47065.3-2018 Allowable stress of ear bearing body material
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In NB/T 47065.3-2018 ear-type bearing preparation instructions, 4.1 b) mentions that when the ear-type bearing body material is Q235B, the allowable force is 200MPa, as long as the ear-type bearing is selected according to the properties of the steel structure member. Please help. How is this 200MPa calculated? In which standard can it be seen?
NB/T 47065.3-2018 has stipulated that the author can follow this choice. The specific calculation is generally obtained by dividing the yield strength of the material by the safety factor.
When the material of the support is Q345R,... calculate the allowable stress of the support body. . .
When the material of the support is Q345R,... calculate the allowable stress of the support body. . .
The calculation methods for each part of the ear-type bearing are different. You can list the calculation book for everyone to see. The rib plate is a bending member, so the stability coefficient needs to be considered. As mentioned in NB/T47065-2018, it is reduced according to 50017. The obtained allowable compressive stress is much smaller than the calculation method of 47003.1-2009. You can try it
Looking at the picture, I don’t know how I got the allowable force of Q235B = 200MPa. If I change the material of Q235B to Q345R, what should the allowable stress of the support body be equal to?
Where did you see that the allowable stress of Q235B is 200 MPa?
This post was last edited by 511948814 on 2019-7-15 14:57. Look at the picture, use SW6 to calculate the support, use the standard support, the stiffener material is Q235B, and the given allowable stress is 200.
This post was last edited by FMSD on 2019-7-16 10:53 This is how I understand it: 1. First calculate the strength of each part according to the specification. If it fails, you can modify the size and thickness of the support. Generally speaking, there is a margin in the design. It is impossible to completely determine the size and thickness of the support based on the allowable stress. ； 2. The question you raised is of certain significance. You can contact the editor to have a look.
Q345R is definitely higher than Q235B. I don’t know but I’ll calculate it at 200. I can’t lose much money on carbon steel.
If the slenderness ratio of the ear bearing is ≥120 [Euler's formula for slender rods], the load-bearing capacity will be the same [because the elastic modulus of steel is the same, only when it is <120, changing the material is effective].