Using DN325 pipes to make DN426 elbows?
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Today, I saw on the material certificate for a elbow that there was an elbow with a 1.5D 90-degree bend; the specifications for the raw material were 325*18, yet it was used to create a seamless elbow with dimensions of 426*18. When I asked the manufacturer, they said that this process is possible. Is that true? Are not the same specifications used to manufacture elbows? How to ensure the thickness remains unchanged when turning a small tube into a large one? ? ? Has anyone seen it? Thank you!
Construction shall be carried out in accordance with the drawings, which serve as the guiding document; all actions must comply with the terms of the contract. In case of any conflicts with the design drawings, the design institute must issue a design change order; otherwise, nothing will be considered valid.
I was wondering if such a technique exists? It has nothing to do with design
Is it possible that the design is wrong? It’s better to check it
I’ve never seen this type of design. Most of the times it’s done to save materials, or due to purchasing errors, for convenience on site. . . . . It’s done for the sake of ease of experimentation.
It’s stated on a material certificate sent to me by the manufacturer; it has nothing to do with the design, I think
One popular process for manufacturing bent pipes is expansion bending and shaping, but the thickness of the tube blank must be greater than that of the wall of the elbow produced by this method.
Is it an error in the material certificate issued by the manufacturer? They issue certificates casually – didn’t they see this mistake?
Haven’t seen it. Thinking in another way, has there been any change in the amount of steel used, the weight of the elbows, and the volume they occupy?
The thickness is definitely thin, but the minimum wall thickness is 0.875 of the nominal thickness; it’s not clear whether the wall thickness after expansion will meet the requirements
Convert it to see if, in theory, the target is reached; if not, it becomes unexplainable. If it is achieved, find a few points and measure the thickness.