First Downhole Drilling Chip Developed

By Heather Bence

Perseverance not only pays off but is essential in much of the innovative research and development that pushes the envelope at Saudi Aramco's EXPEC Advanced Research Center (EXPEC ARC).

The EXPEC ARC Drilling Technology Team (DTT) recently achieved the first major field test milestone of its four-year project to develop industry's first downhole drilling microchip.

"This important stage of the microchip technology development has proven that the project is on the right track to deploy such a miniature device for practical and useful applications in the near future," said Nasser Al-Khanferi, DTT chief technologist. "This is a strong achievement for our Drilling Technology Team, and the future holds even greater opportunities for more technologies to come."

The concept may have seemed far-fetched years ago when, during an SPE conference, a casual meeting between Shaohua Zhou, DTT technologist, and a Tulsa University professor turned into a serious business venture.

"Our dream was to develop a low-cost and alternative downhole data acquisition system capable of recording measurements such as pressure and temperature along the circulating path of drilling fluids," said Zhou. "Such a technology would optimize mud and cement formulations while drilling and further reduce well cost by providing an alternative low cost data acquisition system."

It was quickly realized that the idea could potentially change the way the industry acquires downhole data. Such data is rarely available in shallow and intermediate hole sections and can help drillers more readily diagnose hole problems while drilling to optimize and improve rig operations.

After extensive technical discussions between EXPEC ARC and Tulsa University teams, a research program was well on its way where a miniature device – or microchip – is pumped or dropped into the drill string and, acting like a robot, is capable of recording in-situ data and stores it on board the chip while travelling downhole, eventually returning to surface with the circulating drilling fluid.

Once recovered at the surface, the recorded data would be downloaded wirelessly for instant use at the rig site or transmitted back to an operation center.

After more than three years of challenging work by dedicated technologists in overcoming various technical, design, manufacturing and lab testing challenges, a prototype was ready for the first field test.

The industry's first field test of a drilling microchip was successfully conducted in a Saudi Aramco well.

"We are very pleased with the field test results," said AbdulHameed Al-Rushaid, Drilling & Workover general manager. "This could be a game-changer, and we would even like to accelerate the deployment of microchips in our fields."

The function test successfully proved the basic concept of the microchip system, a batch of seven mm prototypes, which travelled about 6.6 km in the 8-3/8 inch wellbore to a depth of 11,050 feet and returned to the surface successfully.

Meaningful and realistic data was retrieved from this environment for the first time and downloaded from the returned microchip that showed the dynamic bottom-hole pressure of 7,500 psi and circulating bottom hole temperature of 190 degrees Fahrenheit, consistent with static bottom hole pressure of 6,700 psi due to mud weight and wireline tool recorded static bottom hole temperature at 235 degrees. The field test also identified several areas for further improvements.

"This is an important milestone in the development of this technology," said Samer AlAshgar, manager of EXPEC ARC. "Not only are we looking to improve the integrity of the drilling microchips but also to increase their capabilities beyond pressure and temperature."

Currently, the primary function of the prototype microchip is to record in-situ mud temperature and pressure profile along the entire wellbore circulating path.

The current state-of-art fiber optical mini sensors are used as part of the data recording system, while the internal design of the on board chip is an open platform so that it can be adapted for many other mini sensors.

The next step will be to continue optimizing the microchips and further miniaturize the size while at the same time investigating the potential for various measurement sensors and optimizing the surface recovery method to achieve a commercially viable product in the near future.

SOURCE: Saudi Aramco