anchoring pipeline

[B.L.Smith]

Dear Friend,

I have some questions about anchoring of a pipeline, that I've mentioned bellow:
1- where in pipeline anchor support should be considered in a pipeline which in buried in some portions of its route and is aboveground in some others?
2- I'm working on a pipeline which a line break valve is buried and 20 meter after the valve this pipeline is aboveground. Should I consider a anchor near the buried line break valves because of its movement?(as you know it is located on unrestricted area and movement of the line is considerable.)

Sincerely

 

[LittleInch]

your best option is not to have any anchors at all and let the pipeline move the few mm it needs. Each pipeline is different and you've not given much information (line size, change of temperature, lengths buried / above ground) so it's difficult/impossible to see your particular example.

Also I'm working on the basis that this is a fully welded line - push fit water lines are different...

I don't understand your last comment about movement of lines is considerable. What do you consider "considerable"?

you should check out previous discussion here about anchors - you would learn a lot, especially from BigInch.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[B.L.Smith]

Thank you littleinch for your reply. I have to give more information about the pipeline.
Line size=20"
Buried length= 40km
Above ground length= 300m
Operating temperature=50°C
Minimum average temperature(install temperature)=5°C
Sunshine temperature= 80°C
And about 2nd question I've to say expansion of unrestrained portion of the pipeline is not negligible and it can move the line break valve roughly about 100mm(i'm not sure about this value yet).

 

[bimr]

Undround pipelines are not anchored. Slack loops can be installed at approximately 700 feet intervals. The slack loop sections are left exposed until the weather and temperature are appropriate to bury the slack loop(s).

 

[LittleInch]

Brad,

Not sure where your 100mm comes from, but I think 300m of pipeline above ground, especially if it is currently straight, is your primary concern. This will need some loops / bends so that it can expand without excessive stress or risk of buckling and falling off the supports. however it doesn't mean the below ground section needs an anchor

otherwise I go along with y firs point - don't put anchors on pipelines - they just don't like it and in most cases it isn't required, just some piping engineers can't handle the fact that one of their inputs moves a few mm.

Most piing stress software can now cope with buried pipelines coming out of the ground without unnecessary anchors. If you need to put in an anchor into the software to make it work, a "notional anchor" a 150 to 200m from the point where it is buried will be OK so long as the model recognises that it is buried.

At 50C from 5 you shouldn't really be in that much difficulty, but 5C? where is this pipeline? looks very low to me.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way