Tough RFID Tag Strikes Oil

"The drilling operation is very expensive," says Kemal Farid, Merrick president and CEO, and a string of drill pipes can cost $1 million or more. Oil wells are like cork screws, he says, with turns and twists that can damage or weaken a pipe. Temperatures within the holes can vary from 400 degrees Fahrenheit to -320 degrees when liquid nitrogen is used as an inert substance added to create a buffer inside the well. The pressure can be more than 20,000 pounds per square inch (psi). If one piece of a drill breaks, the entire string must be removed, costing many hours of delay.

With the Merrick system, drillers use a computer to design the drill string they will need. The string consists of various sizes of pipes and joints that connect those pipes, all of which are tagged. Oil drillers also use pipe for special purposes such as recording the hole angle or geological information. Merrick software enables drillers to locate the specific ID numbers on the pieces they will be using. They then use a handheld reader to identify the necessary pipes and joints by capturing their tag ID numbers. Each pipe has three RFID tags encoded with the same ID number specific to that piece of equipment. The data related to those pipes, such as where and how they have been used, is stored on a local server and can then be backed up to a server that can be hosted by Merrick or the drilling company or leaser.

The tags are designed to withstand exposure to heat and other physical forces generated by the drilling process and be readable through heavy coatings of mud.

After its tag is read, a pipe section or joint is connected with other pieces in a string that is then drilled into the ground. As the drill equipment operates, the drilling rig's sensor system tracks the torque, axial tension, and downhole pressure and temperature. That data is then stored in the server using Merrick software to link it with the specific pieces of equipment involved. Companies such as Trailblazer can then access that data before reusing a pipe to know what kinds of conditions it has been exposed to in the past.

By the end of the year, Farid says, Merrick will be installing fixed readers below the drilling floor—the platform of the drilling rig where drilling operations are conducted—allowing the RFID tags to be read as the pipe sections are lowered. Farid also says there has been interest from the drilling industry in adding RFID tags to torque wrenches in order to track the amount of torque on bolts used to hold drilling equipment in place. Accidents can occur on oil rigs and at drilling operations when one or a series of bolts breaks because of errors in torque.

Currently the Merrick RFID system, says Binmore, "is hands-down the most rugged RFID tag available for drilling operations." The tag has been tested up to 22,000 psi and can operate under exposure to 360 degrees Fahrenheit indefinitely, rather than more typical tags that can survive such heat for only short periods of time. Binmore explains Merrick accomplished that heat and pressure resistance through the design of the casing and configuration of the tag, but says that exactly how the company achieved this is proprietary information.