pipe 1

[raiders27]

HI everyone!

I looking for mitre elbow, I check two compagnies and the ''a'' mesurement of the elbow is different for the two compagnies. I want to know were I can fin the standard.

Regards.

 

[pennpiper]

In general you do not "Buy" mitre elbows, you fabricate them from pipe at the pipe fabrication shop or at the jobsite.

The basics of a 90 degree Mitre ELL might be:
Two piece/one weld Mitre
or
Three piece/two weld Mitre
or
Four piece/three weld Mitre
etc.

The radius of the 90 degree Mitre can be 1.5 times the nominal pipe size or can be anything you want.

There is no standard that I know of.

 

[vesselfab]

yes 1.5d is kind of standard....but really

now, depending on who you buy them from and how they build them, they can sure get flat spots and mis-matched weld seams.

depending on the service, material, diameter, & thickness, I would look at different type companies

if you have a reasonable amount of straight tangent on the ends, that can be added to the elbow without adding an additional weld.

whole bunch of ways to skin a cat on mitered fittings

 

[jte]

Funny, I was under the impression that mitered elbows had, well two straight tangent sections and no curvy/roundy part.

'Course, this post really should have gone into forum378

jt

 

[vesselfab]

yes they do

but if a mitered ell tangent starting point is a few feet from another seam...you can increase the tangent lenth to include that length thereby ommitting a weld.

rolling offsets...short legs on top of refrac line....a straight run from ell to a flange.

all lend themselves to omitting a weld at the tangent of the ell.


that is if you have someone who is competent at laying out, cutting and rolling the ell miter gores.

the real problems start if the shop does on know the best way to form the gores into pipe after cutting. Rolls form on pressure and the pressure required to form 2'0" long on the short side is less than 4'0" long on the long side.
and staggering seams and...well...the list goes on

I was just warning him about using Joes Welding in a garage.

2 years ago I was neck deep in building vessel replacement sections for a turnaround for a good customer. He came begging us to build a mitered pipe run 72" diameter that was promised to be built by a fabrication shop 1500 miles away out of Hi Alloy Plate using his material. Told him if he had started cutting or rolling we could not help him. Turns out the flat plate was on the floor and he had not started at all and needed the line in 3 weeks. 1 week to get the plate here, laser cut, roll, fit and weld, minor trimming and complete line. we were a few days behind his original need date but we had a greatful client who could not believe it went together so fast and fit like a glove at jobsite.

believe it or not....not all shops are created equal and some old timers have a methods that are long forgotten during the 80's. Remember the 80's? Many people got out of the business and not many fabricators with good reputations are left. Right now many shops around us are laying off and contruction jobs have slowed way down or put on the shelf. We are working most of shop on 2 12 hour shifts, the rest on 2 10 hour shifts 6 days a week. We have a good load of work while others don't.

The only thing we do different is sacrifice profits by working overtime to maintain schedule/delivery. Have an nice looking product with good weld quality. No cheating on weld procedures or required NDE. Our clients know this and this is why they come back to us.

we only use Domestic, Canadian, Western European, or Japanese manufactered product. Don't trust 3rd world material. Only Lincon carbon steel sub-arc wire/flux Kobelco Flux cored wire Lincoln carbon steel stick rods

Stainless steel and non-ferrous alloys we use historically successfull products

NOW I know that there are many GREAT welding products produced around the world, but we have GREAT luck with what we have locally...why change?

I must apologize for writing a novella here, but I just got carried away.

I am sure this engineer can get his mitered ell built just fine.

 

[JStephen]

There is one standard- AWWA C208, applicable to welded steel water lines.

 

[jte]

vesselfab-

Competence???? We don' need no stinking' Competence!

jt

 

[vesselfab]

HA!

I needed a little break of humor this afternoon

How did you know I was a Bogey fan?