Drilling with basic WBM & doing it cheap & clean.

It seems that these days, some certain ways of drilling with mud have been forgotten or never passed on to the new generation of mud engineers. I wanted to put this out there to help some of the mud engineers who simply never thought of doing things this way.  There are 100 ways to drill a well & all might work, but it doesn't mean the way you are doing it is the most efficient way. If you have not be doing like I say below, you might think it's going to take a lot more work doing it my way.  But after doing it, you will find that everything actually runs smoother & takes less work overall.

I just wanted to explain mud philosophy that has worked really well for me & operators over the years.  I know this might sound common sense, but I know common sense is not so common so just in case, I figured I would tell you my thoughts.

I believe in doing the customer good jobs.  

I believe in giving them the most bangs for their buck.

I know the one mud property that has a direct correlation with high ROP is a low PV.

When you utilize your primary shakers properly, you can be at less than 5% LGS with never even running centrifuges. I try to run my mud with as low PV as possible by mainly utilizing my primary solids control (ie the shakers). Although centrifuges are useful, they have a place & a time. I do not like to run centrifuges unless I absolutely have to because it throws away not just drilled solids, but the additives as well.  When utilizing my primaries properly, I have managed to drill wells all over with less than 5% LGS (& usually less than 3%).

The finer I can get on shakers, the lower the solids, the lower the PV, the higher the ROP.

Also, less LGS = less pump down time

Less LGS also means less need to dilute & less product use.

200 mesh screens is the minimum to take out all sand size particles. Barite sometimes has particles sized greater than 200 mesh but you do not really want those particles in mud as they will cause you to need to change liners more frequently (down time).

Once you get a few circulations with all 200's & mud is "cleaned up", much of the Barite gets ground even further & it allows you to possibly even screen up further (to like 230's) without removal of hardly any Barite (if already at desired weight).

For Lignite or other black powders, I try to presolubilize & bleed I into active. This gives greatest bang for buck as you do not lose the powers over the shakers. Another thing is since it takes a while to solubilize; some of that caustic will make it all the way around a circulation before interacting with the black powders. What that causes is a higher pf of the fluid going in the hole & that means the fluid entering the formation (ie the pf being high) more reactive (which is bad).  Want to know exactly how much Caustic it takes to presolubailze black powders? 1 sx of Caustic per row of black powder on a pallet. In other words 7 sxs Carbonox per row = 1 sx Caustic. 5 sxs Quick Thin per row = 1 sack of Caustic.  Most people don’t even realize why they were stacked that way ;-).   I usually presolubilize at least a full pallet of Carbonox in 40-50 bbls.  Get the Caustic in 1st then have them slam the Carbonox as fast as they can.  If it starts to foam up too much, turn mixing pump off, add Aluminum Stearate (& diesel). Once foam decreases finish additions,.  You can add other stuff in the presolubilized pit too EXCEPT Lime.  Lime will treat out the Carbonox & you will end up with 50 bbls of black water with a 60 water loss! I sometime add Pac, Gel & or Quick Thin (with appropriate Caustic). Same is true with Soltex & Baratrol Plus. I then get it bled over 1-2 full circulations. If they want sweeps, what you do is build it as fast as you can, then send it to the trip tank & you can bleed it over from there, freeing up the slug pit for sweeps again.

If you are doing pad wells, the cost on 1st intermediate is the highest, but usually under programed cost & I try to make it great for the future intermediates where they get a Cadillac fluid at a Ford Fiesta price. Using that philosophy I've managed to drill several wells at record speeds & yet the cheapest of all costs.

If / when on a OBM / SBM section, I know we usually get used mud.  One trick I learned for helping to clean mud up is when we reach casing point, to screen up while running casing.  When running casing, they pump at lower rates than while drilling & it allows a chance to get finer screens than could be achieved while drilling.  I utilized this process up in areas where LGS was all in the 15-25% range.  Every single well that utilized my system dropped the LGS into 7-10% ranges (not just wells I was on, I went around & explained technique to other mud engineers in area).

Try to run as low as possible, but not by dilution, but by utilizing my primary shakers most efficiently!

Don't think it will just run up the operator’s shaker screen bill. Constantly repair bad screen with careful clear silicone repairs & when running clean mud, you might be surprised but with the less solids, the screens life gets extended.  It just takes a while & a lot of TLC to get there though. On repairing screens, first wash both front & back & all sides clean. Allow to dry. When using clear silicone, I usually squirt from back to front, and then I smooth out on front & apply more if needed. It takes 24 hours to cure. I have drilled several thousand feet of 12.25" hole with a lightly weighted (10.7 ppg) mud with 200's on everything & managed over 36 hours before even the 1st screen began to show wear.

CHANGE SCREENS THAT HAVE WEAR, NOT JUST IF HOLES. Then repair those worn screens!

If I am successful in presolubilizing all my black powders, I tend to run my mud with a low pF & most of my pH is from Lime.  I like this because low pF means the filtrate entering the formation will be less reactive. I add Lime in active, NEVER in presolubilized pit. The Lime ensures minimal Carbonates & minimizes effects of gas & helps guard against H2S.  Once fully broken over good amount of Lime will give a better retort analysis because those tiny bubbles carbonates cause show as solids on a retort. This also will help give flat gels (again after fully breaking over). Trick is high pM (alkalinity of mud) with low pF (alkalinity of filtrate).

 Dress shakers with minimal of 170 mesh screens each. work your way up from there. Each chance you can get even 1 shaker screened up, do it. It shouldn't take too long to have 200's everywhere & maybe even 230's.

Rig up dump lines from Sand Trap, desilter, desander & setting pits. Dump sand traps per connection (till fluid start moving through dump). Every 3-4 dumps, switch to desilter, desander & setting pits 1 at a time & once through all, begin rotation again.

Something else about low LGS in pay zones; less LGS the higher the production of the well in its life cycle.  What we do with LGS may not matter too much to a drilling engineer, but I guarantee the reservoir engineer will thank us.  Sometimes you do a good job for the operator despite a drilling superintendent’s ignorance.  It’s not just about drilling wells fast & cheap, it’s about getting the most production from a well. It’s up to us to look past the ignorance that sometimes comes on the drilling side & do what’s best for the well & help justify what we do with reasons I gave above (higher ROP, less pump down time, less dilution, etc).

When reservoir engineer used to be more involved in the drilling & mud programs, there was a pretty standard less than 5% LGS, as they became less involved in drifted to less tha n 5% drill solids. As we have seem to grown further away from those days, it's now grown to less than 10% LGS with some & even not a concern for others. Sensibility for sake of the well life cycle, not to mention you can actually do wells cheaper & faster needs to return

PV = Plastic Viscosity (size & or amount of solids)

pF = how causticized the filtrate is (what is entering the formation)

pM = how causticized the mud is (just mud & not what gets “squeezed” out of mud into the formation)

LGS = solids that are not Barite

If you agree & or found this helpful, please feel free to share.