Constructive advice on a different method of pipe connection.

[dmstron]

I have been toying with a different concept for joining pipe conduits. My original objective was to improve on raised face flange connections as they can introduce much stress in the piping system and associated equipment. A typical flex gasket when crushed between faces requires approximately 1/8" of crush. In particular where there may be a series of flanges in a straight run significant stress is introduced. Also if the installers do not pay close attention to bolt torque sequencing much pipe stress distortion can be introduced.
In addition to this and utilizing the concept I have attempted an flex expansion joint.
I have attached some pictures with a brief explanation of the principal. The method of sealling is not really new as it is similar to that used in mechanical seals, floating valve seats, etc... Utilizing media energy to activate a seal force.
I realize there are limitations to where this idea can be adapted to and some further development is required.
Patent rights have been secured. I am however looking for some positve constructive input into how to further take this including any suggestions where can improve. Any assistance will be appreciated.

 

[dmstron]

OOPS! IF INTERESTED TRY THIS LINK. NEW AT THIS.

 

[BigInch]

Looks interesting.

If one of these was installed at one end of a short length of pipe and a normal raised face flange was installed at the other end, would unbolting both flanges allow the pipe to freely drop out of the assembly (without using a spreader)?

Can't see the sealing detail very well. Its a bit small. Can you post a larger diagram of the seal?

What is the exact amount of axial displacement that this flange can accomodate? Would the permissible axial displacement get increase with increasing diameter?

What about a swivel model?

http://virtualpipeline.spaces.msn.com

 

[moltenmetal]

Unless I'm missing something, your design requires/relies on o-rings as part of the overall seal design. That begs the question: why not just machine grooves into the ANSI flange faces and use O-rings instead of using conventional gaskets? This too would get rid of the (perceived) problem associated with gasket crush. That would seem to be a (very) inexpensive alternative to what you're proposing. By the way, the conventional gaskets we typically use do not require nearly as much as 1/8" of "crush" to seal.

Your design may have merit to ease the installation of devices such as level gauges etc. as an alternative to eccentric unions etc.

 

[dmstron]

Hello BigInch, appreciate your interest
The attached should give a larger view of the drawing. Keep in mind the the dimensions don't really mean anything.
In answer to your first question. Partial purpose is to minimize piping stress induced by flange tightening. As well the labor involved when working with pipe flanges is significant. This is trying to address that. With that yes the pipe or piece of equipment or whatever would in essence be a slide in. The floating ring is meant to compensate for any gaps. The amount of allowed compensation is determined by the travel designed into the pocket.
You may question the springs as others have when showed the concept. Spring pressure is required to keep the faces together only when the media pressure s zero.
As using this concept takes away from providing rigid strength other methods of securing would be required.
In case wondering I have bench tested this concept up well over a typical flange rating with finger tight bolting and introducing roughly one degree of face misalignment. No leakage.
You asked about the pipe diameter adaptions. It is basically whatever axial travel want designed into it.
Had not attempted a swivel however probably a good thought.

 

[dmstron]

Thanks for your comments moltenmetal.
I have also wondered why not just use an oring or the like as an alternative to flex gaskets in some installations. This however only addresses part of what trying to achieve. As well depending on the application it may not easy to install such as sliding in a gasket between two faces.
Correct me if I am wrong but part of the reason for using flex gaskets (or spiral wound)is to help take up some of the imperfection in fits. That is why they have the crush.
If you were to look at a typical spiral wound gasket you will see the 1/8" crush. It is not perceived rather witnessed. Don't know your industry however this is typical in the oil industry.

 

[moltenmetal]

The gaskets we're using are pretty much standard spiral wound gaskets. Given that these gaskets start out at ~1/8" thick, 1/32" to 1/16" of crush per gasket is more typical than the 1/8" you talk about.

The "crush" is required to energize the gasket, to force the gasket material into imperfections in the flange faces to make the seal. It does provide some small amount of fit-up tolerance also, but it's a very small amount.

Elastomeric materials are inherently more forgiving of flange surface imperfections and take far less gasket seating stress to seal, but are limited in maximum temperature and the fluids they can handle. You're right about them not being as easy to install as dropping a gasket between flange faces, but the other benefit that o-rings provide is re-use: you don't need to renew the gasket each time you break the joint open.

 

[justinwest]

I like the design. I like to think of flanges as the best device we have, not the best device, for connections.
Hopefully this could be marketed and become available for widespread use.

I just completed a project on natural gas production equipment and during hydro test we found 1 in 5 flangeed connections had to be re-addressed for various issues.
These issues (leaks, misalignment, etc.) had to be taken care of at 11:30 pm. I love nothing more than having leaks keep me from getting to bed the day before we bring a project online!!