2" 150# LWN thickness?

[koplan]

Dear, everybody!!!
I found the the property of 2" LWN size someting wrong as follows.
Please review the database.
=================================================
per ANSI;
OD = 3.25"82.55mm), ID=2" (50.8mm), thickness = 0.625" (15.875mm)
per Compress;
OD = 77.72 mm, ID = 50.8 mm, thickness = 13.46 mm

 

[vesselfab]

FVC and others

use a o.d. of barrrel of 3.063

 

[Christine74]

There are a few slight differences in LWN thicknesses depending upon the manufacturer.

The Taylor Forge dimensions don't always match the Forged Vessel Connection dimensions, which in turn may not match the Lenape Forge dimensions.

-Christine

 

[unclesyd]

Recalled from memory.
There is a fairly large tolerance allowed in the barrel and bore dimensions. This tolerance is a give and take as the minimum wall thickness has to be maintained.

Even though we tried to stay with one manufacturer the fitters were always to check the OD to provide the basis for fit up.

For calculations we had an in house generated table that conformed to several manufacturer's specifications within codes limits.

 

[TomBarsh]

ASME standard B16.5 addresses "weld neck flanges" (WNF) as well as other flange configurations. But it does not address "long weld neck flanges" (LWNF).

The neck dimensions of long weld neck flanges are established by each flange manufacturer. There is some consistency in dimensions among manufacturers but this is not guaranteed.

COMPRESS applies the dimensions of long weld neck flanges produced by Forged Vessel Connections, Inc ("FVC"). However, the input fields for the neck dimensions (diameter and wall thickness) are unlocked and may be edited by the designer if the dimensions do not match the desired dimensions.


Tom Barsh
Codeware Technical Support

 

[jte]

Tom-

Perhaps it is time to add "Straight Hub Welding Flanges" to the database in Compress. These were added into ASME B16.5 with the 2003 edition. See 2.8 on page 3 and Fig. 15 (see link). These look like LWN's to me; hopefully we can begin to get the fabricators to meet the standard.

jt