Fittings are used for the pressure-bearing components of pressure vessels
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For small-scale equipment with a design pressure of 0.5 MPa, can concentric reducing tees be used as a substitute for conical end caps when going from DN250 to DN150? What should I do if I can’t perform the calculations?
No problem – just ensure the wall thickness matches that of the steel pipes at both ends; standard components don’t require a separate calculation sheet.
It must be calculated. Since the calculation method for pipe fittings is not based on GB150, it is equivalent to not carrying out design calculations in accordance with the harmonized standards of the Code for Pressure Vessels. You can use SW6-2011 to calculate the conical section by entering the actual dimensions of the standard parts purchased.
Fittings do not have pressure ratings; concentric reducers can be calculated as conical end fittings, for which the appropriate pipe designation should be selected.
Enter the dimensions of the standard parts into the cone section calculation; as long as the calculation yields satisfactory results, it can be used as a substitute
The large and small ends are reduced versions of conical sections; they fall under the category of standard components, so there are no issues with their calculation
Standard fittings do not indicate the pressure rating. Only wall thickness grade. If selection is desired, calculations must be performed to confirm suitability before use
This post was last edited by wanlirn on 2019-2-23 at 13:16. Calculated based on the folded-cone type end cap; the corner radius R is generally smaller for common pipe fittings than the standard value, and some adjustments need to be made
Personal opinion: Since the angles at which pipes bend are variable, standard calculations are not accurate. However, if we consider the pipes themselves, as long as the thickness of the pipe fittings meets the requirements of the operating conditions, there should be no problem. In this case, as long as the thickness of the cylinder sections at both ends of the pipe meets the requirements under emergency conditions, using pipe fittings with uniform thickness should not pose any safety issues. It’s just that the specific regulations regarding this are unclear; I hope those who are more knowledgeable can provide some answers
There is no calculation document for the elbow fittings on the equipment; it’s not clear whether they are needed on the main body as well.