The petroleum industry is performing extensive research into rectifying structural well integrity issues, mainly caused by migration of hydrocarbon fluids to surface through microchannels, due to poor cementation, resulting in the inability to provide integral barriers in the 9⅝″ casing × 12¼″ hole annulus. As a consequence, the well life can be extended and the older wells can be restored back to production and injection, resulting in long term fulfilling of the increasing global demand for additional energy requirement. Annulus-B Remediation using HydraWell Technology is one of the innovative approaches that can be utilized in wells to provide strong integral cement barriers behind the 9⅝″ production casing to prevent reservoir fluids migrating to surface. This approach is gaining increased popularity due to a number of economic and environmental advantages such as restoring the well production/injection with minimum workover costs and risk due to less complex operations, mitigate environmental concerns by avoiding excessive steel cuttings like section milling and eliminating the complexity associated to re-entry risk as incase of section milling. The research utilizes a novel technology to execute a repair of wells with failed Annulus-B barrier integrity by providing integral cement barriers in the 9⅝″ × 13⅜″ casing annulus above the reservoir for wells experiencing migration of hydrocarbons from reservoir through the 9⅝″ × 13⅜″ casing annulus. The planned methodology starts with completion recovery followed by running noise, temperature and cement bond logs in order to evaluate the cement quality behind 9⅝" casing above the reservoir. Findings from the noise/temperature logs and oil sample evaluation indicated that oil is migrating from the reservoir, through 9⅝″ × 13⅜″ casing annulus, dripping at surface through the 30″ conductor pipe. The cement bond logs indicate poor cement behind 9⅝″ casing above the reservoir. Therefore, Remediation technology was successfully utilized as it delivers effective jet washing and subsequent cleaning of the annular space using specialized tools and thereafter spraying cement to create a 100-feet competent cement barrier behind the casings for effective isolation and the prevention of pressure communication to the surface via Annulus-B. Furthermore, a 7″ short tie-back was installed over the perforated cemented interval. Hence, the 9⅝" casing was re-established as a well barrier element in the well, allowing the injection rate for the well to be restored. This strategy may be developed as a very cost effective technology as it saves the operator approximately 5-8 days per well with associated significant CAPEX and OPEX savings by avoiding additional costs associated with complexity of operations in section milling. It is feasible to be applied in offshore wells requiring remediation of failed Annulus-B integrity with reduced rig time and the associated costs with minimum environmental risk.

Servicing oil and gas wells requires their integrity assessment both during operation and before abandonment. One of the main objectives in well integrity analysis is the location of metal losses in tubing and/or casing caused by corrosion, erosion or other types of pipe damage. The first three metal barriers (normally tubing, production casing and intermediate casing) are of the most interest to the industry. Dual string completions is an additional complication to through-tubing assessment of the second and third barriers.Magnetic Imaging Defectoscope (MID) is an electromagnetic scanning tool that recor ds magnetisation decays induced by high-power electromagnetic pulses. Metal pipe barriers contribute to magnetisation decays at different times depending on their diameters, which makes it possible to differentiate each of them and determine their individual thicknesses. Thickness determination requires the numerical finite-element modelling of each recorded magnetisation decay and iterative fitting of the properties and thickness of every metal barrier to the actual tool readings. A data array can store hundreds of thousands decays, and the data processing optimisation loop therefore requires parallel computing with multi-core processors to process data within a reasonable time frame. The MID hardware and interpretation algorithm have been tested on multiple laboratory stands simulating various downhole multi-barrier completions from 2-7/8Љ up to 13 3/8Љ pipes with artificial defects of various shapes and sizes ranging from 7 mm to 140 mm. This paper presents laboratory results and three selected field cases demonstrating the application of Magnetic Imaging Defectoscopy (MID) in single-string and dual-string completions for thickness evaluation of three barriers independently by a memory through-tubing survey.• Well W-01 with metal losses found at the same depth in the second and third barriers, i.e. 9 5/8Љ and 13 3/8Љ casings • Well W-02 with metal loss found in the second barrier, i.e. 9 5/8Љ casing, in an interval containing two strings. This corrosion has been confirmed by a repeated MID survey after pulling out the completion • Well W-03 with through-hole metal loss found in the second and third barriers, i.e. large-diameter 9 5/8Љ and 13 3/8Љ casings, through a 7Љ liner. This through-hole corrosion has been confirmed independently by High-Precision Temperature Logging and Spectral Noise LoggingThe above metal losses have been located by through-tubing memory surveys in offshore wells that were to be abandoned. The results of the MID surveys were then used to design environmentally safe abandonment procedures.

