Pressure drop issue
Pressure drop issue
(OP)
I´m having an issue on a job we ran involving hydraulics and leak pipe.
We ran a pipe downhole 10,000 ft, once reached bottom we tried to pressure up the pipe to 3,500 psi so our tool (located at the bottom end of the pipe) could be activated and setup. We noticed the pressure dropped instantly once we stopped pumping.
We noticed there was a leak 4,500 ft (+/- half distance), and tried to pressure up to 5,500 psi with no sucess. We pumped fluid (1 BPM) for an hour holding the pressure to 5,500 psi and still didnt notice our tool being activated, somehow the pressure didnt reach bottom.
Can anyone tell me what happened? Is there any theory or mathematical explanation I could relay on?
We ran a pipe downhole 10,000 ft, once reached bottom we tried to pressure up the pipe to 3,500 psi so our tool (located at the bottom end of the pipe) could be activated and setup. We noticed the pressure dropped instantly once we stopped pumping.
We noticed there was a leak 4,500 ft (+/- half distance), and tried to pressure up to 5,500 psi with no sucess. We pumped fluid (1 BPM) for an hour holding the pressure to 5,500 psi and still didnt notice our tool being activated, somehow the pressure didnt reach bottom.
Can anyone tell me what happened? Is there any theory or mathematical explanation I could relay on?





RE: Pressure drop issue
RE: Pressure drop issue
Unfortunately, your options are rather limited. You could try continuing to pump your fluid in the hopes that you will eventually be able to pressurize the system. However, there is no guarantee on this and you could end up creating a much bigger problem.
Not being familiar with your industry, I'm not sure if it is even possible to repair the pipe. If not, hopefully you can at least retrieve your equipment.
In any case, I'd suggest a rigorous review of what happened that caused the leak so as to prevent this problem from recurring.
Patricia Lougheed
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RE: Pressure drop issue
I would start by doing a pressure drop calculation based on flowrate for the length of hose to the leak. This will calculate the pressure immediately next to the leak, and hence the pressure to the tool. If this comes out higher than the pressure to activate your tool then this is why.
RE: Pressure drop issue
It might help if you tell us what pressure your tool needs to be activated ? Is it reasonable to assume 3500psi should be enough ?
RE: Pressure drop issue
Again as a few people ahve said though its the gaping hole int he pipe thats causing your problem, id pull that string out and find out what ahppened.
Either that or your tool fell off the end of the string, one of those options is my best guess.