This paper presents the design features and the results from field trials of a new wireline tractor developed specifically for through-tubing intervention into producing horizontal wells with barefoot completions. Many Middle East horizontal wells have barefoot completions in which the producing zone is left without tubulars. The vertical section is cased and production tubing put in place. Intervention for production logging or remedial work is challenging due to the need to pass through tubing and then operate in open hole. Intervention is conducted on coiled tubing or wireline tractors. Coiled tubing has limited reach in open hole due to higher friction, and it chokes flow through the tubing, resulting in inaccurate production logs. Conventional wheeled tractors apply stress that can destroy some formations at the wheel contact point. This leads to heavy slippage and extremely slow progress. Several technical innovations were implemented in the new tractor to overcome these challenges. A reciprocating mechanism drives a pair of linked grips with independent opening diameters to conform to variations in borehole geometry while providing a large contact area with the formation. The radial force is hydraulically amplified from the tractor load, enabling it to grip with as much force as required. Results from field trials show little to no slippage in conditions where previous tractors have struggled. The tractor features dual floating hubs that let it close in the uphole direction when tractoring to improve restriction navigation or close in the downhole direction while pulling out of hole to prevent self-locking. The combination of the dual floating hubs and a constant-force opening mechanism enables automatic navigation of restrictions and expansions where previous technologies would have required a manual open/close sequence. These innovations were successfully tested in several tractor operations. One case study is presented in which these features were instrumental in successfully getting to the bottom of the well and back to surface. In one case, the same well was logged using coiled tubing, a prior-generation tractor, and the new tractor. A comparison of these intervention methods is shown. The integration of a reciprocating tractor drive mechanism with novel technical solutions for linked grips, pad pressure regulation, constant force expansion, dual floating hubs mechanism, and automatic navigation has resulted in more reliable and efficient tractor operation in wells with barefoot completions.

Using steam injection to produce wells has been a common practice in Canada for several decades. Steam injected into the well causes heavy oils to flow more freely, increasing or even enabling production. There are several methods for stimulating a well with steam. A common practice is to drill two horizontal wells on a vertical plane and inject steam into the top well. This promotes oil flow to the bottom well, where it can be produced. The horizontal wells can have extremely high temperatures. As wells age, it may be necessary to revisit the steam injection strategy. Cost efficiency plays a role in these wells; thus, wireline is a good operations candidate. However, performing wireline measurements and services, such as perforating, in these wells can be difficult due to the high temperatures and challenging environments, such as in horizontal wells. New tractor technology enables wireline tractors to go into uncharted territory. Several jobs have been performed at temperatures above 175°C, which is the temperature rating for standard industry tractors. In some jobs, temperatures above 210°C have been reported. Logging while tractoring can obtain a temperature baseline as the tools are run in hole. From these temperature logs, injection profiles can be obtained for optimization. Pushing the limits of tractor technology facilitates the optimization of steam injection wells. High-temperature tractoring and logging while tractoring provide critical information for changing the steam injection strategy of older wells. The ability to perforate at high temperature is also advantageous because the steam injection does not have to be shut down for very long, if at all. The result is increased production efficiency and reduced downtime. This paper will describe a tractor concept that has been used successfully in steam injection wells.

This paper presents lessons learned from the design and field deployment of many different assets in sour environments. It will address the requirements and implications of design, operation, and maintenance of wireline intervention tools when exposed to H2S and CO2. Many wells in the world are drilled in fields with high concentrations of H2S and CO2. Even low concentrations of H2S put wireline tools designed from conventional downhole materials at risk of catastrophic failure through sulfide stress cracking (SSC), stress corrosion cracking (SCC), and hydrogen induced cracking (HIC). These wells are also highly corrosive, so even materials that are not highly vulnerable to these failure modes may suffer from extensive corrosion that still renders them unusable in these environments. Wireline intervention tools are at especially high risk of failure because the high loads they experience during normal operations preclude practices that might be standard in lighter-duty equipment like wireline logging tools. Wireline intervention tools that are intended for sour service should be designed from the beginning with corresponding requirements to avoid not only SSC, SCC, HE, and corrosion issues, but also any issues that may be related to the materials that are selected to avoid these failure modes. Materials capable of supporting high tensile forces in sour environments are extremely limited, and most of these are susceptible to galling. Care must be taken during the design to avoid situations where this galling would occur. Both H2S and CO2 are soluble in water to create weak acids, so the amount of water present is also an important factor when determining acceptable materials. Operation of wireline intervention tools in sour service environments must be carefully planned and executed. Proper cleaning and maintenance procedures are also critical to maintaining tool reliability and longevity following sour operations. Much historical wireline intervention design and material selection is based on tribal knowledge (i.e., unwritten knowledge and best practices). and standard ANSI/NACE MR0175/ISO 15156, Petroleum, Petrochemical and Natural Gas Industries—Materials for use in H2S-Containing Environments in Oil and Gas Production. Tribal knowledge is often suspect, and the application of the standard is difficult for wireline intervention equipment because factors other than cracking are important. This paper also moves beyond material selection to include guidance and best practices for mechanical design, operation, and maintenance of wireline intervention tools that are not directly addressed by NACE standards.

