At first view it seems to be as you interpreted.

But in the same time the i is the one in B31J because "may be considered as more applicable data" so this create confusion.

The intention of the code is shown in S302.6.3 of the same code done by the same members.

The clear intention was to impose the use of B31J as "more applicable data", leaving the code philosophy as it was.
In my humble opinion the phrasing doesn't show this in a straight manner.

Also in B31.1 2020 the appendix D was left inside (apparently without any reason) even the reference is to B31J.

My main problem now is that systems previously analyzed show overstress (SUS and OCC) in some critical points even the modifications are done in other area.

Right now I do not know how to solve this fake overstress. I can not wait for V14. Even if V14 would be out tomorrow let's say, it will take looong time to be used because of inertia. Showing the overstress to the client and trying to explain how the things are in reality is not the best idea.

The overstress is given part because of the mentioned problem, part of the SIF on reducers, also this issue being created by the famous B31J.

I wonder why for "eons" B31.3 considered the reducers being ok without SIF and now this not ok anymore.
One may say that the issues may be solved by a better supporting.
Of course, but this will lead to different configuration respect to the old one.
For example, many times the reducers are placed each side of the control valves.
The heavy valves and the new reducers sif will require additional supports near the valves. This will require some extra space since normally there is a drain that will have to be moved.

Imagine that the modifications will be requested and the senior layout checker will be stunned to hear that what was good for years is not valid anymore. How many times you were told "We have always done like this"

So will be the ability of the stress engineer to explain vs ability of checker to understand why.


Like I said before "better is the enemy of good"

I know that the intention was good.