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Abstract In order to reduce rig time during workover operations, a new electric line (e-line) mechanical pipe cutting tool was deployed rigless in four ERD wells in the Middle East. The 4-1/2" production tubing of several high deviation wells needed to be cut and pulled prior to a tubing change-out campaign, commencing February 2013. This particular mechanical cutter was chosen for its non-explosive design, where a rotating crown removes pipe wall by grinding, creating a smooth bevelled surface without shavings. This eliminates the need for a polishing trip, allows the pipe to be severed even when under compression, and leaves a cut profile in the well which is ideal for subsequently fishing. Also, this type of cutter incorporates a 'fail-safe' mechanism that prevents the tool from becoming stuck following the cut process, and the cutting crown design precludes the tendency for sticking, which is a major concern with other mechanical cutters. In January, 2013, a system integration test was conducted to determine whether a grinding face cutter could actually cut a pipe in compression. A jig was set up to provide 20,000 lbs of compressive force on a 4-1/2", 12.6 lbs/ft pipe. The cut was made in 36 minutes. The subsequent rigless operations on four wells resulted in six successful cuts, without the requirement for the pipe to be put in neutral weight or tension. The amount of compression at the cutting depth was unknown, but at least 10,000lbs, as per the packer setting procedures. A key benefit of mechanical pipe cutters is that they eliminate the use of explosives and chemicals which can pose HSE and operational risks, especially when simultaneous operations are being conducted. The transfer and handling of explosives may also cause additional logistical requirements and significant delays, as safety procedures are employed. In addition, this mechanical solution eliminates the need for dress runs, and tubing recovery is optimized from a rig time perspective. This paper will discuss the operational steps taken to make the pipe cuts, a description of the new pipe cutting tool and lessons learned to improve future operations.

Conventional methods used for downhole sand or debris cleaning have considerable investments in economic costs and time. Scheduling these activities to minimize production interuptions and to maximize unrestricted flow is a constant challenge faced by production and flow assurance engineers in the Oil & Gas industry. A sand and fill cleaning decision can be expressed as an optimization problem since its purpose is to maximize the production of the well to accomplish production goals at the end of a time period. This paper presents optimization algorithms applied in dynamic programming to help in scheduling cleaning interventions for wells in order to maximize the continuous production under physical, technical and economic considerations while minimizing the investment cost of the total operation. A strategy will be presented which takes into account mainly the fixed costs but also the variable costs and sensitivity analysis that allow the model to better approximate reality. The strategy considers three options based on the costs of cleaning with either electric line or coiled tubing technology; 1) to completely remove a given volume of sand, 2) to clean to a minimum acceptable level or, 3) not to clean and allow sand volume increases to continue. The cost to perform sand cleaning with a certain technology based on a mathematical function, considers the following requirements:the relationship between volume of sand produced per unit time, Vt (flow),(Vmax-Vmin) or the interval between Vmax in which production of oil is minimized and the Vmin for maximum production,the time horizon to perfom the sand cleanings, andPoints that make the operation unfeasible such as physical restrictions in the well or operator time/cost constraints. This paper will also present two cases demonstrating the strategy to schedule cleaning interventions that achieves a set production goal.

Recently, a solution has been developed to provide for milling of nipple profiles and other downhole hardware with electric wireline. A new milling bit and milling system for the wireline miller enables nipple profiles to be opened up in diameter to allow larger intervention products to be deployed, e.g. straddle packers and insert valves. Extensive testing was conducted prior to the introduction of this service to optimize the weight on bit and torque. The result was the development of a unique version of the hydraulic stroking tool to be combined with the milling tool to provide the controlled weight on bit.A major benefit of using the wireline milling system is the ability to provide precision milling without mobilizing coiled tubing (CT) or heavy surface equipment for circulating and handling fluids. Thus, there is no risk of damaging the reservoir from the circulating fluids. In addition, this kind of intervention can be performed more cost-effectively, involving less people, less heavy lifts and therefore, reduced HSE risks.The world's first milling of a nipple profile on wireline took place in Indonesia where the wireline miller was mobilized to enlarge the nipple profiles in 10 wells. The entire operation was performed in 20 operating days and well kills were prevented, which would have been necessary if executing the operation with a conventional method, such as on CT. Major benefits included minimal reduction in production levels, precision milling with zero cuttings left in hole and no labour-intensive requirement for CT or heavy surface equipment.As of December 2009, the ID of twenty (20) Super 13 Chrome nipples have been enlarged for one operator, without a miss-run related to the new milling system.This paper will discuss the technical aspects of this new milling system as well as present the field performance gained to date through a field test and two case histories.

