Operating temperature of Q235B vertical dome storage tanks
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Help, please! Our company has a vertical circular dome storage tank with a capacity of 200 cubic meters; its diameter is 6600 mm and its height is 7000 mm. The material used is Q235B, with a wall thickness of 6 mm. We plan to use this tank to store a medium at a temperature of 250°C, with a density of 1.03 g/cm3. I would like to ask the experts whether this is feasible Meanwhile, the tank foundation consists of asphalt sand laid on a concrete base; can this foundation withstand such temperatures?
First, determine the standards applicable to the container. Due to its poor material properties, Q235 material is not a steel suitable for use in containers. During the revision of GB/T150-2011, some experts called for the removal of this steel grade. Considering use in larger, less critical applications, the standard retains the two grades Q235B and Q235C (Materials Section: Appendix D); the allowable stress values for these steels have been reduced by means of quality factors. The standard indicates that the operating temperature for Q235B is 20–300°C, but it should be noted that the allowable stress values specified must be strictly followed for verification.
GB 50341-2014 Code for Design of Vertical Cylindrical Welded Steel Oil Tanks – tanks operating at atmospheric pressure are designed in accordance with this standard
What medium was originally stored? What medium is it now? Will there be a vapor pressure at 250°C? If there is work pressure, it is necessary to assess its intensity ； If the working pressure exceeds 0.1 MPa, it becomes a pressure vessel, and the use of such a tank is not permitted. If all of the above are met, and without considering a corrosion allowance, this tank can be used. However, since the medium temperature exceeds 90°C, thermal insulation pads must be installed on the concrete foundation.
The GB/T50341 design standard is adopted, meeting the requirements of its Appendix C, namely the design temperature can reach 250 degrees
Can the foundation adapt to this temperature? What does it mean? Someone from the civil engineering structure field should answer
250°C – not afraid of the asphalt sand melting it?