ShopSolutions Case Histories of Manufacturing Problem Solving Texas-Sized Tools for Oil Patch Jobs P
arts used in the oil drilling business for the Oil Patch are tough and large with hardness of Rc 36–40 with diameters to 40" (1016 mm), lengths to 220" (5.6 m), and weighing up to 2 t. They require equally tough, rigid, highly flexible machine tools to deal with them. Some shops with the right tools thrive on the challenge of machining these workpieces.
Juan Alvarez has spent the better part of 40 years in the “Oil Patch” in Texas, as a leading manufacturer of drilling and downhole tools with several major oil-field equipment manufacturers. Today, Alvarez is president of JNB Machine Shop, a ten-year-old supplier of com- ponents for downhole drilling applica- tions in oil wells. JNB is a 12,800 ft² (1189 m²) two-bay shop with a 5-t crane in each bay.
“The downhole components that we machine are integrated in a larger assembly that makes up the drilling jar,” Alvarez says. “The drilling jar is the part that does the actual drilling. It has bits that cut into the ground. We make shafts, the mandrels, that are part of the drilling jar. And some of these are very long, very large, and very heavy. When these parts are assembled into the drilling jar, the splines engage with another mandrel that has splines, and they are aligned in such a fashion that they provide the torque required for the drilling forces. This is when the jar is
that we run can feature up to a 40" [1016-mm] OD short lengths and can weigh up to 2 t. Previously, we were running the mandrels in a process that required multiple machines. These long parts required turning the mandrel around to machine both ends. The hardness of the material for downhole tools typically is Rc 36–40.
We’d do the turning
on a lathe, and then move the part to a mill, do a complete setup, and then mill the splines. So, moving these mandrels from machine to machine not only encouraged damage but involved time-consuming, difficult, and delicate maneuvering involving forklifts and cranes.”
JC Payne (left), vice president, and Juan Alvarez, president of JNB Machine, with the L700MA heavy-duty CNC turning center, one of four Hyundai WIA advanced machines used for machining tough Oil Patch workpieces.
rotating and doing the drilling. So these splines interlock with other splines and that provides the torque for the rotational movement of the drilling jar as it rotates and cuts.” “The types of materials we turn and mill include 4140, 4340, 4330 steel—all for downhole applications,” explains John “JC” Payne, JNB vice president. “The majority of parts machined are mandrels. Some mandrels can be as long as 220" [5.6 m] in length with an 8" [203-mm] OD. Other parts
Everything has changed now that JNB invested in several new Hyundai WIA machines–a VX650-50 VMC, two L700MA turning centers with live tooling, and an L600 turning cen- ter. They have rendered the previous multi-machine process obsolete. “Now these parts are run in a single setup on a single lathe,” says Payne. “We load the part on the machine, machine each feature, take it off and it’s ready for shipment. We have gained 30–50% efficiency with the new Hyundais and can now