Abstract
Real-time monitoring of downhole location, pressure, and temperature is currently available for many coiled tubing (CT) operations. A newly-developed tension, compression, and torque (TCT) data monitoring capability in real-time improves operational efficiency and accelerates well recovery in all types of CT operations. From milling, stimulation, and well cleanouts to gas lifting, camera services, logging and perforating operations, this intelligent coiled tubing (ICT) system can provide accurate, real-time downhole monitoring of high-resolution depth correlation, differential pressure and temperature, and TCT data.
The real-time ICT system consists of a 1/8-in. non-intrusive electrical conductor wire inside the carrying CT, surface hardware and software, and three versions of bottomhole assemblies (BHAs) in different sizes: 2 ⅛-, 2 ⅞-, and 3 ½-in. Each BHA incorporates a conductor release assembly, a casing collar locator (CCL), pressure, and temperature sensor package, and a BHA release function. In addition, a new TCT assembly has been developed for the 2 ⅞-in. BHA. Switching between applications is as simple as changing out the BHA, which reduces the need to rig-up and rig-down and leads to operational time and cost savings. The main advantage of this system is that it eliminates the downhole uncertainties so the CT field crew can react to changing conditions, making decisions based on dynamic downhole events and eliminating missed or wasted runs.
Several case studies have been recently presented (Livescu et al. 2015a,b) using the 2 ⅛-in. BHA. They involved ICT conveyed camera operations; complex cement milling, cleanout, and perforating operations; inflatable plug setting operations for water zone isolation; complex drifting, logging, jetting, zonal isolation, and scale removal operations; and matrix acidizing operations. In this paper the new TCT assembly development and testing are presented showing that combining the TCT data with location, pressure, and temperature data in real-time may increase the job efficiency and control. The new capabilities are important for the differentiation between frictional lock-up and potential obstruction tagging; the effectiveness of extended reach technologies such as fluid hammer tools, tractors, and lubricants related to the weight on bit (WOB); the confirmation of jar activation during fishing jobs; and the milling effectiveness over time, quantifying the mill aggressiveness from the back torque and WOB analysis. In addition, the new TCT data could be used to post-job validate in real-time the pre-job tubing force analysis (TFA).
