Calculation of non-standard supports
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This post was last edited by bingo242 on 2018-1-19 at 22:17. It deals with a horizontal tank with a diameter of DN640×8, whose end cap is a welded flat cover. The current supports are of a non-standard type (as shown in the figure below). Initially, it was planned to carry out non-standard calculations in accordance with NB/T47042, but according to that standard, the support angle ranges from 120° to 180°. I would like to ask everyone how this can be calculated
If the pressure is low, no calculation is needed; if the pressure is high, increase the angle to 120.
The design pressure is 2.0 MPa; the special inspection agency requires calculations for the supports. How is this calculated?
Why not choose standard supports?
Please handle the calculation of the base plate with expertise. I believe the allowable load for angle steel can be calculated as follows: take min(critical pressure, product of the cross-sectional area of the angle steel and the allowable stress of the angle steel material). The method for calculating the critical pressure is based on the section on rod stability in \"Mechanics of Materials\", namely Pcr=π^2EI/(μl)^2; angle steel can be considered as a structure with fixed supports at both ends.
The casing is designed in accordance with national standards. I originally wanted to design the feet myself, but the foreigners insisted on using their designs, as it’s more convenient for them
Give priority to using standard saddles; even if they are not available, opt for sizes that are permitted by the standards. For example, when it comes to the wrap angle, there is no need to use a 180° angle
National standard bearings should be given priority, as they are safe and convenient.
For foreign-funded projects, only the standards of the owner’s company are usually allowed to be used, and the calculations are generally carried out through internal analyses
Due to the non-standard saddle, coefficients K1 and K2 cannot be found for calculating the axial stress at the lowest point of the saddle’s plane; K5 is also unavailable for calculating the circumferential stress of the cylinder, and K9 cannot be used for calculating the horizontal component of the stress on the web. Therefore, conventional calculation methods cannot be applied for the stress analysis of this saddle, and stress analysis must be used instead.