Ed,

First, I apologize for using the word overstess (I meant to say overload) in the first paragraph of my post.

Second, I have no reason to disregard your judgment in specific cases; in fact I would tend to trust it based on your many posts here.

Third, I would expect that you, personally, seldom see cases where pump overloads exist in the run/stop cases. I would expect that because you are a veteran hand at this. You doubtless build in what your experience tells you is sufficient flexibility for multiple pump or compressor systems from day 1, and so you avoid most of your later problems.

Fourth, I agree 100% that when rotating equipment allowable loads are the issue, they are MUCH more restrictive than the Code stresses.

But you have to remember, probably 90% of the readers of this forum are young, and don't have the kind of experience that you and I have. I don't think it's prudent to tell them that things like this can be hand-waved away.

Run/stop loads for rotating equipment are some of the most important and difficult things that we do, and to try to give new hands the idea that it is otherwise is very misleading. I have seldom been in an operating powerplant or refinery where they didn't have a pump somewhere having new bearings or seals installed, most likely because some analyst years ago didn't think the run/stop load cases were worth worrying about.

Many of the old hands here, especially including me, are stunned that so many young people are trying to learn this discipline on their own. I estimate that fewer than 5% of those who do not have a senior engineer readily available as a mentor will be in this business five years from now, either out of frustration or as a consequence of their having overlooked something that causes a major problem. I, for one, regard my role here as trying to guide the newbies through the minefield of things not explicitly covered by the piping Codes.