Keen on getting stuck pipe? Try these 5 tricks
To every drilling supervisor, getting stuck pipe is a nightmare. You want to get out, but you can’t. But unlike a bad dream, which is free of charge, stuck pipe costs hundreds of thousands of dollars a day. Still, getting stuck is a character-moulding experience worth its weight in gold.
As a veteran once wrote: “If there is anything that the oil fields ingrain into a man, it’s humility.” It happens to most drilling practitioners, so if it hasn’t happened to you yet, and you’re keen on getting stuck – here are 5 tricks “on the house”.
Trick 1: Drill fast
The first thing you should try in order to get your drill string stuck in the wellbore is to drill fast. Really fast. After all, you’re there to drill, right? So don’t let worries about too high torque or return of cuttings slow you down. Bump up the pace a bit! For many drillers that want to get stuck, this does the trick!
Trick 2: Ignore mud rheology
When drilling in certain formations, fascinating phenomena may occur. Especially if you’re using water-based mud, and you’re drilling through Illite og Smectite minerals. These thirsty fellows tend to swell like instant mashed potato powder when they get in contact with water-based mud. The result? The reactive shales hydrate and start filling your borehole, leaving dodgy clay balls that may obstruct your drill string.
Any Mud Man knows that using the more expensive oil-based mud would stop this swelling process – or more common, treating the mud with KCl, glycol or polymer, which delays the chemical process when water based mud is mixed with formation clay. The latter method also tends to improve the viscosity (resistance to flow) of the mud, which is the mud’s ability to reach a gel-like state, preventing cuttings from being pulled down by gravity and stacking around the drill bit (bit balling) – another well known cause of pipe sticking. Mud rheology is constantly being measured while drilling, but just ignore it and you might get stuck!
Trick 3: Pull out of hole fast!
Pulling the pipe so fast that you cause swabbing is another way of getting stuck. The upward movement of your drill string will then result in a decrease in bottom hole pressure. At a certain point the underground pressure exceeds the hydrostatic pressure of the mud, causing the formation you’re drilling in to practically vomit its formation fluids into the wellbore. When sand, shale, and even pipe protector rubbers are blown up the hole, it may cause what we call blowout-sticking. The key lesson is: Get that drill string out of there fast. Don’t worry too much about wellbore obstructions and ignore overpull while tripping out.
Trick 4: Skip cleaning before POOH
Cleaning the wellbore by circulating the drilling fluids from the bottom up one or two times, before you pull out your drill string, is a best practice. However, if you skip this, the cuttings will clutter the annulus, get pulled down by gravity and stack around your BHA (bottom hole assembly). A good way to get stuck!
Trick 5: Misplace the jar
When you have finally succeeded getting your BHA stuck and someone suggests giving it a kick in the butt, you know what’s coming: The jar! If you want to keep that thing stuck a little longer, by all means, put the jar as far as possible from the BHA and fire it off. Not much will happen – and you will still be stuck.
P.S. Did you ever run into stuckpipe problems? How did it happen? What’s your story? We’d love to hear about your own experiences. Maybe we could extend the list with your help?
By: Hans Petter Moen
Hans Petter Moen has more than 30 years’ experience from the offshore / onshore oil & gas industry as Drilling Section Leader and Drilling Supervisor. He is currently Adviser Marketing, Technology & Operations at Odfjell Well Services.