Plate without flange 2

[Leo165]

Any other way to install perforated plate without flange in pipe (for better economics)

ahmad

 

[racookpe1978]

Do you ever want to take the plate out again?
Do you ever want to clean the pipe?
Do you EVER anticipate needing to change the plate's pressure drop or nbr of holes?
Why would you NOT want to use two flanges and a plate?

 

[Leo165]

I am working on "cost optimization" of utility units. Low cost process plants, in which water/clean fluids in re-circulation mode are utilized. Answer of first three parts is no (as compromise on accuracy is acceptable/cost savings is research concern). What other installation options can be possible ?? like welding (type/scheme of welding)

 

[bimr]

There is no other method.

If welded inside of a pipe, you would still need a flange or weld to reconnect the pipe.

 

[racookpe1978]

No. The net expense of simply mounting the plate (like a spectacle flange or orifice plate) between two rated flanges is the same expense (or much less!) than "welding a plate somehow" in the middle of a two cut lengths of pressurized process pipe.

 

[LittleInch]

Of course there is. Just get your plate or fabrication made to a bit less than the ID of you pipe, insert it inside then weld up the edge with a fillet weld. Probably best to do this as a pup piece so you can weld both sides or secure it both sides then drop it into the piping system. Basically something like this

https://www.mytub.co.uk/100mm-itron-flow-straightener-product-549579

but without the flanges. You still have two welds, but you don't have the cost and weight of the flanges.

Is it a good idea? That's up to you if you consider the very good points racookpe makes. Any break, blockage or desire to modify the plate then you have to cut it out, but that's your risk.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[StoneCold]

LittleInch
Putting the orifice plate in an existing weld is a great idea. It will be super funny to the next guy who comes along and can't figure out where the pressure drop is coming from, or if you can trick him into pigging the line. Funny to me. Not so much for him. I once spent about a month on the pressure drop of a sieve bed to find out that a tee down stream of the bed had been filled with a metal gauze to make a filter. No indication of it on the outside. That was really funny.

 

[KevinNZ]

Weld it in. Same weld detail each side as a flat head.

 

[LittleInch]

Stonecold - I never said it was a good idea and of course, you need to weld on the outside some sort of plate showing that there is something installed, exactly the same as an orifice plate - it's not always easy to spot those either if someone has cut off the little stub plate that sticks out...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[racookpe1978]

Weld it in. Same weld detail each side as a flat head.

OK, so they do that. Now the two welds are on both sides of the orifice plate? How do you complete the joint while holding the orifice plate between the two sides of the sliced pipe if the orifice plate is the pipe OD? Pipes are not all that thick-walled you know, and the thin pipe wall does not give you the bearing surface to hold back the forces generated by the delta-P required as the purpose of the plate in the first place.

If the Orifice plate exceeds the pipe OD, how do you machine flat the two pipe ends to get two mating surfaces with a weld prep allowing both full-penetration welds at a lower cost than two simple RFSO or RFWN flanges? Do you accept two fillet welds on both sides, relying on the "full it up with weld" fillet welds to prevent fluid loss?

The CONCEPT is bad. Don't do it. Don't accept it.

 

[Leo165]

Respect for all Answers. But I suppose Flanges is not the end. Just for "Think out of the Box" or research approach, we are here to discuss positively so lets do it.
What if orifice is slightly less than Pipe inner dia , then a ring welded on both side/one side of orifice, and then to weld the pipe pieces.

John165