In episode 86 of Ask Brock, host and drilling trainer Brock Yordy takes a question from Brian in South Dakota about the difficulty of reverse mud versus direct mud rotary drilling.

“I think it all comes down to our fluid combination,” Yordy says, “and inhibiting, making sure those reactive soils don’t react, don’t get sticky, don’t swell, don’t start to boot off on us.”

He discusses bit jetting, surface area, polymers and rotation, which all feed into the difference between the two methods.

“Shales and clays have an affinity for steel,” he says, “because of their charge and the charge of the steel.”

Both methods, he says, benefit from a good, competent fluids mix versus fresh water — which plenty of drillers still insist on using. Check out today’s episode to hear more.

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