SAP B Leak Detection – An operator led multi-technology trial

Sustained B-annulus pressure (SAP B) is one of the most complex well integrity challenges in our industry. So, we’re pleased to share the findings of an operator’s multi‑technology trial which included the use of Fli in diagnosing SAP B pressure across three land wells in the UAE.

Conventional single-point diagnostics often struggle to pinpoint low‑rate, low‑pressure leaks, as this relies on being in the right place at the right time, potentially leading to missed events, lengthy rig time, costly workovers and uncertainty around remediation success.

The study set out to answer a simple but critical question: Which modern distributed sensing or acoustic technologies can reliably diagnose SAP B in real world conditions? Across the trial all technologies demonstrated clear improvements over conventional noise and temperature logs, however Fli’s bare fibre sensing excelled in conditions where:

• ✳️ High sensitivity is required to detect low pressure, low-flow and intermittent leaks behind tubing, casing and cement
• ✳️ SAP B is suspected to originate from reservoir related pathways
• ✳️ High‑fidelity depth‑continuous data and second-by-second insight is required to build a complete picture across the full wellbore
• ✳️ Rapid, ultra-lightweight mobilisation and rigless deployment are priorities.

Importantly, the study reinforces a broader shift in well diagnostics, particularly where signals are weak and flow is intermittent. It demonstrates that conventional snapshots are not enough for SAP B diagnostics and distributed sensing isn’t just “nice to have” – it’s essential!

🔗 Read the full SPE-230220-MS paper presented at ADIPEC in November 2025: https://onepetro.org/SPEADIP/proceedings-abstract/25ADIP/25ADIP/D041S139R001/793758

At WellSense, we’re committed to providing the right answers and working in partnership with operators, service providers and alongside other technologies to advance the industry’s ability to diagnose and remediate complex integrity challenges. Thanks to our partners (WIS) Wellbore Integrity Solutions for supporting this trial.

📩 Get in touch if you’re exploring SAP B remediation or considering diagnostics for challenging wells – we’d be glad to support your next evaluation: info@well-sense.co.uk