With today's high rig operating costs, identifying areas where new technology can be used to improve efficiency and reduce rig-time is critical to many a project's financial success. In deep water regions, new intervention solutions that are not rig dependent are especially desirable. Electric wireline deployed interventions have been shown to offer both technical and financial benefits in mechanical manipulation of downhole hardware, such as isolation valves, in that they are faster to mobilize and execute, saving the operator several days in rig-time and deferred production compared to pipe conveyed methods. Many deep water completions use down hole isolation valves for temporarily closing off production while awaiting flowline connections for first oil. These isolation valves can be shifted open or closed through surface commands while a backup (contingency) allows the valves to be mechanically shifted. Failure of these valves can result in expensive delays to production with large rig time costs to intervene. Operators in the Gulf of Mexico, West of Shetland and West Africa have been pioneers in the application of wireline conveyed mechanical solutions for isolation valve contingencies. The contingency consists of an electric wireline hydraulic stroking tool to shift the sleeve open or closed. The wireline stroker is either wireline tractor conveyed in high angles or run with only the shifting tool attached in low angles. A new intelligent shifting tool is also available for opening and closing valves on command to avoid hang ups on downhole profiles that may occur with the conventional spring-loaded shifting tools.

A light weight intervention technique utilizing electric wireline has emerged as an alternative to existing well intervention methods. Tractor technology enables high speed, low HSE impact and a high degree of precision in production enhancing interventions in onshore and offshore wells. Wireline tractor technology eliminates the limitation on traditional wireline by extending the reach of the wireline into a high angle or horizontal part of the well bore, enabling access to the entire length of the well. Interventions in challenging conditions such as subsea, deepwater, extended reach, high-yield, heavy oil and deepwater are also enabled whether the hole angles are highly deviated or not. For instance, where slick line or coiled tubing (CT) operations below 20,000 ft can be risky and costly, tractor technology offers a time and cost-efficient alternative for valve manipulation, sand clean out and scale milling. Furthermore, interventions have been performed in high temperature wells (388°F), high pressure (>20,000 psi), ERD wells (>30K ft) and high deviations (130°) wells. Wireline tractor services can be mobilized in a matter of hours and only require a crew of from two to four people, depending on the operation. Transportation can be done in a helicopter to avoid the cost and time of mobilizing a full CT spread such as when cleaning and milling operations are performed without surface fluid handling logistics. Further, lightweight interventions with tractor technology combined with low surface impact left on the environment, allows mobilizations in eco-sensitive regions where heavy methods are not permitted due to the irreversible environmental damage that would be caused. This paper will present case studies where the HSE impact was significantly reduced by employing lightweight intervention techniques through tractor related mechanical services. One case will be a recent operation of milling barium sulfate scale on electric wireline and removing the cuttings in the same run in the hole. The second case will be milling out a cast iron bridge plug on electric wireline and the third will highlight the world's first wireline tractor intervention from a subsea intervention ship, which provided a much lighter solution for the operator.

Traditionally, deviated and horizontal wells have been challenging to service in a cost and time-efficient manner. Conventional technology requires large equipment to be mobilized and many heavy lifts in the offshore environment, sometimes with negative HSE consequences. New technology on electric wireline has made it possible to access the entire well regardless of deviation and lateral reach. Wireline tractors and new mechanical services can be mobilized in a matter of hours and only require a crew of two people for many applications. Transportation can be done by helicopter to avoid the cost and time of mobilizing a full coiled tubing (CT) spread with bottom hole assembly. Additionally, fuel consumption, emissions and fluid discharges are reduced and heavy lifts are eliminated for the offshore environment. Mechanical down hole wireline tools have also been developed to manage produced water. When wells produce up to 100% of water, mechanical tools can isolate the water to increase oil recovery. By reducing water entry at the source, the subsequent efforts and costs to address it are reduced along with the environmental risks. This paper will illustrate how HSE benefits can be achieved through several case histories. One case history will show how time and crew requirements can be reduced when a wireline tractor and milling system were deployed to remove 42 ft of barium sulfate inside two wellbores. The scale was removed from both wells in 12 days – the same time it would have taken a CT unit to mobilize and demobilize offshore. Costs were reduced by 60% and crew requirements were reduced from 23 to 12 people compared which reduced human exposure to risks offshore. Another case history will illustrate how produced water can be effectively reduced through e-line mechanical services. In an offshore well in Norway, a leak was detected in the tubing, which resulted in 85% water cut. A wireline tractor and stroker were applied to install two straddle packers in order to isolate the water-producing area. Water cut was reduced to 5% and oil production increased 800%.

