We present a new perforating technology based on new wireline conveyance equipment and advanced downhole modeling to maximize operational efficiency in long pay-zones under all pressure conditions. Results of perforating jobs of long pay-zones carried out on wireline in very short times compete with traditional Tubing Conveyed Perforation (TCP) operations which take much more time. Also, perforating jobs with large gun sizes that until recently were not possible in a single run with traditional wireline conveyance, are now efficiently executed in a single run. The new technology that allows conveying long lengths of perforating guns on wireline in a single run is based on four main elements: wireline systems with safe working loads up to 30,000 lbf, cutting-edge shock resistant mechanical weak points and disconnect systems, conveyance modeling, and an advanced transient dynamic modeling for perforating shock prediction. The perforating job design modeling is based on the reservoir zones and completion information, both a conveyance and a wellbore dynamics and shock simulation are carried out to determine the highest payload that can be more safely deployed per wireline run, and with the number of runs required, costs and risks are compared between wireline and TCP shoot and pull operations. For a well with a 750 ft thick pay zone, a North Sea operator requested a comparison between this new wireline perforating technology and conventional electric wireline deployment in terms of reservoir productivity, risks, and operational performance. For this well TCP was not considered due to reservoir and operational risks and challenges. Compared to the conventional electric wireline conveyance this new perforating technology offers better efficiency with only two wireline runs using a cable with 18,000 lbf of safe working load and a 10 Kpsi surface pressure control equipment compared to 6 to 8 conventional runs. The longest run consisted of 388 ft of 3 3/8″ guns, which was a new world record on wireline, with energetic liner charges and dynamic underbalance to ensure maximum perforation tunnel cleanup and well productivity. The total operational time for the perforating job was significantly less than conventional electric wireline, which translated into significant rig time savings. This paper demonstrates how the application of innovative technologies have minimized the risks of wireline conveyance with long and heavy perforating gun strings. We utilized well and reservoir information to design a more safe and reliable job execution, including prediction of perforating shock, tension profiles and wellbore dynamics. The new perforating technologies described in this paper have extended considerably the range of perforating jobs where wireline conveyance can be more efficient than traditional coiled tubing and tubing conveyed perforating.

Abandoning a well after it reaches the end of its life cycle requires a barrier evaluation operation across multiple strings. The traditional method for barrier evaluation requires exposing the outer casing by a cut and pull or section mill of the inner casing so that the outer casing can be logged, to verify the barrier seal. The cut and pull and subsequent inner casing/tubing recovery or section milling operations are costly and time consuming, often lasting for several days, thus increasing the overall plug and abandonment (P&A) cost and carbon emissions. This paper will describe a novel logging technology, allowing barrier evaluation of two strings simultaneously without the need to remove the inner string. The dual-string barrier evaluation technology is based on combining advanced ultrasonic multimodality physics with a multimodal deep-probing array sonic measurement providing the capability to map the axial and azimuthal material coverage in the first and second annuli simultaneously. The technology is applicable to evaluate tubing-casing dual-string or casing-casing dual-string environments. Based on the new technology, operators are no longer required to remove the inner string to evaluate the outer string. This approach revolutionizes conventional operations by reducing P&A rig days to minimize costs and overall carbon emissions. Furthermore, when proactively performing dual-string barrier evaluation offline or rigless in a number of wells marked for P&A, operators can use the log data to optimize future rig-based operations, minimize contingencies, and possibly prioritize the rig schedule for specific wells only. This paper discusses an offshore case study where the technology was used in two wells in the southern North Sea during the P&A phase. The measurements and observations with dual-string logging technology will be presented in addition to a validation exercise after pulling the inner string. These dual-string log measurements were subsequently used to streamline the abandonment program in realtime resulting in minimized rig time and scope, subsequently reducing overall carbon emissions. Even though the case study covers wells from a P&A operation, the dual-string technology is equally useful in other well scenarios such as sidetracks or even monitoring barrier integrity in production wells in long-term time-lapse well integrity monitoring. The technology can evaluate different types of barrier material such as cement or formation (shale/salt) squeeze or barite sag in both the first and second strings. Formation squeeze from specific North Sea shale (Williams et al. 2009) or salt members has been tested to act as a competent barrier.

Abandoning a well after it reaches the end of its life cycle requires a barrier evaluation operation across multiple strings. The traditional method for barrier evaluation requires exposing the outer casing by a cut and pull or section mill of the inner casing so that the outer casing can be logged, to verify the barrier seal. The cut and pull and subsequent inner casing/tubing recovery or section milling operations are costly and time consuming, often lasting for several days, thus increasing the overall plug and abandonment (P&A) cost and carbon emissions. This paper will describe a novel logging technology, allowing barrier evaluation of two strings simultaneously without the need to remove the inner string. The dual-string barrier evaluation technology is based on combining advanced ultrasonic multimodality physics with a multimodal deep-probing array sonic measurement providing the capability to map the axial and azimuthal material coverage in the first and second annuli simultaneously. The technology is applicable to evaluate tubing-casing dual-string or casing-casing dual-string environments. Based on the new technology, operators are no longer required to remove the inner string to evaluate the outer string. This approach revolutionizes conventional operations by reducing P&A rig days to minimize costs and overall carbon emissions. Furthermore, when proactively performing dual-string barrier evaluation offline or rigless in a number of wells marked for P&A, operators can use the log data to optimize future rig-based operations, minimize contingencies, and possibly prioritize the rig schedule for specific wells only. This paper discusses an offshore case study where the technology was used in two wells in the southern North Sea during the P&A phase. The measurements and observations with dual-string logging technology will be presented in addition to a validation exercise after pulling the inner string. These dual-string log measurements were subsequently used to streamline the abandonment program in realtime resulting in minimized rig time and scope, subsequently reducing overall carbon emissions. Even though the case study covers wells from a P&A operation, the dual-string technology is equally useful in other well scenarios such as sidetracks or even monitoring barrier integrity in production wells in long-term time-lapse well integrity monitoring. The technology can evaluate different types of barrier material such as cement or formation (shale/salt) squeeze or barite sag in both the first and second strings. Formation squeeze from specific North Sea shale (Williams et al. 2009) or salt members has been tested to act as a competent barrier.