The Greenray group of companies have been established since 1981, and have been offering turbine package upgrades and maintenance services to the Oil & Gas and Power Generation sectors for more than 30 years. Our philosophy is to work with you, the operator, in order to increase the availability and reliability of your equipment. Reducing costly downtime and unscheduled outages is our priority.

Mature industrial gas turbines often require life extension and this can lead to a significant financial burden. The availability and reliability of your gas turbine plant and its increasing maintenance costs is sometimes an initiator to consider the replacement of machines. We can provide turbine package operators with a cost effective alternative to traditional service providers without compromising on quality, reliability and safety.

We refurbish your entire system, bringing equipment in line with modern certification and operational requirements, or we can put in place maintenance regimes that will improve your performance. This not only includes the gas turbine, but also the associated systems and plant. These can also be overhauled using the same processes: lubricating oil, instrumentation, filtration, exhaust and electrical systems that can all be repaired, serviced, refurbished or replaced.

Whatever your requirements, our experienced team of experts and field engineers have the technical knowledge to be able to offer you a comprehensive package of maintenance and support.

Gas Turbine Diagram


Maintenance, repair and overhaul

The Greenray group of companies has a network of established service centres, developed and built for the sole purpose of providing workshop and field service support for the maintenance and overhaul of gas turbine packages. Building on our parent company experience of designing, packaging and installing gas turbine power trains, we offer the full range of MRO services on a wide range of gas turbines within the power generation and mechanical drive sectors.

Our comprehensive range of services for aero-derivative and light industrial gas turbine packages are: 

  • Gas generator maintenance, repair and overhaul 
  • Power turbine maintenance, repair and overhaul 
  • Intake, filtration, enclosure and exhaust refurbishment and replacement 
  • Complete package or modular upgrade and modernisations 
  • On and off-sire service and maintenance of driven equipment 
  • Control System maintenance, calibration, upgrade and replacement
  • Gearbox maintenance, repair and overhaul 
  • Driven equipment maintenance, repair and overhaul 

Long-term maintenance contracts

When ad hoc maintenance is no longer compatible with your business operation, we offer customised preventative and corrective long-term maintenance contracts for your rotating equipment package, balance of plant and ancillary equipment that is critical in the operation of your gas turbine. Every contract is unique and based on discussions between you and our engineers, with the single objective of putting in motion a contract that delivers measureable benefits to the costs and operation of the plant.

Installation projects and commissioning

Our field service engineers have come from many different locations and have worked for some of the major OEMs. These highly skilled experienced professionals, combined with our technical engineering expertise, allow us to offer full installation, project management and commissioning of new and used gas turbine plants; from a simple commissioning of a mothballed gas turbine power generation unit to the full commissioning of a combined cycle power station, including all ancillary plant equipment required to operate the power station.

Supply of new equipment

We design, project manage, supply and install all aspects of the gas turbine plan. We supply new gas turbine packages from 1.6MWe to 66MWe. This supply can be from as little as machine specification through to full turnkey design, supply, installation and commissioning. Typical scope includes: 

  • Gas turbine and generator package 
  • Integrated control system 
  • Associated mechanical and electrical systems 

Package re-certification and emission testing

In a world where new legislation and standards are coming into force on a regular basis, combined with mature gas turbine packages being operated beyond their original design life, we offer our clients a recertification assessment for modification to components that are no longer supported or pose a HSE risk to the safe operation of the equipment. In addition, we have the ability to test and check the emission rating of your equipment to assist with calculation of carbon tax and emissions legislation.

Control systems and upgrades

The provision of system upgrades and retrofits is an important aspect of the operation of a gas turbine package or plant, it is the platform to improve operational reliability and remove unscheduled downtime. We offer complete controls upgrades that help to remove obsolescence issues with ageing components. Old components that cannot be supported present a risk to your continued operation, as the failure of a single key component could result in system shutdown with extended downtime awaiting an OEM engineered solution. Our engineering team and manufacturing facility can address these issues supplying a modern engineered and cost effective solution. 

Such a solution offers the following benefits: 

  • Designed using off the shelf rugged industrial components, which reduces inventory and improves spare part availability 
  • High Mean Time Between Failures (MTBF) statistics
  • Dual redundancy available
  • Access to software upgrades/improvements as the logic is not 'hard wired; 
  • Enhanced operational data and archiving
  • Improved operator interface with intuitive LCD touch screen displays
  • Integration into existing and new DCS and SCADA Systems, along with remote control and monitoring options.
  • Condition monitoring (ideally with instrumentation upgrades)
  • Different levels of parameter access (e.g. Operator/Supervisor/Maintenance)
  • HAZOP/FEED Studies and SIL 2 Capability
  • Incorporation of current design standard such as SIL 2 certification 

Life extensions and engineered solutions

There are a number of problems that frequently arise from old or obsolete parts no longer available for purchase, including unreliability, lack of parts availability, limited functionality and incompatibility with other upgrades. Our engineering team and manufacturing facility can address all of these issues and more, finding the right tailored engineering solution for your equipment.

Strategic planning

Capital spares and advanced maintence outage planning can seem complicated when managing multiple items of rotating equipment scheduled for maintenance during a plant shutdown. We provide a full maintenance plan for the outage, with resource demand graphs, required spare parts lists, general consumables and the preparation of contingency planning for unexpected discoveries’ during the maintenance outage. With our enhance supply chain and manufacturing capability, we can quickly prioritise sourcing and/or urgent manufacture of one-off parts to ensure your plant is returned to service as swiftly as possible.

Decommissioning and turbine relocation

Gas turbine equipment can often be surplus to requirements. We have the ability to take a complete power plant from one location to another, reengineering and modifying the equipment package to ensure it will operate efficiently and effectively in its new location. This includes reviewing your requirements for the power plant to operate under changed circumstances, such as in a different climate or location where the original design operating parameters are different.

Gas Compressors

Specialists in providing technical knowledge and engineering support for a wide range of mature gas compressor packages.

Plant Design Solutions

Gas, diesel and thermal solutions for power generation and mechanical drive applications.

For more information about ITS and our comprehensive range of services please contact us on +44 (0)1522 503300 or