Through a series of examples, this study examines how real-time bottomhole data has reduced or mitigated the risks inherent to coiled tubing (CT) applications, leading to safer job execution. A number of tasks such as rigging up, mixing fluids, pumping, and rigging down are part of conventional CT interventions. Each of these tasks has risks associated with it. With the intent of optimizing CT operations, a fiber optic system was developed to enable real-time bottomhole measurements, allowing live monitoring of interventions. By providing real-time downhole intelligence, the technology has provided the means to operate more efficiently and enhanced the service quality and reliability of the CT services. More importantly, it helps optimize or minimize the tasks associated with conventional CT interventions, reducing personnel exposure to many of the risks. By providing a real-time casing collar locator (CCL), performing an extra dummy run is no longer necessary for all depth- critical operations. Reducing the number of runs not only reduces overall operational time, it also reduces personnel exposure to hazards related to these operations. Downhole pressure and temperature sensors have provided positive confirmation of gun detonation on CT perforating applications, reducing the risk of pulling out of hole with live guns. The monitoring of real-time bottomhole pressure provides a safer way to manage pressure by either assessing and obtaining the preferred perforating balance condition or validating the operation of the choke during a cleanout to avoid gas entry and to maintain a better control of the well. In applications such as matrix stimulations, cleanouts, or even nitrogen kickoff, the system has proven beneficial and effective in optimizing treatment volumes, consequently reducing extended cleanouts and associated flow back and flaring. Finally, this study evaluates the process of making informed decisions during execution of a CT job based on real-time downhole critical parameters and their impact on overall HSE performance.

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Technology Update Deeper boreholes and longer, more deviated laterals are driving an evolution in well intervention operations, opening opportunities for the industry to develop challenging wells in new frontiers as intervention capability expands to support the most complex wells and completions. From a service company standpoint, this phenomenon has challenged the industry to make continued improvements in the delivery of well intervention services and technologies to meet the needs of customers and do the job right, the first time. Development of advanced equipment, such as coiled tubing (CT) and other downhole tools that transmit critical data and measurements in real time, is helping operators move into these new arenas and produce from wells that once would have been inaccessible to intervention methods. By far the most used and exposed piece of equipment in the oil field, CT has been a critical tool in moving well intervention services forward. The need for accurate, real-time data in CT operations will continue to be a key driver for further innovation. Downhole tools that can provide real-time information on depth, pressure, and temperature and depth correlation are critically important and represent a significant change from the requirements of 10 or 20 years ago in shallow, vertical wells, where a 0.1% discrepancy was acceptable. For example, intervention in an offshore well of more than 20,000 ft requires better resolution and greater accuracy in the critical parameters, such as depth, pressure, and the specific activity of the CT than intervention in shorter wells in less challenging settings. In this situation, a stimulation treatment to increase the productivity of a well with lower drawdowns on the reservoir can take 2 or more days to run in and out of the hole. Traditionally, operators have used surface measurements to infer the depth from length measurements, with little information and control over what the CT is doing downhole. In a difficult horizontal well, reliance on those assumptions can very easily lead to discrepancies in measurements and inaccurate decision making. Schlumberger made a conscious decision more than 10 years ago to focus on developing high-tech sensors that provide real-time downhole measurements for greater accuracy. Today, tools that deliver the capability to digitally operate key well intervention services and equipment are aiding rig crews in conducting efficient, safer well interventions.