In today’s low global oil price environment, maintaining wells in operable condition while minimizing repair costs has become a critical economic priority for operators.
RML has long provided proven technical solutions to address well integrity challenges in 7-inch (177.8 mm) and 9 5/8-inch (244.5 mm) casing strings. These systems have demonstrated reliable performance in wells with high temperatures and elevated hydrogen sulfide (H₂S) content, delivering consistent results in demanding operating conditions.
New Solution Developed for 6 5/8-Inch Casing
At the request of a new partner, RML expanded its technology portfolio to address casing integrity issues in 6 5/8-inch (168.3 mm) casing strings. Bench testing of the new sealing elements was conducted in late 2025.
A key consideration during development was the operating profile of the customer’s wells, which are characterized by low temperatures and a high gas factor. To optimize overall repair costs, RML intentionally moved away from high-cost, high-temperature sealing materials and instead focused on materials better suited to these specific conditions.
Testing, Optimization, and Validation
Initial testing identified areas requiring refinement, including material re-selection and optimization of the setting mechanism angles. Following these adjustments, subsequent tests confirmed:
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Full and consistent expansion of the sealing elements
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Stable mechanical performance
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Successful pressure testing, validating reliable sealing capability
These results confirmed the readiness of the solution for field application.
Availability Starting in 2026
As a result of this development program, beginning in 2026, RML will offer both Surface Casing Patch and Casing Patch solutions for the following casing sizes:
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6 5/8-inch (168.3 mm)
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7-inch (177.8 mm)
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9 5/8-inch (244.5 mm)
This expanded offering will be available to both new and existing customers, providing cost-effective, field-proven options for addressing casing integrity challenges across a wider range of well designs.


