Jacket equipment: issues related to jacket and cylinder welds
Thread Content
The pressure inside the equipment is 0.3 MPa, while it is 2.5 MPa in the jacket. Is it necessary to use gaskets at the junction between the jacket and the cylinder? Also, is it required to calculate the local stresses in the sealing cone area? What is the most reasonable welding structure?
For further information, the cylinder material is 304, while the jacket material is Q245R.
At the connection between the jacket and the cylinder, gaskets may not be used； Local stress needs to be calculated for the sealing cone section ； There’s nothing special about welded structures either; they can be handled just like regular equipment. The weld coefficient is determined based on the properties of the medium. In short, weld it in the way that is most convenient.
Just choose according to the structure of GB150 appendix
It is not specified whether welding of the same type or different types of steel is involved for 150. Okay, even if I choose 150 and ignore the material issue, what grade is the welding rod? Should full penetration welding be achieved? Is PT testing required, and what is the testing ratio? Also, why can’t I set a shimming plate? Is it because there is no backing plate structure on the 150?
The welds of the pressure vessel shell are all fully penetrated in structure. The electrode grade depends on the material used, and the inspection ratio is determined by you. If RT inspection is not possible, PT or MT can be used. For structures that require shims, you can also choose that option as well. After all, you are the designer, so it’s up to you to make the decisions.
There is nothing reasonable or unreasonable about it; the choice is made based on the processing conditions, testing conditions, as well as the medium, pressure, and temperature of the equipment.
I understand these too; I’m just saying that your reply should follow the structure outlined in 150. I just don’t quite agree with it.
You can also send a picture of the part of the node diagram you designed, so we can discuss it together. As for the structure of Appendix 150, I think it is quite comprehensive and reasonable given our **materials and the level of our craftsmanship. As a pressure vessel designer, it is correct to follow the standards. The operating conditions of pressure vessels are quite complex; it’s better to be cautious, as caution ensures longevity
Go for it, MARK – if I’m in the top ten, I’ll definitely become famous :)
With such high jacket pressure, the inner cylinder must be quite thick; moreover, the stability of the inner cylinder during hydrostatic testing needs to be taken into account