An instrumented, powered, and nonexplosive mechanical punching system with full surface control is presented to demonstrate the benefits and limitations of such systems versus traditional explosives and/or nonpowered mechanical punching systems. The paper will consider design criteria, performance, real-time outputs, flow areas, and operational risk factors when evaluating the different punching systems. The oil industry has run many forms of explosive and nonexplosive punching or perforating assemblies in wells over the years. As well design and complexity have changed over time, so has the need for punching and perforating methods. An instrumented and surface-controllable, nonexplosive mechanical puncher is the needed change in downhole punching and perforating methods for increasingly complex well designs. Such a system is seen as a safer, more reliable option than traditional methods, and it provides immediate feedback on the operation. Additionally, during punching operations, the system significantly reduces the risk of damaging control lines directly behind a tubular and eliminates the risk of damaging annular tubulars. Unique design factors and mechanisms were evaluated and characterized to develop an optimized instrumented and surface-controllable, nonexplosive mechanical puncher system. Puncher materials and geometries were evaluated for durability, forces required to penetrate a tubular, and flow areas generated. These punchers were characterized in multiple tubular sizes and grades to determine the relationships between tubular changes to changes in the same durability, forces, and flow areas. It was seen that different puncher types and tubulars have varying operational risks, durability, forces required to penetrate, and total flow areas generated. This information can be used to optimize a puncher to the operational objective. Additionally, through instrumentation, it was seen that there is repeatability in punches performed, and a successful "shot" and potential puncher wear can be determined. It was also seen that the system reduces risk in several areas. When compared to punching with explosives, there was no tubular swell at the perforations nor internal perforation burrs or damage. The system was punched directly into a downhole pressure gauge line behind the tubular with no damage observed to the external line after the punch hole was made. Finally, it was seen through surface control, powered options could be used to reduce any sticking risks. The novelty of the instrumented and surface-controllable, nonexplosive mechanical puncher system is in the engineering, design, and characterization of the system to provide an optimized, more reliable, and more efficient downhole punching system. In addition, there is value in knowing in real time the status of the operation, downhole diagnostics, and allowing of surface controls for risk management and additional contingencies.

This paper outlines the capabilities and advantages of a 3 1/8-in. instrumented wireline tool designed for fishing or shifting in casedhole wells with up to 90,000 lbf with high precision and minimized tubular deformation. Some fishing necks have ratings higher than maximum capacity for linear actuators of similar size. To maximize the pull force applied to the fish, it was necessary to intervene with a linear actuator with a capacity at least as high as the fishing neck, but without increasing diameter to the point that it did not fit in the tubing or through restrictions above the fish. It is additionally necessary to accomplish this high pull without damage to the tubular where the linear actuator reacts the force applied to the fish. This imposes a requirement on the anchor module to avoid applying excessive radial forces to the inside of the tubular. A linear actuator was designed that has proven a pull capacity of up to 90,000 lbf to fish stuck tools without exceeding a 3 1/8-in. tool diameter. This module can achieve this feat with precision measurements on the force applied to the fish, the displacement of the fish relative to the tubular, the radial force applied to the tubular by the anchors, and the exact opening position of the anchors. It also carries onboard temperature and pressure measurements to detect changes in wellbore parameters when used for exercising stuck ball valves or sliding sleeves. Extensive simulations have been completed to aid in operational planning and ensure anchor pads do not damage the wall of the tubulars. Multiple anchor modules can be run in series to further distribute radial and axial loads if needed for thin-walled tubing. The use of high-precision instrumentation and high-strength mechanical design enabled a linear actuator to accurately pull twice as much as similar linear actuators with the same physical dimensions. This allows wireline to complete fishing operations in casedhole wells that were previously inaccessible either because of force requirements or diameter constraints, surpassing coiled tubing capacity.