distance of the flange to the vessel at inside projection 1

[John_123]

Hi, newbie on this industry. Would you mine asking a help/advise if there's a standard way of determining the minimum distance of the flange to the vessel wall inside of the vessel. Although it would depend on the flange size vs vessel ID size, but a guiding parameter/number as rule of thumb would be enough. Thanks

 

[r6155]

As little as possible.

Regards

 

[david339933]

I would go at least the value of A3 in UG-37 to take full advantage for reinforcement. You made need more projection to weld the flange properly.

 

[SnTMan]

John_123, I am a little confused by your terminology, but I'd offer a couple of things:

Further to david339933's comment I'd add, pay attention to the limits of reinforcement normal to the vessel wall. See UG-40(c). Also pay attention to UG-40(e) regarding flange materisl contributing to reinforcement.

A good practice, sometimes required by client specs, is to provide sufficient projection such that flange bolting can be removed from the backside of the flange without disturbing (removing) vessel insulation, if present. If all nozzles are set to a common projection (fairiy common) then the largest nozzle typically sets projection for all.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[r6155]

Ummm!
First weld the flange to the pipe (automatic welding if possible) and then to the vessel. It is better to welding from the inside (if possible).
For manhole the same alignment is not necessary with other connections, it must be as small as possible to facilitate access and egress.

Regards.

 

[John_123]

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This is what I mean. Thanks for all of your tips/advices

 

[SnTMan]

Well that sure would have been helpful at the start

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[SnTMan]

Observe the limits of reinforcement as applicable, make sure you can make the welds, make sure you can get tools (including hands) in place to make up the joint. Should do it

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[r6155]

If the nozzle has a reinforcing pad (see UG-37) the pneumatic test must be inspected inside the vessel. The flange can make it difficult to inspect for possible leaks and the need for repair.

Regards