After another full cycle of independent flange inspections carried out by Zulu Joint Integrity & Training Ltd, the trend we’ve been documenting since 2010 remains unmistakable: defects found in bolted flange joints by our teams are increasing year on year across all industry sectors including downstream oil/gas, petrochemical, chemical, pharmaceutical, power generation and utilities.
2025 (UK only – overseas data not included);
➡️ Number of bolted flange joints inspected (post-assembly inc. 100% load checking of bolts): 12744
❌ Number of defects found: 1810
❌ Average Defect rate: 14.2%
And these aren’t minor workmanship issues – they are high‑risk, process‑safety‑critical failures that would have resulted in loss of containment had they not been identified during independent inspection.
Loose bolts/missing bolts/incorrect bolt material, incorrect size/type gaskets/ missing gaskets/more than one gasket in the same bolted joint/cutting discs used as gaskets!!! flange misalignment, no lubrication….the list goes on…
Our long‑term inspection data since 2010 shows a steady rise in both the number of flanges inspected and the percentage of defects found. Despite industry standards and guidance, competency frameworks and decades of lessons learned, poor flange assembly practice is becoming more common, not less.
This is a process safety issue — not a maintenance task.
Bolted flange joint assemblies remain one of the most frequent leak points in industry, yet on times they are still treated as routine, low‑risk activities. Our findings demonstrate exactly why independent inspection, structured joint management, and competent assembly personnel are essential.
Zulu Joint Integrity & Training Ltd will continue to provide independent verification, competency development, and data‑driven insight to help industry close this gap. But the message is clear: we must collectively raise the standard of flange assembly and inspection before these defects become something far more serious.. 🔥 🔥
Zulu Joint Integrity & Training Ltd delivers focused compliance auditing and inspection controls that cut the risk of loss of primary containment — preventing the failures that escalate into accidents and environmental incidents. We’re ready to support you — contact our team.
Tel: 01656 523273
Email: info@zulujointintegrity.co.uk
