2 MTRs Describing two pipe Scheduales S40 and S80 both MTRs same heat and job??

[OBI1INCH]

I was on a project and went to the pipe yard as they had been receiving the 10" S40 Stainless pipe from the mill pretty steadily. I counted 469 pipe received to date.
As I was inspecting them I noticed numerous pipe where .500" wt. (S80 for B3.19). But the pipe was stenciled Sch.40. I wrote the two heat numbers that had .500"wt down and went to review the MTR reports. I found (2) MTR's with same heat number. 1 MTR had in the description Sch.40 and the other had Sch.80!
The second MTR and heat number also had sch.40 but was actually Sch.80! A total of 69 pipe where assigned to these two (or three) MTR reports. When I reported this to my clients they forwarded the report to the supplier and the response was basically no big deal.. I could not believe this client allowed any of this to not have an NCR assigned to show some kind of track record for this supplier. I have never heard or seen this prior to this day.

I am pretty bent out of shape how this was handled because if that is the case why have quality assurance / control at all? What's the point if they are going to let a supplier push out such poor records knowing that the MTRs purpose is to provide a customer with the material's specific chemical and physical properties as well as any required test results to ensure safe application of that material to a specific application believing that the material is what the MTR said it it is in the description?

I had a project a few months earlier with cadmium pipe that came from this same supplier and they had to replace 3 of 10 total pipe inspected. It was 10ttl. 42"OD x 8'L with 32* beveled edges. They where not happy with my decision I'm sure.

What are your thoughts on this?

 

[EdStainless]

It is legal to supply sch80 as sch40.
The real question is to look at the mechanical testing, what size did they test? If they actually just pulled some sch80 that they had on hand to fill the sch40 order that is one thing. But if they are using the same data for multiple sizes then there is an issue.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[fel3]

Depending on circumstances, I might be concerned about the hydraulic differences between the two IDs. If I did these early-on-a-Friday-morning calcs correctly (I assumed water and used Hazen-Willliams), 10" Sch 80 has 114% of the unit head loss of 10" Sch 40 and 112% of the unit minor loss (for fittings). For a short run with few fittings, it won't make a significant difference. However, for a long run and/or lots of fittings and/or perhaps dealing with a pump or pumps, etc., it might be worth another look at the hydraulics is you accept the Sch 80 pipe.

Two years ago I modeled a two-mile long collection header and force main system that connected a dozen groundwater wells to a treatment plant. During the iterative design process, pipe sizes, pipe dimensions ratios (we were using HDPE), and pipe alignments (to a lesser extent) were in a constant state of flux for a variety of reasons. Sometimes the changes didn't affect the hydraulic results enough to worry about and other times they did, including once forcing a change in several of the selected well pumps.

============
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[EdStainless]

I didn't mean to infer that it would work, that is another issue all together.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[Dhurjati Sen]

You have done a great job. Next level is to check the chemical composition by chemical analysis, or at least by PMI and match with MTR. You might have hit something big, like a case of fake MTRs. I have come through such cases almost two decades back in Kuwait.

DHURJATI SEN

 

[gtaw]

Don't get your undies in a bunch. You represent the owner/client. You are their eyes and ears on the site. You observe and report to the client. They make the decision to accept or reject based on your report. You are doing your job if your reports are accurate and the client is informed.

The heat number is traceable back to the melt. Having the same heat number on the CMTR could be that the two sizes were made from material from the same melt. That assumes no mistakes were made at the mill. Mistakes do happen. Sometimes they are mistakes, sometimes that are not mistakes, maybe something worse. My level of concern is dependent on where the pipe was manufactured. Point of information; there is a difference between a CMTR and a MTR. The MTR is a statement that the material provided meets the requirements of X, W, Z with the typical chemistry and mechanical properties. The CMTR is a test report of the actual representative chemistry and mechanicals of the material delivered. A subtle different to some people a major different to others.

At the very least, I agree with Dhurjati, a chemical analysis can be performed to verify it is the right chemistry for the material specified. You could suggest that a chemical analysis would be useful, but that is a decision that needs to be made by your client.

Don't develop the "God Complex", your decisions are not always final. The client usually has the last word because they know more about the application than you. As a matter of fact, my reports use the terms "conforming" and "not conforming". I stopped using the words accept or reject because in my industry, the Engineer has the final say, he determines if it is "good enough", "replace", "rework", or "scrap" the material. The change in terminology may seem minor, but it puts the final responsibility on "accepting" or "rejecting" materials or work back in the lap of the individual that has the ultimate responsibility, i.e., the Engineer representing the Owner. I say the material is "nonconforming", the Engineer says "it's good enough", we aren't in conflict. The Engineer is simply making the decision with regards to how the nonconforming material or work will be deposed.


Best regards - Al

 

[EdStainless]

There had better never be a difference between a 'test report', MTR, or CMTR. They all must accurately describe the material delivered, show all testing needed to comply with the stated specifications, and be traceable to melt.
I don't know of any mill that does not have other process lot designation besides heat.
We require finished product chemistries.
We did a job involving 200T of sheet, and it all had the same heat number. But it was 10 different coils and we got 10 different product chemistries. Of course 8 of those were virtually identical (as we would hope) but it provided one check on the traceability and control.

At some level you need to know the supply chain and how the product got to you. If you don't then it can be very difficult to know what has been done.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed