Improve CT Milling Operations with 20/20 Vision - Combined Downhole and Operational Data

Abstract

This paper will compare milling plugs with surface weight versus downhole weight and torque utilizing a real-time data platform to minimize unplanned, non-productive time (NPT) and cost overruns. The conclusive findings of this North American plug drillout operation highlights how pairing downhole weight coiled tubing (CT) operational data and visualizing this information in real time improve operations. The team performed a field study to determine the best approach to mill out plugs. They milled the first plugs using the company's standard operating procedures (SOPs), decisions on surface weight and circulating pressure, and then assessed the plug parts at the surface. After establishing a baseline, the company milled the remaining plugs using real-time downhole weight and torque, along with other essential operational data. The company assessed the plug parts once they all returned to the surface. This study will demonstrate the improved efficiencies and reduced risks provided by performing a millout with essential data in real time, compared to hoping for the best with limited data. When the CT operator used surface weight to mill plugs, weight on bit (WOB) fluctuated significantly, resulting in the mill generating large plug parts. Once the CT operator started milling the plugs with downhole WOB, the WOB range tightened, and torque was 50 to 250 ft-lbf. The ability to utilize downhole WOB in real time, along with the other CT data, will give all parties at the wellsite and in the office the best opportunity to mill out frac plugs successfully and consistently. Using downhole WOB and torque with all other CT data in real time helps limit downhole operational risks inherent to CT plug millouts. The ability to see the clear difference between milling out plugs using downhole WOB and torque versus surface weight in a real-time platform provides essential insight into how to reduce stuck pipe instances, increase efficiencies, and lower completion costs.