Drilling advances

	Vol. 226 No. 4
LES SKINNER, PE CONTRIBUTING EDITOR

Rig automation. Recent advancements in the processes required to drill oil/gas wells have been the subject of many discussions, conferences and papers of late. Rig automation: Is it as good as we believe? Automation probably started with the guy that figured out how to lengthen the rope as the well got deeper so he wouldn’t have to climb out on the spring pole and re-tie the knot. It continued with mechanical enablers during the time when a reliable weight indicator and standpipe pressure gauge were about the only things needed to drill a well. All other information on the drilling process came to the driller in the form of subtle cues: the squeak of the brake, the speed of the pump engine, the whirr of a gearbox, the slap of a chain inside its guard. Pilots still flew by the seat of their pants – drillers drilled the same way.

Pneumatic devices came along next, with a cable to raise the brake handle. This meant the automatic driller controlled the weight on the bit so a man didn’t have to stand on the floor for long hours manually “drilling” the well. Unfortunately, some of these devices were unreliable, and the driller had to stay available close by to quickly override the system.

Monitoring was performed by analog devices. Certain functions, such as weight on bit, pump pressure and penetration rate, were recorded by ink pens marking a paper chart until some condition made a hard copy record of that information unappealing for the crew. Then, the geolograph would mysteriously quit working. Without the recorded chart from the tattletale, there was no evidence of poor performance.

Now, with high-speed reliable data-monitoring systems and remote displays of every conceivable piece of information on the rig, it’s harder (but not impossible) to sabotage the tattletale. Variations from setpoints are accompanied by alarms, flashing displays, differing colors, sounds, vibration and a host of other signals.

Fortunately, technology has also provided the rig with automated capabilities, many of which can be performed remotely. For example, pump speed on electric rigs can be adjusted to a particular setpoint. Then a controller adjusts input horsepower (electric current, whether DC or AC) to sustain that speed, regardless of what happens on the pressure end of the pump. Rotary speeds are similarly controlled by a computer. Weight on bit is controlled by a servo-motor operating the drawworks. The new electric rig doesn’t even have a mechanical brake.

Other devices are prevalent to perform many of the functions formerly performed by a group of tough men. Iron roughnecks now make connections. The spinning tongs have taken the place of the spinning chain operated off the drawworks. The pipe is now racked by a hydraulic derrickman. The fingers are still at the board, but the pipe racking system is operated by a man standing on the rig floor.

All of these devices have successfully reduced exposure and risk to crews. There is little risk of dropped objects when there is nobody on the floor inside the derrick legs. There are fewer mashed hands and broken arms from throwing the spinning chain. One of the finest omissions, so far, is the demise of the cathead. This means, of course, that the forklift has moved into undisputed first place as the most dangerous piece of equipment on the rig (according to my old friend Max Hall).

These tools have also allowed for a reduction in some crews. Super singles are now being fabricated in West Texas and other places that operate with a crew of two – a driller and a floorman. The floorman operates the iron roughneck, kelly spinner, spinning tongs and the pipe racking arm. The driller operates all other aspects of the rig, including hoisting equipment, pumps, generators, mud system, well control devices and the rotary system. Nobody is in the derrick; nobody is on the floor. Just machines.

Drillers are now seated in ergonomically designed chairs behind panels in cabins where the loudest noise is the rush of air from a vent.

At the touch of a button or two, they can change the display to show the output from one of several different sensor collections. Computers run more and more of the functions that drillers formerly performed, with much greater accuracy and speed.

Still, we should be reminded that a computer is nothing more than a high-speed idiot (despite advances in artificial intelligence). A computer can only do what it’s told to do by a program. While they can handle certain tasks well, computers lack the ability to synthesize unexpected data and adapt reliably to changes.

In a presentation to an SPE study group recently, Keith Womers said that software programmers are neither drillers, psychologists nor ergonomic experts. Early drilling automation programs were woefully deficient in handling certain tasks, because the programmers didn’t understand what was needed. Crews resented having a “Big Brother” looking over their shoulders constantly (they still do), and remote “control” of the drilling operation by someone in an office 300 miles away was/is highly resented.

Computers crash. Sensors fail. There is still a need for a human to intervene at the drillsite. Primary local control of drilling operations at the drillsite is a reality now and will continue to be until a large number of the current generation of drillers, engineers and supervisors dies off.

So what can we expect in the future? Easy answer – more automation. Just as aircraft require more and more computer control and automation to fly increasingly complicated planes, drilling rigs in the future will need a greater number of reliable automation systems, better programs and faster computers. Greater demands on the drilling industry with ever increasing TDs, temperatures and pressures in more challenging locations – such as the seafloor drilling rig – will require a greater reliance on computer-operated monitoring and control systems.

Who will operate these rigs? On a recent trip to South Texas while visiting one of the new third-generation electric rigs, I asked a young driller where he got the experience necessary to run the rig from the console. He confirmed my suspicions by saying, “From playing video games.” In a surprise move to my family, I have reversed my philosophy. I now encourage my grandson to play video games on his computer. 

Les Skinner, VP and Division Manager for Energy Personnel International, Houston, and a chemical engineering graduate from Texas Tech University, has 32 years’ experience in drilling and well control with major/ independent operators and well-control companies.