Many subsea completions employ a down hole isolation valve for temporarily closing off production while awaiting first oil or flow line connections. These valves are designed to be opened or closed through surface pressure pulses in the fluid column to activate stored nitrogen in the valve housing. When a valve fails to activate as expected, a reliable contingency plan must be ready or the financial consequences can be large. With the use of electric wireline tractor technology, a contingency valve opening system allows malfunctioning isolation valves to be mechanically shifted with depth precision and controlled force. This method uses an electrically powered hydraulic stroking tool to shift the valve sleeve open or closed with a selected force of 10K - 30K lbs depending on the type of valve. The stroking tool is either tractor conveyed in high angles or run with only a shifting tool attached in low angles. A new intelligent key tool replaces the spring loaded shifter, to allow the system to be run "slick" and avoid hang ups on down hole profiles that can occur with the conventional spring loaded shifting tools. An electric line deployed solution is faster to mobilize, more precise in locating shifting sleeves and less expensive than alternative solutions. A review of case histories will prove these points. Also, pre-job planning, integrated team involvement, SIT and operational recommendations will be discussed.

In recent years, re-invention and development of electrical wireline mechanical applications, initially for high-angle well-access in conjunction with wireline tractors, has proven able to unlock value potentials by allowing interventions, previously thought impossible or cost prohibitive, even in low angle wells. Common denominators are remote-control, rig-less operations and documented large value-creations. The most recent advancement in this service category includes milling and drilling on wireline; a breakthrough within intelligent production optimization. With the ability to engage a wide variety of challenges downhole, this technology provides hitherto unseen possibilities to increase production quickly, efficiently and safely. Also representing new capabilities is the technology of transforming constant mechanical force independently of the wireline and depth/deviation of the well. The advantage here is that operations can be performed from a crane or mast unit with electric line and apply a pulling/pushing force capable of manipulating down hole production control devices in a controlled and repeatable manner. This paper will present innovative areas of recovering production through various case histories.

Sand accumulations in high angle wellbores inhibits production, plugs completions, erodes hardware and blocks access to downhole jewelry, such as valves and sliding sleeves. Bailing on sick line wire is the preferred, low cost method to clean sand and debris in vertical wells but slick line can not often reach in high angles. Conventional remediation methods for high angles use either Coiled Tubing or an expensive rig to remove sand and debris. This paper presents a rigless alternative to sand, debris or scale removal utilizing a combination of well tractor technology and a new vacuum/bailer system all conveyed on electric wireline. Tractor technology is a proven tool as a conveyor of services in high angle wells. Combining a tractor with a well cleaning system provides the means of accessing and removing debris either selectively in one run or over a general area in multiple runs. These electric line powered tools can be mobilized quickly with less crew, and for far less cost than a coiled tubing mobilization. Following the sand removal, evaluation of the source of the sanding problem can then be performed with E-line inspection services during the same rig up. Three case examples will be presented demonstrating the three different cleaning methods: liquid environment vacuum system, dry environment auger system and scale milling system. Each example will detail the unique cleaning head and bailer system used for the given completion and problem.

Wireline tractoring technology has set world and Gulf of Mexico records for several logging applications during the initial completion and intervention of two extended-reach, deepwater frac pack wells and one extended-reach, deepwater water-injection well. This paper reviews some of the challenges involved with conventional conveyance methods in extended-reach wells, describes the planning process for wireline tractoring operations, including prejob modeling, and summarizes the results of a project.The authors will also share the lessons learned and best practices implemented. Proper utilization of this technology has led to significant cost savings for the example project.