Pressure Class Designations for forged steel Socket Weld Fittings

[JC44]

Can anyone tell me if socket weld fittings are available in Class 150? ASME B31.3 references B16.11 for socket weld fittings. This standard covers CL3000, 6000, and 9000 fittings. I've been asked to specify class 150 fittings to reduce cost on a project, but I've searched the internet and can't find a supplier for them which leads me to believe they are either very uncommon or actually don't even exist. Any help would be appreciated.

JC44

 

[unclesyd]

As far I I'm aware of nothing exist under Class 2000 except some Classes called out for exotic alloys.
Class 2000 is called out for Sch 40 as the bores will
match.
The Class designates the maximum non-shock pressure at ambient temperature.

You will find threaded in Class 2000,3000,6000.
Socket weld in Class 3000,6000,9000, and some 10,000.

Forged steel fittings are about the lowest cost fitting around and are off the shelf.

Our last big project used around 2500 forged socket weld fittings (Class 3000).

 

[FIF99]

Hi,

For our classes we always specify Class 3000 SW or Thrd fittings as per ASME B16.11 in ASME 150# pipe classes.

Success.
Regards, FKE

 

[BigInch]

Don't you mean working pressure rating rather than "Class", as used in reference to "ANSI Class, ANSI#150, ANSI#300, etc."?

I thought Socket/Thread-o-lets are designated by a working pressure rating, as in "3000#" where "#" means LBS/IN^2 not "#" as in "Class, ANSI".

BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com

 

[unclesyd]

In the B16.11 call out of Class 2000, etc, the number is the actual guaranteed working pressure at ambient temperature. You will notice from the following Penn Machine charts that the pressure rating is reduced as the temperature rises above ambient.
I would always purchase forged steel fittings based on the B16.11 Class numbers.

http://www.pennusa.com/pennpage/directory/catalog/nonshocktempchart.html

Ambient is defined as: A place where the naked human body can exist for several hours with very little discomfort.

 

[JLSeagull]

Only this week I was marking a vendor drawing regarding the fittings shown as Class 3000. I thought that she was confused with ASME B16.5 flange classes. However, I checked ASME B16.11 and the nomenclature is Class 3000.
Think ASME not ANSI. Think Class 3000 not 3000 #. I just love having desktop access to download the current standards.

 

[pipingdesigner]

JLS, correct!

It's very important to use the correct standards, these will guide you as to the required nomenclature.

The ASME B16.5 - 1996 Pipe Flanges and Flange Fittings
This standard covers pressure-temperature ratings, materials, dimensions, tolerances, marking, testing, and methods of designating openings for pipe flanges and flanged fittings.

The standard includes flanges with rating class designations 150, 300, 400, 600, 900, 1500, and 2500 in sizes NPS 1/2 through NPS 24, with requirements given in both metric and U.S units.

The Standard is limited to flanges and flanged fittings made from cast or forged materials, and blind flanges and certain reducing flanges made from cast, forged, or plate materials.

Also included in this Standard are requirements and recommendations regarding flange bolting, flange gaskets, and flange joints.

ASME/ANSI B16.11 - 2001 - Forged Steel Fittings, Socket-Welding and Threaded
This Standard covers ratings, dimensions, tolerances, marking and material requirements for forged fittings, both socket-welding and threaded.



pipingdesigner

http://www.pipingdesigners.com

 

[BigInch]

JLS,
Now we know who to aks!

BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com

 

[JC44]

Thanks for the input folks. I did find a supplier for Class 150 socket weld fittings, so they do exist just not to an ASME standard. They are covered in an MSS standard # SP-114.

 

[unclesyd]

The SP-114 fittings are CRA alloys not forged steel.

They normally met the B16.11 Spec as Class 1000.

Be careful as some imports in this "specification" are no up to par.

 

[moltenmetal]

I've never seen 150# SW fittings in anything other than cast stainless grades. I've also heard of, but not seen, the forged equivalents of these which meet the B16.11 1000# class.

I'd take unclesyd's suspicions about these fittings very seriously.

Since you're only using them up to 2" anyway (right?), is there really all that much money to be saved on the fittings versus going with the readily available 3000# stuff? I hate to see material going to waste as much as the next guy (probably moreso), but I must concede that sometimes an over-spec'd standard material is better than a rare "optimum" one.

 

[JC44]

I appreciate the input, molten. The fittings that I have found are cast as you mention. I have heard warnings of foreign pipe & fittings before and agree it must be seriously considered. You are correct in that these will be would be used on small bore pipe. The project I'm working on is fairly significant in size (my guesstimate of 1200-1600 small bore fittings), so any little bit will help on tight budget. Also considering press-fit but I have no experience with them so I have a bit of studying to do.

 

[unclesyd]

I don't know if this is one of your sources for the Class 1000 or the Sp-114 CRA fittings but here is a good supplier.

With your quantity you still might be able to get in on a price break despite the current supply problem.

http://www.alloystainless.com/index.html