Ex d Master Control System for Offshore Structural Monitoring

JCE designed and manufactured a bespoke Ex d Master Control System for an offshore monitoring application on an oil platform in the northern North Sea.

The system was initially developed to support long-term pipework strain monitoring, providing a robust hazardous area solution capable of collecting valuable data under demanding offshore conditions.

Following installation and commissioning, the system began recording clean monitoring data immediately. During its first night in operation, it captured pipework strain data during conditions with a significant wave height of 6.5 meters. This provided an excellent example of the high value events the client had previously been unable to capture simply because monitoring equipment had not been in place at the right time.

The monitoring cabinets have since been deployed across other projects to measure structural and pipework strain simultaneously. They have also been integrated with smaller wireless gateway cabinets manufactured by JCE, adding wireless vibration monitoring and live remote access to the collected data.

Three of the larger monitoring cabinets have now been supplied and remain in continual use, demonstrating the adaptability and long-term value of the solution.

The original project required a dedicated hazardous area control system to support strain monitoring equipment installed on an offshore asset.

The monitoring system needed to remain operational for an extended period and provide reliable data collection within a challenging offshore environment. The electrical equipment therefore had to deliver dependable performance while meeting the technical and certification requirements associated with installation in a hazardous area.

JCE was tasked with supplying a bespoke Ex d solution incorporating the master HMI and associated barrier equipment within a single framed assembly.

As the project progressed, JCE worked closely with the project team to address final punch list items and respond to client technical queries. Some of these queries extended beyond the project team’s existing knowledge, with JCE providing the specialist support required to help bring the system through to successful commissioning.

JCE manufactured a Type 5953-EMCS Ex d Master Control System, comprising:

• 1 × Type 5954-EMHE Ex d Master Control HMI Enclosure
• 1 × Type 5955-EMCE Ex d Master Control Barrier Enclosure
• Purpose-designed support frame
• Integrated keyboard tray
• Complete assembly, interconnection and wiring to project drawings

The system was designed as a complete hazardous area monitoring assembly rather than as a collection of individual components. The Ex d enclosures provided the required protection for the electrical equipment installed within the hazardous area, while the barrier enclosure provided the interface between the monitoring instrumentation and the control system.

The master HMI provided the local operator interface for the monitoring system, allowing the collected data to be viewed and the monitoring equipment to be managed from the offshore installation.

A key aspect of the design was the integration of the HMI, barrier equipment, wiring and mechanical support structure into a single engineered assembly. This provided a compact and coherent installation while simplifying offshore installation and ensuring that the electrical interfaces were consistent with the project requirements.

JCE completed the mechanical assembly, electrical installation and wiring in accordance with the project documentation, supporting the system through manufacture, inspection and the final stages of commissioning.

Following installation, the first system was commissioned successfully and began providing clean pipework strain data from its first day in operation.

Its value was demonstrated almost immediately. During the first night, the equipment captured pipework strain measurements during conditions with a 6.5 m significant wave height.

On this project, wave height directly influenced the amplitude of stress within the pipework being monitored. The system subsequently captured conditions involving waves of approximately 8 meters and above, providing data from events the client had previously been unable to measure.

The information collected significantly reinforced the project team’s recommendations to its client and provided a clearer understanding of how the pipework responded during severe offshore conditions.

The flexibility and configurability of the cabinets have allowed them to be redeployed for a range of monitoring requirements.

While the first project focused on pipework strain driven by wave conditions, later applications have included the simultaneous measurement of structural and pipework strain. The systems have also been used to investigate resonance caused by pump running speeds, representing a very different source of excitation.

JCE has now supplied three of the larger master control cabinets, all of which have remained in continual use. On one offshore asset, two cabinets have been operated side by side to support the monitoring requirements of the installation.

The cabinets are rotated annually, allowing one unit to be returned to JCE for inspection and confirmation that it remains fit for continued service. This helps support reliable long-term operation while allowing monitoring activities to continue.

The larger master control cabinets have also been paired with smaller wireless gateway cabinets manufactured by JCE.

These gateway systems collect vibration data from wireless accelerometers, allowing vibration measurements to be combined with the structural and pipework strain data gathered by the larger cabinets.

The smaller cabinets also incorporate cellular modems, providing remote access to both monitoring systems through the offshore 4G network. This connection operates independently of, and is air-gapped from, the asset owner’s network, avoiding the IT and cybersecurity complications that can arise when connecting monitoring equipment to a client’s internal systems.

The project team can now access the monitoring data live as it is collected, improving visibility and allowing information to be reviewed without waiting for it to be retrieved from the offshore installation.

“Thanks to JCE for the efforts, especially towards the end of the project when the client technical queries came in. You really helped us out with getting it over the line. The quality of the completed installation has also received positive feedback from senior onshore management following a visit to one of the offshore platforms. The system was praised for its appearance and integration, with the installation described as looking like “it was always meant to be there”

Lionel Maciver
Senior Consultant Engineer

What began as a bespoke system for a single pipework strain monitoring project has developed into a flexible offshore monitoring platform supporting a growing range of applications.

Three larger Ex d monitoring cabinets are now in continual use, measuring structural and pipework strain across multiple projects. When paired with JCE’s smaller wireless gateway cabinets, the systems can also capture vibration data and provide live, air gapped remote access through offshore 4G networks.

The ability to redeploy and reconfigure the cabinets has enabled the project team to investigate very different operating conditions, from stresses associated with significant wave heights of around 8 meters and above to resonances driven by pump running speeds.

The project demonstrates JCE’s ability to combine bespoke hazardous area equipment, adaptable system design and responsive engineering support to deliver long-term monitoring solutions for demanding offshore applications.