Fitting damage or defect?

TimmyD

Good Morning! I am a first time poster, mechanical engineer (unlicensed) by trade. We were having some work done on our boiler and the technician found this non-conformity in a ~25 year old fitting. We are replacing, not using, but I have been trying to determine whether this has been a defective fitting that has been in service, or whether there may have been a non-uniformity in the metallurgy that caused erosion? Just curious if anyone has experienced an anomaly like this, and would you replace it? We have already decided this fitting will not go back into service.

Thank you kindly,

Tim

pecmsg

no rust after 25 years of use?

TimmyD

Hi pecmsg,

This is a boiler on a research system, in its life, it has likely run for 0-4 months a year over its life span, and when operating feed water chemistry is being checked daily by a dedicated boiler technician. There was a plug in this port, it was removed for the addition of a high water level switch. This is the actual fitting after the plug was removed, probably for the first time since install.

Thanks,

Tim

EBEBRATT-Ed

I am verry surprised it held water pressure in that condition. I would suspect a water quality issue caused this but then again, I know little about water quality.

I would find it difficult to see how the original installer would install a fitting in that condition so I don't think it would be a defective fitting.

HomerJSmith

I think it was a flaw in the original casting. I don't think the original installer ever inspected the fitting. I do inspect cast iron fittings as I have several times come across fitting that had holes in that you can drive a bus thru. The casting seam seems to be problematic. Quality control is performed by the customer, that's the way it is, especially today.

pecmsg

still NO rust, corrosion?

That fitting looks fairly new.

Intplm.

Dedicated water chemistry is a great deterrent and is, from the surroundings of this anomaly, not the cause.

@EBEBRATT-Ed Surely you installed a fitting without first looking at the thread? I mean, haven't we all?

@TimmyD If you have not cleaned this fitting before taking the picture I would say that this was a fitting/casting defect.

And if not a casting defect from the manufacturer. And you are using this in a "research system" I would also ask if something caustic was eating/dripping on the fitting from the outside causing this decay. I would ask this because, in the picture provided the erosion seems to not come from the inside but from the outside, tapering off as it flows toward the inner part of the fitting.

How did the mail pipe thread look?

HomerJSmith

Look, there would be no leakage in that fitting because the defect is in the hub and the first few threads provided the seal.

mattmia2

Looks like a casting defect. What fitting is that? It looks like it is a reducing cross or something like that that the original fitter probably didn't have another of.

Larry Weingarten

Hi, If there is a name on the fitting, I'd see if I could get in touch with the manufacturer and ask them for their thoughts. Might not be bad to say that you're not looking for warranty 😏

Yours, Larry

mattmia2

i can see where the original installer could have not been looking at it from the right side to see that