Issue with calculating the pressure for testing in SW6
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The above are the calculation conditions: the designed pressure inside the tank is -0.1, and that in the jacket is 0.33; the experimental pressure inside the tank is -0.1, with a value of 0.5 for the jacket. Why is only the designed pressure taken into account in the table? Was the experimental pressure not calculated?
This post was last edited by AtlantisH on 2023-4-13 at 15:16. Either the calculated length of the outer pressure cylinder, which is 200 mm, is incorrect, or half of the sum of the calculated lengths of the cylinders on either side of that reinforcement ring, which should be 100 mm, is incorrect. I’m not sure how the reinforcement rings are arranged, but the longest length considered for external pressure calculation is 200 mm; this section must be on one side of one of the reinforcement rings. Is the length considered for external pressure on the other side of that ring 0? SW6 only determines whether its own hydrostatic test is successful or not; it does not consider the stability of the inner cylinder and inner head during the jacket test, which requires separate verification (using the component module to check for pressure differences). The hydrostatic test pressure for the inner cylinder is a minimum of 0.125 MPa, and it is positive pressure.
The maximum spacing for this reinforcement ring is 200, and the software doesn’t calculate based on the experimental pressure, right?
In SW6: The inner cylinder is checked for stress under test conditions based on its test pressure； The jacket has its stress under test conditions checked based on the test pressure applied to it; however, when the jacket is pressurized for testing, the inner cylinder is also subject to external pressure. The stability of this external pressure on the inner cylinder under the jacket’s test conditions, indicated by SW6, is not checked, and it is necessary to verify this using the difference between internal and external pressures in the component module and include the resulting values in the calculation report. Furthermore, SW6 is used only to check the stresses on the cylinder body and head under pressure testing conditions; for components such as flat covers and flanges that require stress evaluation, refer to Section 4.12 of the \"Training Manual for Pressure Vessel Design Engineers – Basic Knowledge and Components\".
Isn’t the calculation of that external pressure cylinder the calculation of the external pressure stress on the inner cylinder under the jacket test conditions?