Piping Class Materials

Where are you Peter? Non-compliance notice should state the Design specs the Contr signed for the work. GC's start your process. The contract has the language.. RFI's?...Change order?..Also figure out why PM is behaving like Lawyer. CYA. More info needed - but Mech eng 101. DOD has a great manual on pissing contests, if you are in the US, check those areas for how to set up your postition. Contact the Field reps for the pipe that is specified but not included in the work.

See CR4 Thread Pound Rating & , also see site ASME B16.5 Flanges

What are the actual pressures and the fluid involved? For example, HP is presumably high pressure, but how high? IP = intermediate pressure (?), and again how high? Class 150 flanges will not handle, say, 600 or 300 psi. Then, if the piping ruptures and injures persons or equipment, whoever signs off on this will have some explaining to do, perhaps in court.

You mention that it is a drain line. So it's not HP. Maybe the contractor is correct, dunno. Is this the right code you are applying? Maybe some more research is required on your end, including reviewing your specifications before you start going any further and creating some enemies.

Perhaps you jumped the gun on issuing the non-conformance prior to doing your homework, and that is why your project engineer wants an interpretation. You should have the codes on hand. Seems we have an acronym for this, if I remember correctly it's RTFM.

It's best to CYA before you do something rather than after, you just might be digging your own grave.

My two cents.

Duane,

Not my area of expertise, but language is.

"You mention that it is a drain line. So it's not HP."

Would you say that a line draining fuel or oxygen from a rocket assembly (Think NASA) is not high pressure just because it's a drain line?

The question is, aside from the original specs and purchase order, just what are these "drain" lines attached to?

j.

Yes, in the context you set it, the drain could be HP. The OP does not state what the application is (I sincerely doubt that it is a rocket assembly, as this question would not likely be posted here).

After posting, I did muse over my own language and should have stated that it is not "likely" to be HP. My response is colored by own experience, where drain lines are not under pressure, or are vented to atmosphere. Perhaps the OP should state what is the purpose, application, or delve into some more detail about the configuration.

Thanks for pointing out the other possibilities, my point is that the contractor is not always wrong. Sometimes it pays to ask the contractor why they did what they did, before issuing stop work orders, requiring reconstruction, demolition, etc. All of which are costly and could come back to haunt you, like in legal action.

The OP wants us to help him cover his ass. I cannot say for sure from the post who is right and who is wrong, can you? So I am pointing out the alternative, that perhaps the contractor may be right. There are some pretty bright contractor's out there who know their stuff, and from the general tone of the post, I am not too sure about the other side of the equation.

Finally, I agree with you that the OP needs to further clarify what is the application, what they are attached to, and where they are draining.

Cheers

There are by the way private entities in the rocket business and plenty of other industrial situations that could set up the same sort of drainage scenario; manufacture and bottling of gases under high pressure for instance.

On the other hand, all other issues aside.

If the specs called for high pressure fitments and the contract as signed called for those high pressure fitments it is not the task of the contractor to provide other than what he contracted to provide.

The fact that there appears to be an internal political problem requires a very simple answer. High pressure fitments were speced and are what we are paying for therefore are what should be supplied, otherwise you (His supervisor) can sign off on this and leave me out of it.

j.

Yes, in the contrived scenario you present, you are correct. Obviously your position is coloured by your experience, just as my position is by my experience. The question is still wide open.

To me, what is still unanswered is why the Project Engineer is not backing up his employee on this issue. This leaves the opening for the alternatives, do you not see this?

Also, if the application is as you point out, then again, I say this would not be posted here. The answer would be quick and to the point - replace it as spec'd. I would also wonder about the quality of contractor selected for such work and the selection process.

Until the OP qualifies his post, I stand behind my answer as entirely plausible (could be wrong, but who could blame me for my interpretation based on incomplete information), with the slight correction to my languaging, as posted prior.

This problem arises from time to time with poorly written spec's and/or communication. You say we spec'd this so we want what we are paying for, and the contractor says, no you did not, the interpretation of the spec is dubious, and we bid on the lower quality item based on the language of the contract. If you want more then it will cost you! Happens all the time, so then the contractor digs in his heels and calls his lawyer or his engineer.

I am always willing to agree to disagree.

cheers

Jack,

This whole thread has been sitting on my mind. After thinking about it further, I think that you are more likely correct about this being an internal political issue. The OP started the process, and likely the Project Engineer is simply requiring him to finish the job with the right paperwork, including citing the applicable sections of the code.

