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WW, AK, Captainswag (?- really?!), dspp et-al; just a noily suggestion: Could the vds-esp commissioning be realted also to the high PI/natural drawdown rates getting close to, or inducing, cavitation/buble formation at flow discontinuities ('rough bits'); i.e apply a bit of +ve pressure downstream of pump = subsea lines preserved better?
Just a thought, haven't done any math on it.
gla
'bubble', ffs, not buble.
Heaven forbid.
Sorry - gla
Wellwell,
Think through what one would need to do with each well for a month, on a day-by-day basis. Make an assumption about flow rate and watercut for each well. Do it in such a way as to match the OGA data for the five months. Build yourself a little excel spreadsheet. Plot the resultant scatter plot. It is possible, but not as obvious as one might think. Your latest is a small subset of those perms & coms, and one of the more unlikely ones as it does not obviously correspond with other statements that HUR have made that also need to be respected. I am afraid that trying to figure out what is going on subsurface from surface data is challenging at the best of times, but even more challenging when there is unknown (or unreleased) data. Hence my very cautious four hypotheses.
regards,
dspp
SG,
I think you are overthinking this. Having said that subsea tie-backs are not my speciality. However I think you will find that the well flow is primarily choked at the subsea tree. The flowline length is therefore not ordinarily (if ever) exposed to full CITHP or full FTHP. One then manages the topsides control valves (I cannot for the life of me remember if these are referred to as chokes, it is a very long time since I have worked on FPSO stuff, there may be a PCV or FCV in there, or not) so as to get the first stage sep entrance pressure one desires. So the well drawdown is primarily controlled at the tree choke, ideally critical flow. Only if reservoir pressure has dramatically decayed would one need to switch on a ESP so as to bring flowline pressure up (and increase drawdown). So far HUR have not released any production pressure data of consequence AFAIK. The ESP rumor may be incorrect, innocuous, or not.
regards, dspp
Thanks for the reply. I'm clearly grabbing a positive (bias) view but I'm hoping that is the correct one.
GE exit polls might help tomorrow.
SG2,
(Context, rerad your message on phone while having 'digestif' in latenight cafe, finished glass in a oner, scooted off home to reply before more samage gets done..)
"WW, AK, Captainswag (?- really?!), dspp et-al; just a noily suggestion: Could the vds-esp commissioning be realted also to the high PI/natural drawdown rates getting close to, or inducing, cavitation/buble formation at flow discontinuities ('rough bits'); i.e apply a bit of +ve pressure downstream of pump = subsea lines preserved better? "
It's rare that I'll 'jump on' noilbys' suppositions outright, but in this case (for the sake of speed and brevity) I have to. No, you're wrong. In fact completely 180 degrees offtrack.
" Just a thought, haven't done any math on it."
Don't waste your time trying to for now. (No offense intended.) If (especially in a fractured reservoir and a horizontal hole) you have any vague worries about gas / oil ratio increasing (ie approach to 'bubble point') or increased watercut, absolutely the LAST thing to do is to increase 'suck' on the well. Instead quite the opposite. You either choke it down (limiting production rate) or shut the dam thing in until things reach a new equilibrium.
Sorry, but that's just how it is. And why I've got a bit cross-threaded with Dspp for raising questions about the ESP commissioning, and raising doubts.
Must rush, to sign in to online poker game, with election results on the TV in the background.
PS xcuse typos, pls. written hurriedly.
dspp,
" I am afraid that trying to figure out what is going on subsurface from surface data is challenging at the best of times"
Yeah, but can you suggest a better way? Yes, I'm sure you can ( ;-) ), but Lancaster is open-hole 'barefoot'. So no question of 'smart completions' there, relaying realtime downhole data from below the production packer, with a possibility of switching zones or whatever.
I'm afraid I still 'challenge' your own contention that anything can be read into the OGA data (showing just five datapoints) than just the simple figures shown, for information, not interpretation.
And anyway, you still haven't come back to argue with me about the fact that the July watercut percentage was lower than June, but with an increased flowrate, and the fact that that particular datapiont is further 'beneath the line' than the September one (which you concentrate on) is above it.