WorldWide Drilling Resource

17 WorldWide Drilling Resource ® NOVEMBER 2014 Drilling Fluid Updates by Ray McLarty Drilling Fluids & Grouts Questions & Answers Question Why do you recommend the use of Quik Gel when drilling in clay? Seems like a waste, mixing clay to drill in clay. Answer Normally, what I would recommend for drilling in an all-clay formation would be EZ-MUD ® GOLD , an easily dispersible low-viscosity PHPA (partially-hydrolyzed polyacrylamide) dry polymer. When mixed at a rate of ½ pound per 100 gallons of mix water, this type of product does an excellent job of helping to control hydra- tion and the swelling of clay formations. If the clay encountered is a sticky, swelling clay, then I would also add PENETROL ® , a highly concentrated surfactant. PENETROL ® , or similar products, when mixed at a rate of 1 quart per 100 gallons of mix water, do a really good job of controlling sticky clays and keeping the drill bit and rods clean. However, when drilling a well, you are usually going to encounter a permeable formation such as sand gravel, or a combination sand gravel clay, etc. at some point. Because of this, I recommend you start off mixing a QUIK-GEL ® type product as your base product, to which you can add polymers, surfactants, or other additives as needed. Four reasons, off the top of my head, for mixing bentonite drilling mud when drilling in clay would be: 1. No product, either man-made or naturally occurring, has all the char- acteristics (viscosity, density, gel strength, filter cake) that enable it to perform the many functions re- quired of a drilling fluid, except a high- yield sodium bentonite drilling mud, such as QUIK-GEL ® . These charac- teristics are required to control, sta- bilize, and keep the hole clean as the operator drills through the var- ious formations encountered. 2. When drilling in clay formations, some contractors feel they can use the native clay in the formation to create a drilling mud. They can, but a native clay drilling mud is not measurable and is inconsistent. It is not a problem solver, it is a prob- lem creator. 3. QUIK-GEL ® , like all high-yield drill- ing muds, contains polymers. Mixing bentonite drilling mud when drilling in a clay formation can help control swelling of the clay formations by coating the clay, thereby preventing hydration and swelling. 4. Mixing high-yield bentonite drilling mud when drilling in clay is not going to do any harm, and it just might save your behind down the road. Note: QUIK-GEL ® , EZ-MUD ® GOLD , and PENETROL ® are Baroid IDP prod- ucts. Similar products to QUIK-GEL ® would be CETCO ® SUPER GEL-X ® or Wyo-Ben EXTRA HIGH YIELD™ . Pro- ducts similar to EZ-MUD ® GOLD would be CETCO ® CLAY CUTTER™ or Wyo- Ben DRIL-SOL™ . A similar product to Baroid PENETROL ® would be CETCO ® DRILL-TERGE™ . The statements and comments in this article are my own and are based on information and references believed to be true and factual. If you have a question or comment on this article, or on bentonite drilling muds, polymers, grouts, or additives, please forward them to me in care of WWDR . Ray Ray McLarty may be contacted via e-mail at michele@wwdr-usa.com