Increasing global demand for additional energy requirement - forecasted to increase up to 74% by 2030 - has catalyzed the petroleum industry to perform extensive research into rectifying structural well integrity issues in order to extend the life and return older wells to production and injection. These issues are mainly caused by failure of corroded surface casing. Due to the inability to provide integral barriers in the 95/8″ casing x 12¼″ hole annulus, these wells are planned to be abandoned or completed as single zone wells. Perforate, Wash and Cement remediation strategy is one of the innovative approaches that can be utilized in wells to provide strong integral cement barriers behind the 95/8″ casing to prevent reservoir fluids migrating to surface. This approach is gaining increased popularity due to a number of economic and environmental advantages such as reduction in costs for abandonment of current wells and drilling of new wells, mitigate environmental concerns, restoring the well production/injection with minimum workover costs and eliminating the risk with section milling of not being able to re-enter the casing. The research utilizes a Novel Remediation technique for providing integral cement barriers in the 95/8″ x 133/8″ casing annulus above the reservoir for wells experiencing migration of hydrocarbons from reservoir through the 95/8″ x 133/8″ casing annulus. The planned methodology starts with completion recovery followed by running cement, noise, temperature and corrosion logs in order to evaluate the cement quality behind 95/8″ casing above the reservoir and the corrosion level for 133/8″ casing. Findings from the noise/temperature logs and oil sample evaluation indicate that oil is migrating from the reservoir, through 95/8″ x 133/8″ casing annulus, dripping at surface through the 30″ conductor pipe. The cement bond logs indicate poor cement behind 95/8″ casing above the reservoir. However, the results from Metal thickness detection logs indicate low corrosion (~10-15%) in the 133/8″ casing, eliminating the necessity for any external casing patch to restore 133/8″ structural integrity. Therefore, Perforate, Wash and Cement remediation strategy was successfully applied and the integrity of the dual water injector well was restored by placing 100-feet cement barrier behind perforations in the 95/8″ casing above the reservoir. In addition a 7″ short tie-back was installed over the perforated cemented interval. Hence, the 95/8″ casing was re-established as a well barrier element in the well, allowing the injection rate for the well to be restored. This strategy may be developed as an economic saving technology as it saves us approximately 5-8 days per well with associated significant CAPEX and OPEX savings by avoiding additional costs on section milling and solving problems encountered with section milling. It is feasible to be applied in offshore wells having integrity issues as it extends the life of the well without taking on additional environmental risk.

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The petroleum industry has made significant investments and extensive research to rectify structural well integrity issues, one particular failure mode relates to the migration of hydrocarbon fluids to surface through microchannels, due to poor cementation, resulting in the inability to provide integral barriers in the 9%" casing × 12¼" hole annulus; therefore, these wells are being abandoned. Section milling and external casing patches are two of the widely-utilized approaches to restore annulus integrity; however, they add complexity associated with excessive steel cuttings and re-entry risk. Annulus-B Remediation using HydraWell Technology is one of the innovative approaches that can be utilized in wells to provide strong integral cement barriers behind the 9%" production casing to prevent reservoir fluids migrating to surface. As a consequence, the well life can be extended and the older wells can be restored back to production and injection. This approach is gaining increased popularity due to a number of economic and environmental advantages such as restoring the well production/injection with minimum workover costs and risk due to less complex operations, mitigate environmental concerns by avoiding excessive steel cuttings like section milling and eliminating the complexity associated to re-entry risk as incase of section milling. The research utilizes a novel technology to execute a repair of wells with failed Annulus-B barrier integrity by providing integral cement barriers in the 9%" × 13%" casing annulus above the reservoir for wells experiencing migration of hydrocarbons from reservoir through the 9%"× 13%" casing annulus. The planned methodology starts with completion recovery followed by running noise, temperature and cement bond logs in order to evaluate the cement quality behind 9%" casing above the reservoir. Findings from the noise/temperature logs and oil sample evaluation indicated that oil is migrating from the reservoir, through 9%" × 13%" casing annulus, dripping at surface through the 30′ conductor pipe. The cement bond logs indicate poor cement behind 9%"  casing above the reservoir. Therefore, the aforementioned remediation technology was successfully utilized as it delivers effective jet washing and subsequent cleaning of the annular space using specialized tools and thereafter spraying cement to create a 100-feet competent cement barrier behind the casings for effective isolation and the prevention of pressure communication to the surface via Annulus-B. Furthermore, a 7" short tie-back was installed over the perforated cemented interval. Hence, the 9%" casing was re-established as a well barrier element in the well, allowing the well’s injection rate to be restored. This strategy may be developed as a very cost-effective technology as it saves the operator approximately 5–8 days per well with associated significant CAPEX and OPEX savings by avoiding additional costs associated with complexity of operations in section milling. It is feasible to be applied in offshore wells requiring remediation of failed Annulus-B integrity with reduced rig time and associated costs, resulting in minimum environmental risk.