Background: Centrica's joint integrity challenge
Centrica Energy Storage operates some of the UK's most critical gas storage infrastructure, including the Rough field — the largest gas storage facility in Britain. Across their portfolio of offshore and onshore assets, Centrica manages thousands of flanged joints in hydrocarbon and high-pressure gas service, each representing a potential leak path if not correctly assembled, maintained, and tracked.
Like many operators of mature assets, Centrica had accumulated a joint population that had grown incrementally over decades of maintenance activity. Records were held across multiple systems, make-up procedures were not consistently documented to a single standard, and there was no reliable way to confirm — across the full population — that every joint had been assembled by a competent individual using calibrated tooling and the correct specified bolt load.
Following a regulatory focus on hydrocarbon release prevention and an internal review of their pressure systems management approach, Centrica made the decision to establish a formal, software-supported joint integrity management programme across their operations.
The approach: building a complete joint register
The first phase of the programme was a systematic survey of all flanged joints in scope across Centrica's assets. This was not a simple exercise. On a mature facility, joints are located in congested areas, at height, subsea, and in locations that had not been formally inspected for years. Each joint needed to be identified, tagged, and entered into the register with its location, service fluid, operating conditions, and the specified assembly procedure.
Elisian's Joint Integrity module was used to build and manage the register. Each joint was assigned a unique identifier linked to a QR code tag on the physical asset, allowing operatives in the field to pull up the full joint record — including the make-up procedure, bolt specification, and history of previous work — directly on a mobile device without returning to the control room.
The register was structured to capture:
- Joint location and P&ID reference
- Service fluid, operating pressure and temperature
- Specified bolt size, grade, and quantity
- Gasket type and material specification
- Target torque or bolt load and lubrication requirements
- Joint class and associated competency requirements
Connecting the permit system to the joint register
One of the critical gaps in Centrica's previous approach was the absence of a reliable link between the permit to work system and joint integrity records. When a joint was broken for maintenance, there was no systematic process to ensure that the correct make-up procedure was retrieved, that the operative held the required competency for the joint class, or that the result of the assembly was recorded against the joint's history.
With Elisian's Joint Integrity module, joint break permits are raised directly against the joint register record. The permit workflow enforces the following checks before work can proceed:
- The operative assigned to the joint assembly holds a valid competency certificate for the relevant joint class
- The torque wrench or hydraulic tensioning equipment allocated to the job has a current calibration certificate
- The specified make-up procedure has been retrieved and confirmed by the operative
At close-out, the operative records the actual torque or bolt load applied, any deviations from the specified procedure, and the result of any post-assembly inspection or leak test. The permit cannot be closed without this information being captured, creating an unbroken chain of custody from work request to confirmed reinstatement.
Competency management and tooling control
Two areas that are consistently identified in joint integrity incident investigations — and consistently undermanaged in paper-based systems — are operative competency and tooling calibration. Centrica's implementation addressed both within the same platform.
A bolted joint competency framework was configured in Elisian's Joint Integrity module, defining the training and assessment requirements for each joint class in scope. Operatives and contractors are assessed and their competencies recorded in the system. The permit workflow automatically checks competency status and prevents work being assigned to individuals whose certification has lapsed or does not cover the relevant joint class.
Calibrated torque wrenches and tensioning equipment are tracked as assets in the system, with their calibration certificates, calibration dates, and expiry dates recorded against each tool. A tool cannot be selected for use on a live permit if its calibration has expired. This removes a common failure mode where out-of-calibration tooling is used on critical joints without anyone involved in the work being aware.
Outcomes and regulatory position
Following implementation, Centrica's operations team had — for the first time — a complete, live view of the joint population across their assets, including the status of recently disturbed joints, the history of make-up activities on each joint, and the current competency status of all individuals authorised to carry out bolted joint work.
From a regulatory perspective, the programme provides the evidence base that PSSR 2000 compliance requires: a documented management system for pressure system components, controlled work execution by competent persons using calibrated equipment, and a full, searchable record of all maintenance activity that is available for inspection without manual retrieval from paper files.
The data captured through the system also enabled a level of trend analysis that had not previously been possible. Recurring issues on specific joints, patterns of gasket failures in particular service conditions, and joints that had been disturbed repeatedly within short periods all became visible — allowing the engineering team to identify and address systemic issues before they produced a release.
Key lessons for operators considering a JIM programme
Centrica's experience highlights several principles that apply broadly to operators establishing or maturing a joint integrity management programme:
- Start with the register. A JIM programme is only as good as its underlying data. Investing in a thorough, accurate joint survey at the outset pays back significantly in programme effectiveness.
- Connect JIM to PTW. A joint integrity register that is not connected to the permit to work system will not reliably capture what happens to joints during maintenance. The link between the two systems is what makes the programme a genuine management system rather than a database.
- Enforce, don't just record. Software that allows non-compliant work to be recorded after the fact provides an audit trail but not genuine control. The value is in enforcement at the point of work — preventing uncertified operatives or uncalibrated tools from being used before the work begins.
- Use the data. The information captured through a digital JIM system is an asset. Regular review of trends, repeat failures, and deferred close-outs should be part of the programme governance, not an occasional exercise.
Find out more
Elisian's Joint Integrity module is deployed across UKCS and international operations managing tens of thousands of flanged joints in hydrocarbon and high-pressure service. If you are looking to establish or improve your joint integrity management programme, speak to the Elisian team about how our solutions can support your specific asset and regulatory context.