off spec piping

[mariolucas75]

Dear forum,

There is a vessel constructed to an ASMVE VII div 1 code (At least as datasheet says).
Vessel nozzle spec says: 4", wall thickness 1.305"

But, in schedule table there is no 4" pipe having thickness 1.305".
Maximum thickness for 4" pipe is 0.674" = 17.12mm (XXS).

Having done physical measurements: ID ~97mm / 3.81"
OD ~ 163,24mm / 6.42""

If the vessel is constructed to an ASME should not it have an ASME compliant piping ? Is it kind of some off spec piping (some custom piping) ?

 

[LittleInch]

Looks like someone did a typo on the 4inch and meant 6 inch?

But that is gun barrel stuff. What sort of pressure is this?

If it has a signed off form (A1?) then see what it says.

But yes you can have custom piping.

 

[mariolucas75]

Design pressure is 14 bar....
Even if it is a typo 6 " also would not have that thickness...

Suppose it is a "gun barrel" or "heavy bore" piping - is there some kind of standard for such thick "things" ?

 

[GBTorpenhow]

Its not pipe, the nozzle is a heavy barrel long welding neck.

Class 150 Standard Connections Flanges Archives - Texas Flange

Texas Flange's Class 150 LWN Flanges, designed for long weld neck standard connections, offering strength and reliability in lower pressure environments.

www.texasflange.com

 

[LittleInch]

Even heavy barrel doesn't match the OPs physical measurements, which would work if this was a 4" nozzle, but looks like a 6 inch nozzle, with 4" HB ID.

At thise sizes, the physical strength aspect would have more of an impact.

 

[GBTorpenhow]

measurements match a 4" 150 HB LWN almost exactly...?

 

[LittleInch]

measurements match a 4" 150 HB LWN almost exactly...?

ID Yes, ("Having done physical measurements: ID ~97mm / 3.81"")

OD- No, ("OD ~ 163,24mm / 6.42""")

 

[GBTorpenhow]

You might be looking at the wrong column, 4"-150 HB OD is 6.44"

 

[LittleInch]

You might be looking at the wrong column, 4"-150 HB OD is 6.44"

Fair enough - I was looking at the bore for the others.

That really is gun barrel stuff though for 14 bar DP.

 

[GD2]

Dear forum,

There is a vessel constructed to an ASMVE VII div 1 code (At least as datasheet says).
Vessel nozzle spec says: 4", wall thickness 1.305"

But, in schedule table there is no 4" pipe having thickness 1.305".
Maximum thickness for 4" pipe is 0.674" = 17.12mm (XXS).

Having done physical measurements: ID ~97mm / 3.81"
OD ~ 163,24mm / 6.42""

If the vessel is constructed to an ASME should not it have an ASME compliant piping ? Is it kind of some off spec piping (some custom piping) ?

Why do you say the nozzle has to be from a pipe? As long as it meets the acceptable material by the Code, it can be fabricated by other methods too.