The differences between Q245R steel and Q345R steel

Q245R steel and Q345R steel are both common steel materials for pressure vessel equipments.

Q245R steel is one of the most widely used container steels in China, and it is as hot as ASTM A516 70 Grade steel and A285C steel. Q245R steel is also becoming more and more popular in the international market. Q245R steel is mainly used to manufacture boilers and pressure vessels in petroleum, chemical, and power plants.

Q345R steel is a combination of 16Mng, 19 Mng and GB6654-1996, and GB150 specified the thickness range is 3 ~ 200mm. Q345R steel contains a certain amount of alloy elements, yield strength tends to be high.

Q345R steel is used in the inner tube of the multi-layer container, for the shell thickness is larger than 36mm for other compression elements (flanges, tube plates and flanges).

Chemical Composition Comparison of Q245R steel and Q345R steel

The table above shows that except for element S and Mn content are different, other elements' limitation of Q245R steel and Q345R steel are the same. For Q345R steel has higher Mn content, its CeQ is 0.1% higher than Q245R steel. Q345R steel notch sensitivity is larger than Q245R steel, low fatigue strength made it easier to produce cracks when welding. So in some application environments, it shall be considered on the medium that can influence these 2 steel types.

Pre: Comprehensive understanding of API 5L X70 steel pipe

Next: Several factors affecting the surface brightness of stainless steel pipe