6 replies to this topic

[mehdi0211]

Dear all,

I am studying a 750 km pipeline in order to detect if there is any surge pressure caused by a sudden valve closure. I have been given assignment to design a surge tank.
I highly appreciate if someone can help me how to start. 
Thanks a lot 
Regards 

 

[fallah]

 

Hi Mehdi,

 

 

At first let's know the detail of the pipeline and the reason(s) based on which you recognized the necessity of considering a surge tank for protection of mentioned pipeline.

[Bobby Strain]

There is no pipeline in the world that is continuous for 750 km. Whether liquid, dense phase, or vapor, there will be breaks with compressors or pumps. Maybe you meant 75 km?

 

Bobby

[mehdi0211]

Hi FALLAH,

It's a 750 km pipeline with a six pump stations, pipeline material carbon steel with grade used X60, X65
dn = 12 in, wall thickness = 0.25 in and transporting hydrocarbon fluids.

Example for the surge event that i noticed:

I have a pump station at x = 490.5 km with P = 85 bar (discharge pressure), the valve located at x=494.25 km closes in t=12 sec 

The pressure registered in the upstream of the valve (Pmax= 142 bar) exceeds the Maximum Allowable Surge Pressure of the pipeline (MASP)

Therefore to prevent this problem I have to plant a surge tank 

[mehdi0211]

Bobby:

 

It's a 750 km pipeline with a six pump stations

 

Mehdi

[Bobby Strain]

You should enlist the services of a professional who can lead you to the proper solution. It might be as simple as changing the valve(s) stroke time.

 

Bobby

[mehdi0211]

You should enlist the services of a professional who can lead you to the proper solution. It might be as simple as changing the valve(s) stroke time.

 

Bobby

Hi

I had tried to change the valve stroke time before. but this solution is not relevant in some cases, for example :

- In an emergency shutoff 

- Or when the stroke time should be upper then one and half minute to avoid the surge event. 

therefore the remain solution is to plant a surge tank in the upstream of the valve

 

Mehdi