Is this calculation result wrong?
Thread Content
The inner diameter of the cylinder is DN1000; the design pressure is -0.42 MPa (for the jacketed cylinder), the design temperature is 150°C, the material used is S31603, the corrosion margin is 0.4 (polished surface). The equivalent length under external pressure is 801 mm; these values were calculated using SW6. Is this calculation result contradictory? Design pressure: -0.43 MPa; allowable pressure for the cylinder: -0.4349 MPa. The conclusion is: unqualified. Then it indicates that 1: when the input wall thickness of the cylinder is 8.00, the allowable calculation length is 841.46 ； 2. When the required calculation length is 801.00, the wall thickness of the cylinder needs to be 9.00. It is clearly stated that a thickness of 8 mm is sufficient for an external pressure length of 841, yet it is suggested that a thickness of 9 mm is required when the external pressure is 801.
Internal pressure and external pressure are calculated separately!
This result doesn’t mean that the thickness is insufficient; it means that the length used in your external pressure calculation is too large, and a reinforcement ring needs to be installed.
You didn’t check the calculation results; there’s a contradiction in the results, it’s not an issue with installing reinforcing rings or thickening the cylinder
Results from the latest version of the calculation software. What version of this calculation software do you have?
Upstairs, the diameter you entered differs from that of the original poster; the original poster entered 1100, while you entered 1000.