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# I am trying to calculate how long it will my pipe to reach a certain pressure

## I am trying to calculate how long it will my pipe to reach a certain pressure

(OP)
I have about 1640 ft pipe Carbon steel with condensate around 13000 Barrel at day. The line is operating at 150 PSIG. How long (time) it will take to build up a certain amount of pressure for a blocked flow scenario.

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Depends on what is causing the pressure?

Could be < 1 second or hours if there is a very slow thermal locked in increase.

Much more definition of the issue required.

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

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

(OP)
a block flow scenario for example

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Assuming you start counting from the point where your flow at the far end goes to zero and you are still pumping in at the same rate, my best guess is about 10 to 15 seconds to reach the dead head / no flow pressure for a pipe of about 300m.

You can work it out if you want using a transient simulation program, but how accurate do you want to be and why do you want to know?

The fluid will compress a little bit (Bulk Modulus) and the pipe will expand a little bit which is why the answer is >0, but it's much less than 1 minute.

You're probably looking at about 0.5% of the pipe volume to go from low pressure to dead head pressure.

But this is all very vague as you have not defined how much pressure is to be in excess of the steady state - 10 psi? 100?, 1000?, size or wall thickness of the pipe, Bulk modulus of the fluid, pump curve etc.

All of the above is based on this being 100% liquid. Throw any gas in there and the answer is different.

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

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

You will begin seeing a pressure increase at the beginning of the pipeline in 0.5 to 1 second and probably reach maximum pressure within 4 to 5 seconds. Maximum pressure reached will depend on the liquid's initial velocity in the pipe and how fast the blockage is fully closed. Max Pressures couldreach around 1.5 times initial pressure (225 psig) more or less, probably less with condensates, but I don't know the Velocity (pipe diameter), which is important.

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Context is important here.

Surge could be an issue if you are at a high velocity and close the valve quickly.

Different if you start with a closed valve then turn the pump on.

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

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

What pump?

** That's the longest que I've ever seen and I can't see the end of it. **

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Exactly. We know nothing but something is making it flow..

And yes, I've seen it and it's A HUGE queue

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

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Might be just gravity.

The pipe that is, not the long ques. How long does it take to get inside?

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

It looks like it's 0.5 miles per hour.

Current queue is over 5....

I'm not in it.

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

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Mr. Smith is as usual, frugal with his words.

What causes pressure rise during blocked flow?
a) Solar radiation heating up the blocked in condensate, resulting in thermal expansion
or
b)Some pump upstream goes into dead head when an automated valve downstream slams closed

or something else

Either way, make an effort to describe this event, and respond to comments. Both @LI and @1503 are going round in circles trying to guess.

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

Hi,
We have no information about the initial conditions, the size of the pipe, what is the driven force, the credible scenario leading to this query.
The OP should simulate the condition with a flex hose in his garden.
Pierre

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

CNN said 4 miles and 11 hrs. That's LONG.

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

There's a dedicated you tube site run by the government. Just search "Queue tracker " on YT.

It's reached the park at the start point and loads of zig zags in there so now 5 miles and 14 hours....

PS In the abscess of data, apologies for hijacking the thread.

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

### RE: I am trying to calculate how long it will my pipe to reach a certain pressure

We're not hijacking, just passing time waiting for OP's ANSWERS.

Not joining that que!

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

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