Sockolets on Listed PV 2

[CRG]

An existing 30” diameter, 1.25” t, U stamped vessel needs some 1” sockolets installed for repair/alteration purposes. The purpose of the 1” sockolets is for access to internal non pressure barrier components inside the vessel. A contractor, with R stamp, will make the required modifications to the vessel.

Questions:

Are the installation of 1” sockolets considered a repair or a alteration?

There are already some 2” 3000# sockolets on the vessel. Is there a requirement for additional pressure calculations for the installation of some 1” 3000# sockolets?

For B31 piping code, reinforcement calculations are only required by the manufacturer of the olet because the olet has the integral reinforcement. When using olets on a pressure vessel, how does one determine that the required reinforcement is met for a given vessel design?

 

[metengr]

CRG;
The addition of 1" sockolets on an in-service pressure vessel (i.e., pressure retaining item) is considered a repair under the 2001 National Board Inspection Code (NBIC), 2003 Addendum. If you have 2" 3000# sockolets already installed on the vessel, I see no reason to perform this calculation for a smaller diameter size. The NBIC considers any 2 NPS or smaller penetration in a pressure retaining item a repair, regardless of shell thickness because ASME B&PV code does not typically require reinforcment for openings 2" or under in size.

Sockolets that are purchased to an ANSI standard will have the integral reinforcment necessary for the pressure/temperature rating. The issue of added reinforcment is based on the opening size in the pressure retaining item per the orignal code of construction.

 

[unclesyd]

Just remember to attach the sockolets with the required amount of weld to develop the ratings you need.

 

[GenB]

Still the new opening has to meet any ligaments calc. E if it exist (new opening too close to other openings),
ER

 

[unclesyd]

I forgot to mention that on sockolets you need to get the proper sockolet for the application. You will see this called out in the catalogue as 1" x the pipe dimension of the run or in your case approximating the diameter of the vessel.

http://www.bonneyforge.com/

 

[CRG]

First off, I would like to thank all of you for your comments.

Metengr, you said “The NBIC considers any 2 NPS or smaller penetration in a pressure retaining item a repair, regardless of shell thickness because ASME B&PV code does not typically require reinforcement for openings 2" or under in size.”

Does this mean that it would be possible to drill the vessel and install some 1” NPT plugs? If so, this would simplify the repair and eliminate the need for welding and the associated NDT. These plugs would not be in the vicinity of any other opening. The manufacture did not use any threaded taps in the vessel shell, but instead used threadolets for some 1/2” connections.

At first glance, I did not consider drilling and taping the vessel; however, Metengr’s comment above raises the issue. Are threaded taps in pressure vessel shells allowed? If so, what part of the BPV Section 8 addresses this issue (required calculations, limits to sizes, etc.)?

 

[GenB]

Up to 2in nps if the t of the vessel allows it, see table on min threads/in per size of connection.
ER

 

[GenB]

Up to 2in nps if the t of the vessel allows it, see table on min threads/in per size of connection.
You are still under the NBIC with stamping and inspections.
ER