A gas ball valve was leaking from the body on a live city gas network. Trained specialists completed the work on the live valve, with no shutdown and no excavation. The procedure arrested the gas leakage on the live valve.
Case study
Live gas leak on a city network arrested with no shutdown
A conventional repair had already failed. The engineered fix ran on the live valve.
The valve and its duty
A gas ball valve was leaking from the body on a live city gas network.
City gas networks run through populated areas, so shutdowns and excavation carry real disruption.
A body leak on live gas is an emergency, not a routine service item.
Every hour such a leak runs, gas is lost and risk builds around the site.
The line stayed in service, so any repair had to run on the live valve.
What had been tried before
A third party had tried a repair with ordinary putty. That putty had hardened over the body and the sealing points.
Ordinary repair materials are not designed for live gas service.
The failed attempt left the valve leaking and harder to work on.
The intervention
We inspected the valve in September 2023 and assessed the leak on site.
We proposed a specialised and higher-risk emergency procedure for live isolation, assessed case by case. The client accepted that proposal in writing before any work began.
Execution followed in February 2024 over three planned site days. The three days covered arrival, the execution itself and demobilisation.
Trained specialists completed the work on the live valve, with no shutdown and no excavation.
Three points define this intervention:
- The valve stayed live throughout the work, with the network in service.
- The procedure was specialised, higher risk and assessed case by case beforehand.
- Trained specialists carried out the work, with no shutdown and no excavation.
Higher-risk work is only offered where assessment shows it can be done safely.
We do not publish the method for this procedure.
We share that kind of detail in direct talks, not on the public site.
The outcome and the record
The procedure arrested the gas leakage on the live valve.
That outcome comes from our own same-day report of the work. The client had accepted the proposal in writing and processed payment after the job.
The root cause was assessed as a ruptured internal gasket in the flange area.
This page reports the outcome only, which is a deliberate choice for this case.
If you face a similar leak, start with the valve details, not the method.
See the field results from more live valve work across other settings.
Explore field services for emergency call-out support on installed valves.
Our live leak sealing guide explains when online sealing applies at all.
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Start with the valve condition
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