Spacing Between Openings on Pipe Circumference – Limitations?

[nikolastrojman]

Hello everyone,

I’m wondering if there are any standardized limitations regarding the minimum spacing between two openings on the circumference of a pipe. For example we have a 6 inch pipe and we want to put one opening at 0° and the other at 90°.

Are there any references in ASME, EN, or other standards that define how close or far apart such openings should be when positioned around the pipe’s circumference?

If anyone has experience with this or can point me to relevant sources, I’d greatly appreciate it.

Thanks in advance!

 

[XL83NL]

For B31.3 refer to para 304.3.3, which includes a reference to PFI ES-7.

That standard is a recommendation and not a Code requirement.

I think EN 13480 will have similar guidance but probably more prescriptive as it has more rules for a lot more design details than B31.3.

 

[KevinNZ]

See B31.1 clause 104.3.1 (d) (1) (-e)

 

[LittleInch]

How big are the openings?

But I would have said the same thing as Kdvin came out with.

I think this one is like the immortal question about how close can you have two circumferential welds? Plenty of guidance and no "code" requirement.

 

[Krausen]

It can be dependent on reinforcement requirements of your openings. So you need to know your design conditions & understand your reinforcement areas if req'd. But assuming you do not need your openings reinforced, there is no code requirement for minimum spacing btw openings. But typically companies will have minimum spacing standards between welds. If you're welding modern standard carbon steel (e.g. A106B pipe, A105 olets, etc.), you can overlap welds easily in reality without issues with good welding practices. Although this is often looked down on by company standards. This same concept is true with pressure vessels under ASME Section VIII too.