Avoid costly breakdowns and downtime with these helpful tips from directional drill manufacturers.
Equipment maintenance is never a trivial matter, but when it comes to directional drilling, it perhaps carries a bit of extra weight.
That’s because an equipment breakdown in the field due to neglected maintenance doesn’t just mean downtime. It could mean completely abandoning a hole mid-bore and starting a job over at the beginning. It’s not easy removing broken-down equipment from belowground and still be able to make use of that hole, say HDD product manufacturers.
One of the primary components that can create problems when not maintained is drill pipe.
“Drill pipe is probably the most wearable item on a directional drill,” says Barry Jackson, HDD product training manager for Toro. “Drill pipe is not super expensive, but just keeping your pipe serviceable is important because it can make or break a directional bore.”
Drill pipe maintenance begins with proper operation.
“There are limits to how much a piece of drill pipe can be bent — or steered — in any one direction before it loses the ability to spring back,” Jackson says.
Most manufacturers recommend a deviation of 10 percent, he says. For example, a 10-foot piece of pipe could be steered 1 foot in a given direction over that length.
“But I’ve seen people go as much as 20 percent on some of these bores,” Jackson says. “They’ll go beyond that recommended 10 percent and try to rotate it when the pipe is bent 20 percent and all of a sudden a piece of pipe breaks downhole.”
Even if drill pipe doesn’t break downhole, steering beyond its ability could compromise it for future jobs.
“You want to make sure you practice consistent steering. You don’t want to have to overcorrect. You want gradual turn,” says Jaime Wines, HDD tooling product manager for Ditch Witch. “Anything that you’re oversteering can cause damage to the pipe or the tooling, causing it to maybe break downhole on the next job.”
Even with proper operation, drill pipe is a component in which wear is inevitable. In order to maximize the life of drill pipe, Jackson recommends rotating it throughout the drill string.
“Instead of starting with the same piece of drill pipe every single time, you should rotate it throughout the string so that every piece of pipe gets even wear,” he says. “Along with that, it’s also important to use the right drilling fluids. The drilling fluids that are used will greatly reduce the amount of wear on the drill pipe, as well as the tooling on the bottom of the drill string.”
It’s also critical to keep the threads that connect the various pieces of drill pipe in good shape. Any time there’s damage on a thread, it’s also damaging anything it’s connecting to down the drill string, Wines says.
“Use grease every time, every single tool joint,” she says.
She also recommends protecting drill pipe threads when not in use by using a thread cap, or even just tape. “Anything they can put on them to protect them from gouging.”
Eventually, drill pipe needs to be replaced. Wines says keep an eye on any wear-indicating features. For example, Ditch Witch machines use pipe with grooves on the outside diameter of the joint that show how much wear has occurred.
“It’s very difficult for people to know when they should change pipe out, so that’s why the wear indicator is there — to help contractors see that,” Wines says.
Jackson says a common range in which drill pipe manufacturers recommend replacement is 20 percent wear.
Before it gets to that point though, proper equipment operation and maintenance practices can help drill pipe stay serviceable for as long as possible.
Says Jackson: “I’ve seen drills with original drill pipe on them that was five years old. I’ve also seen some drills that were less than a year old and had to have the drill pipe completely replaced.”