Q345B round steel strength grade difference

Q345B round steel belongs to low-alloy round steel, also known as 16Mn round steel.


q represents the yield of this material, followed by 345, refers to the yield value of this material, around 345. And as the thickness of the material increases its yield value decreases. Similar to the q235 naming method. Q345a, q345b, q345c, q345d, q345e. This is the distinction of grades, which represent the difference between the temperature of the impact and the difference! Q345a level, is not to impact; q345b level, is the normal temperature impact of 20 degrees; q345c level, 0 degree impact; q345d level, is -20 degree impact; q345e level, is -40 degree impact. At different impact temperatures, the impact value also varies.


Round steel is divided into hot rolling, continuous casting, forging and cold drawing four kinds.

Among them: 5.5-20 mm small round steel is mostly supplied in coils and used as steel bars, bolts and various mechanical parts; round steel larger than 25 mm is mainly used for manufacturing mechanical parts or for making seamless steel tubes.

The specifications for hot-rolled round bars are 12-450 mm.

Continuous casting specifications: 100-800 mm, used for mechanical forging processing.

Forged round steel specifications: 150-1000 mm, used as shafts, flanges, forgings, etc.


Q345B round steel manufacturer: Huaigang Special Steel, Laigang Special Steel, Zhongtian Special Steel, Xining Special Steel, Dongbei Special Steel, Yong Steel Special Steel, Jinan Steel, Handan Iron and Steel, Baosteel Special Steel, Ben Steel Special Steel and other brands .


Wuxi Hongbotai Metal Products Co., Ltd.

Marketing hotline 13861775089

Marketing Hotline 18168397825

Address: No. 168 Qiantang Road, Liangxi District, Wuxi.



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