When the cone calculation determines the required length for the cylinder reinforcement section, can the high-neck flange be considered as the length of the cylinder reinforcement section?

It is not permissible when the allowable stress of the flange material differs significantly from that of the cone material.

In my personal opinion, 1) it is difficult to weld directly to the flange. Since the stress at the conical section is very high, the same is true for the flange; it is best to add a straight section before welding. 2) It needs to be calculated to determine whether it can serve as a support line; those that pass the calculation can be used as support lines.

I have two questions below: 1. Can a cone be connected directly to a high-neck flange? (It can be achieved in manufacturing.) 2. When the cone calculation indicates a required length for the cylinder reinforcement section, can the high-neck flange be considered as part of this reinforcement section length, thereby assuming that the length of the cone’s cylinder reinforcement section meets the requirements? (No, first of all, the connection method used is welding. When the flange neck is welded to the cone, the strength at the weld site is higher than that of the base material. Although its physical and chemical properties meet the standard requirements, when subjected to external forces, deformation of the neck occurs later than at the weld site. Once deformation occurs, the weld site becomes a critical section, which can even lead to leaks.) *It is more or less equivalent to the function of an expansion joint in thermal pipelines*)

I hope more people will join in to continue the discussion

The first one is okay, the second one is not

Answer 1: Yes, it’s possible. 2. We will only use the actual length – as long as is truly necessary. . .