Has anyone here ever heard of such pipe. I build custom tanks and 1 of my customers is demanding a couple 4" sch. 20 steel pipe nipples t.o.e. on the tank. I told the customer there is no such pipe and best I could do is sch. 40 if they want threaded or sch. 10 if they want flanged or roll grooved. They say they have this pipe at there fabrication shop and I am wrong in stateing that it is not an available pipe size. In my years of dealing with pipe to the best of my knowledge 4" pipe goes sch. 5, 10, 40, 80, and bigger. Am I correct or has someone on the boards actually seen it in sch. 20. Even if there was a sch.20 it would be impossible to thread it correct, too thin of wall, as they tell me there's is threaded(npt).
You're not even supposed to thread sch 40 if it's got to handle pressure.......
In my Pipe Fitters Manual, 4" pipe is available in Sch.5, 10, 40 & 80, just as you said. I saw no sch. 20.
Bob
Do they make it? Probably so. We have 4" distribution and transmission piping that is 4" .156 wt and 4" .219 wt. Sch. 10 is listed at .120 and sch. 40 .237 wt. I had some welders go to Iowa where they welded on some 4" .188 wt I "believe", it may have been 6". These are API 5L. Threaded? It used to be in the day, we no longer put in couplings and fully enclose any older ones when located. I would have to believe somewhere they still manufacture these to meet certain applications.
I'm sure they make it, but I'm also sure that it's for an entirely different application. I'd be willing to bet that whoever you talked to really thinks that 1/8" wall pipe is sch20. This last bid job I'm doing was the same deal. The "engineers" wanted certain diameters of pipe at a certain thickness. After coming in more than 30 grand above their budget, they finally started listening to me when I told them what sizes were domestic and cost a hell of a lot less.
Sometimes I could cringe, but I have learned to assert myself at the risk of not getting the job. It has payed, because people respect that. They can see that you know what you're talking about. Although, some people are absolutely stubborn. These people often fail getting quality work, because they won't listen to you........
Depends on if you are starving or not, BUT - Suggest using 40 or 80 collars/nipples, if he doesn't do it - he'll have you back to fix it right later.......
Just tell them if they will supply the nipple's that they say they have you'd be glade to install them. You know in a polite manner.
I've checked into the applicable standards, and in fact, the minimum size of Sch. 20 carbon steel pipe is 8 inches in diameter. So, 4 inches carbon steel, Sch 20 pipe definetely doesn't exist.
Now, as jarsanb suggests, turbolaser's client might be thinking of an API 5L pipe. In this case, the client is wrong, because API 5L pipe isn't classified by Schedule numbers but by the outside diameter and wall thickness.
Milton's suggestion is a good one. If you follow it, turbolaser, then let us know what your client thinks a 4 inches Sch 20 pipe is. We're awful curious to know.
Giovanni S. Crisi
Sao Paulo - Brazil
Well they have say that they will send me enough nipple to do there 2 tanks. I can't wait untill they arrive so I can see what it is for myself. I will let you all know what the pipe size turns out to be when it arrives at my shop. Thanks for all the replies.
Betcha a case of beer that it exists....
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