My scenario's are less likely to be correct given the nature of the code cited.

Duane

There is another scenario that in the past I have run across.

Let me just raise the question although we don't know the truth.

What is the difference in value between what was specked and what was installed?

j.

You probably must have entered into a contract with contractor or must have issued PO for the defined scope of work, deviation from this contractual agreement or PO will make the NC valid and binding on the contractor.

Let the project engineer and pres of your company sign off on the install if they think it is ok. Take your name off it.

In my experience, a pipe spec is written after evaluating each component within that spec (pipe, flanges, valves, etc.). Each component is evaluated using the applicable code for that component (B31.3, B16.5, etc.). Typically, you have a chemical engineer and mechanical engineer work together to make a spec for a certain product.

You need to know the design conditions in order to deviate from your spec. It sounds like the spec might have been chosen hastily or without considering the design conditions.

Are you in the inspection group? I would think the project engineer would have to prove to inspections that it is ok to use out of spec components not the other way around.

Hello, you should make your contractor follow what ever spec you gave him to follow when he quoted the job. If he is saying that after the isolation valves he wants to used lower class pipe spec on the open ended drains then you should be the one to figure out if it ok make the call and issue him a new document with a spec. change marked on the low side of the isolation valves. I have seen pipe specs change after valves to drain many times and it is not abnormal to do it as long as the you are certain (and prove it with calculations) that the lower spec. pipe cannot be accidentally over heated or pressurized. On the other if the contractor had the specifications ahead of quoting the job he should have came to you way back and got your approval before he ran a lower spec. pipe. I am not sure you will find anything wrote in stone about whether it is ok to use a lower spec on drain lines in the ASME B31.3 code but you will find information and tools in there or reference to other sections of the ASME codes so you can calculate to if it would be ok in any unique satiation.

pipewelder,

We don't have a lot of information and the OP ought to provide more.

Nonetheless, you know that thing about assumptions, don't you?

How can you assume that a drain line always drains from high pressure to low pressure.

Consider modern refrigeration where we no longer dump refrigerant under pressure into the air, but rather "drain" it into another high pressure vessel.

j.

I not sure how you get me telling him to follow his original spec. or either deciding to change it if it (after doing the appropriate calculations to prove it is safe) is an open drain is assuming anything at all. I think it is up to the OP to see if it is Hp or LP drain and then maybe let us in on the big secret. This way you would not have to assume it is a high pressure drain either. The main point is that it is not uncommon to have a spec. change where an open drain line attaches to an isolation valve on a HP line. I never assumed it was this way but defiantly worth checking to see if it could changed to prevent someone (probably the contractor in this case) from eating the cost of the work that has been already performed.

Too bad the original poster has not clarified this situation. There have been good answers both in defense of the contractor and in defense of the OP's non-compliance notice. But the rest of us don't know whether this is a low-pressure drain to atmosphere, versus a high-pressure drain from one vessel to another. Nothing like a P&ID to detail what the fluid, pressure, and temperature are.

OP = Dilbert?

Project engineer = pointy-haired boss or bean-counter?

Contractor = Mario Brothers?

Where's Alice to do the actual calculations?

You are 100% correct in writing the non conformance if the contractor is running pipe out of spec. Working as a project engineer by day and then being on the contractor side of things in the evenings at my pipe fabrication shop I see this from both sides. I know that there can be some pretty aggravating engineers that will not budge one bit on anything even as small as minute details. With this being said there are also some very aggravating and slick contractors out there trying to save a dime on anything they can. One thing I would say is to be sure to go back and read the spec. and review your P and Id flow sheets and be sure of what you are doing before costing the contractor and the guy you are working for a ton of money and/or embarrassment. I say this because the contractor has probably read it 100 times to see if he is right and if there are any potential extra work opportunities in the scope or specifications. It is in a way our own fault for beating down contractor prices over the years. i has gotten to the point of contractors bidding jobs so low they know they won't make much if any profit but just keep their employee base working and paid till a better job comes along. You need to be ready to back your decisions with proof before even mentioning it to your boss. Also I think your boss should never tell you to prove your statement in front of the contractor because it is a very difficult thing to regain the contractors respect when/if a boss overrules your decision and sides with the contractor in case you missed something.

Good luck!

The same your post #4 at Pipe Wall Thickness and post #11 at Arabian Heavy Crude and Flow Rate .