Expansion joint for above ground pipeline

[happyam]

In order to absorb the thermal expansion of an above ground steel pipe, it is decided to install an expansion joint for the pipe. However, when it comes to the specification of the expansion joint, I don't know how to start. Is there any standard/reference which I could refer to?

Many thanks!

 

[pennpiper]

The best advice I can give you is this.
You say it is an above ground pipeline. You have not given any technical information so it is hard to be real specific with advice but do NOT use and Expansion Joint when an expansion loop or expansion leg will work.

What is the operating temperature?
What is the operating pressure?
What is the commodity?
What is the material?
What is the size of the pipeline?
Do you have two good anchor points for this proposed situation? (An Expansion Joint will not work unless the two end are anchored.)
How long is the run between anchor points?
Is this pipeline insulated?
Where is this pipeline?



prognosis: Lead or Lag

 

[C2it]

Employ an expert. End of story.

A simple error in design or specification of an expansion joint will probably result in failure and a potential disaster.

Google 'Flixborough' for some enlightenment.

 

[C2it]

To contact a recognised expert you could go to Pathway's website at

http://www.myej.com

Go to the "ask the expert" section and send your details.

I recommend sending your question to Dan Edgar.

 

[ramnares]

US Bellows, manufacturer of expansion joints, has a standard procedure for sizing expansion joints in their website catalog.

EJMA - Expansion Joint Manufacturer's Association also has detailed instructions for sizing EJs.

A typical procedure may include the following:
- Calculate thermal expansion of pipe
- Use this as your baseline axial deflection value
- Estimate lateral deflection and angular rotation
- Obtain conversion factor based on number of cycles
- Account for installation misalignment and excursion using appropriate conversion factors.
- Sum values (after applying conversion factor) to get axial, lateral, and rotational deflections and apply further SF is necessary.

 

[happyam]

Thanks so much for all your advice!

The Flixborough incident is really breath-taking. Of course we prefer taking expert's advice for the expansion joint design. I would just like to know more about it. And EJMA really helps a lot.

Again thank you very much for the advices.

 

[rmw]

EJMA has an EJ specification sheet. Fill it out completely. If you don't know enough to fill it out completely you aren't ready to select an expansion joint. When you do get it filled out send it to several vendors and then they will all be bidding apples to apples.

rmw