For container equipment at 400°C, what factors need to be considered in material selection and design?
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bk14.jpg For container equipment designed for a temperature of 400°C, what factors need to be considered in material selection and design, and what issues should be taken into account? Carbon steel, for general steam heating equipment, diameter DN400, pressure 1.0 MPa, horizontal type? https://attach01.hcbbs.com/forum/201811/14/124952ieb7b07bso9mjee0.png
This post was last edited by jizhanwei22 on 2018-11-16 at 12:37. As specified in the conditions, the carbon steel plates that can be used for this container shell are Q245R and Q345R. 1. With a design temperature of 400°C, the Q235 series of steel plates were excluded first. 2. When using Q245R, there are no restrictions; it can be designed in accordance with relevant standards. 3. When using Q345R, when calculating the hydraulic test pressure, the allowable stress value should be taken from the side closest to the left of the thick line, namely 143 MPa. Of course, since the inner diameter of the container is DN400, GB/T8163 steel pipes can also be used, such as 10#, 20#, and Q345D steel pipes. It should be noted that their thickness must not exceed 10 mm, and the limits on the sulfur and phosphorus content of the steel pipes to be used should be specified in the drawings. When pipes are used for pressure vessel shells, it should also be noted that their mechanical properties need to be retested. See the screenshot for details.
Where is the source for that third point, and what exactly is shown in the screenshot? :handshake
It wasn’t included the first time; it’s added now
Source: GB150-2011, Note 3 to 4.6.2.2. This is because the allowable stress value to the right of the thick line in the allowable stress table is determined by the permanent strength, and note 3 requires that the allowable stress shall not be lower than the minimum allowable stress values determined by the yield strength and tensile strength.
The screenshot represents the standards set by the Ministry of Chemical Industry; there is no need to comply with them if they are not referenced in the drawings.