seam welded pipe for pressure service
seam welded pipe for pressure service
(OP)
At what size (NPS) is seam welded pipe for pressure service normally installed? (pre-1950s)
The best way to test something is to squeeze it, slowly, until it breaks!





RE: seam welded pipe for pressure service
"What was the maximum size for seamless piping pre-1950 ?"
I do not understank your question...
RE: seam welded pipe for pressure service
Are you asking (?):
Is there a limit on the nominal pipe size for application of seam welded pipe in B31 Pressure piping systems?
Are you asking (?):
Is there a practical limit on the diameter of seamless pressure piping after which seam welded pipe (with appropriate nondestructive examination) should be specified?
What are you asking?
Please try to rephrase your question.
Regards, John
RE: seam welded pipe for pressure service
RE: seam welded pipe for pressure service
I know that today seamless pipe up yo 20 inches in diameter can be procured, but larger than that pipe is rolled and a longitudinal weld seam is formed. piping larger than 30-35 inches may have 2 seams.
I am to evaluate piping that may be 60-80 years old which carries building service steam. Can I expect to see seam welds in piping as small as 12 to 14 inches? "What is the minimum size that I can expect to find seam welds?" is the question I should have asked...
The best way to test something is to squeeze it, slowly, until it breaks!
RE: seam welded pipe for pressure service
It could go either way as seamless pipe has been made for quite some time. As an expedient you could assume that there is a single longitudinal seam weld.
What is the pipe material and what is the temperature and pressure? What kind of assessment are you going to perform? With steam pipe that old you may have asbestos insulation so be careful. Check out the spring hangers too.
You got us curious now
John
RE: seam welded pipe for pressure service
The best way to test something is to squeeze it, slowly, until it breaks!
RE: seam welded pipe for pressure service
Why don't you strip a 360 degree local band of insulation and visually check for seam weld(s)? This is easy enough to do under an asbestos abatement program, and will help in your evaluation of the pipe condition.
RE: seam welded pipe for pressure service
Piping to be assessed ranges in size from 1/2 inch to 54 inches. I know the smaller sizes are socket welds or butt welds and are seamless. The request is that an assessment of 100% the seam welds be made. I am trying to get a handle on the labor estimate to do the NDE.
The best way to test something is to squeeze it, slowly, until it breaks!
RE: seam welded pipe for pressure service
No problem. Select a sampling of the various sized steam lines (start with the 16 to 24" range)and strip a band of insulation to expose the OD surface. If you find a seam weld in this range of pipe diameters, one could assume the larger diameter piping would also be fabricated of rolled and welded plate.
RE: seam welded pipe for pressure service
You WILL have to get a material identification if for no other reason to make a calibration block. Someone is going to have to do a FFS evaluation and knowing the allowable stresses for ALL THE PIPING material will have to be a part of that. Positive material identification will be critical.
I have found that the best way to efficiently examine seam welds in great amounts of piping is the Time of Flight Defraction (ToFD) methodology. Go to this Internet site and watch the vidio:
http:
Nothing commercial here I have no ties to ToFD except I have seen it save a lot of money and do a good job with seam weld examinations in seam welded Hot Reheat Steam Piping systems.
John.
RE: seam welded pipe for pressure service
RE: seam welded pipe for pressure service
RE: seam welded pipe for pressure service
It sounds like you have a lot of practical/field experience to share with regard to piping inspection and older plants.
Is there any book/report/guideline on the inspection of old utility plant systems that has been developed that you could point us toward ?
Anything on the internet..?
Everyting I have found has been on the order of anecdotes, memories and snippets from reports.
-MJC
RE: seam welded pipe for pressure service
RE: seam welded pipe for pressure service
Would your investigation have anything to do with the catostrophic failure of an underground steam heating line in Manhattan? If so good luck!! As I stated before, you will find continuous butt welded pipe [forge welded], ERW pipe, flash welded pipe [AO Smith] and electric fusion welded pipe and some seamless pipe. Many of the circ seams will have been made with the Oxy-fuel gas welding process.
RE: seam welded pipe for pressure service
Regarding asbestos insulation and 1973. Until about 1976 many Owners/Engineers/Architects and US GOV were still specifying asbestos. The Engineering company for which I worked, specifed asbestos in 1973 and 1974 but by 1976 refused to specify for all owners other than the US GOV. Finally, in late 1978, it refused to specify asbestos for US GOV work. Some of the US GOV specs requiring asbestos were still issued after 1981.
RE: seam welded pipe for pressure service
And the rule of thimb for us is... "Test it!" Even if it is yellow or pink. there is such a mix out there that one can not be sure.
As you have pointed out, the year of manufacture is no assurance that it is NOT asbestos.
The best way to test something is to squeeze it, slowly, until it breaks!