345A, B, C, D, E is the representative grade of this kind of steel, of which A, B steel is usually called 16Mn, this material is the most common; Q represents the yield of this material, and the 345 behind refers to the yield value of this material, which is about 345.

Chemical composition(%):

Q345A seamless pipe mechanical properties:

Tensile strength: 490-675MPa, yield strength: ≥345MPa, elongation: ≥ 21%

Q345B seamless pipe mechanical properties:

Tensile strength: 490-675MPa, yield strength: ≥345MPa, elongation: ≥21%

Q345C seamless pipe mechanical properties:

Tensile strength: 490-675MPa, yield strength: ≥345MPa, elongation: ≥22%

Q345D seamless pipe mechanical properties:

Tensile strength: 490-675MPa, yield strength: ≥345MPa, elongation: ≥22%

Q345E seamless pipe mechanical properties:

Tensile strength: 490-675MPa, yield strength: ≥345MPa, elongation: ≥22%

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Q355 is a type of steel. It is a kind of low-alloy high-strength structural steel, widely used in Bridges, vehicles, ships, buildings, pressure vessels, special equipment, etc., where "Q" means yield strength, 355 means that the yield strength of this steel is 355MPa, and will reduce its yield value as the thickness of the material increases.

Chemical composition(%):

Yield strength(Mpa):

Tensile strength (Mpa) : 450-630.

Impact test (temperature: 0℃) : longitudinal ≥34J, transverse ≥27J

Elongation (%) : ≥21