Cutting premium threads: automated oil coupling cell solves a barrel full of production problems.

Position:Hot markets review: oil, gas


Oil couplings were being manufactured on manual lathes or NC machines in 1977 when ES. Reddy, Okuma product specialist, began in the business. About a year later, CNC machines came on the scene for production, and premium threads or proprietary threading oil drill-pipe couplings also were developed then.

While the concept of oil coupling production hasn't changed much, the need to produce better, faster, safer, and more accurate couplings has. Okuma and Partners in THINC have collaborated to create automated oil coupling cell solutions unique to the industry--to help meet growing demands on the oil and energy business.

"The standard methods for coupling production have included a lot of manual loading and unloading of coupling material into older equipment with the operator constantly stop ping the machine to remove chips, particularly during the threading process," Reddy says.

"Cutting over chips, breaking an insert, high scrap rates and operator injuries were issues customers told us they would like to resolve," he says. "No one had previously pursued this because of the time and money involved."

Enter Okuma and a group of collaborators.

Out went at least three machines and three operators from the conventional method for production. They weren't needed with the new automated cell.

The new automated oil coupling cell features the four-axis Okuma Lathe Oil Country (LOC650), a two-axis Okuma V80R vertical turning lathe, and a Fanuc gantry robot.

For the 14.75 throughbore cell, the robot loads a double-length coupling blank weighing approximately 105 pounds into the LOC650 (zone l). The lathe performs the ID and OD roughing and finishing and a cut-off operation to produce two 10" couplings before sending the processed couplings down a gravity-fed conveyor to the VSOR lathe (zone 2) for threading, profiling, and finishing.

Coupling cycles

A complete 9 5/8" diameter premium coupling can be produced in approximately 11-12 minutes, 24 hours a day. If parts, tools or maintenance become necessary in one zone, the other zone can still continue production, avoiding an entire operation standstill.

"Besides the fact that the robot does all of the heavy lifting and there are no additional set-ups involved, we've tackled the chip evacuation issues that have also kept operators busy throughout the cutting process," Reddy says. "A lot of this wouldn't be possible without the participation from so many of our collaborators at...

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