When replacing or upgrading a control system, often there is a need to update or replace the fuel control system. The original fuel control systems are usually electro-hydraulic and connect to the gas turbine via a network of high pressure hydraulic lines, giving rise to many leakage paths and failure points. 

Even in optimum condition the skills required to keep this type of system in proper calibration and operation are difficult to come by and spare parts availability and servicing is also problematic.

By using latest technology and sympathetic design, we have engineered a direct replacement gas fuel system with the same fit, form and function as the original GEC Gas Fuel Cabinet.

The design brief was to minimise outage time and modification to existing site pipework if replacing a GEC Fuel Cabinet, with the same interface connection points within the same footprint.

By using pneumatically actuated fast acting double shut-off valves with intermediate vent and an electronic actuated fuel metering valve, the requirement for hydraulic actuation or control is removed. All the redundant hydraulic lines can be removed and capped off, eliminating sources of leakage. All additional instrumentation is built onto the fuel system, hence the fuel control is self-contained and self-regulating, requiring only a stable non-regulated fuel supply.

The modular nature of this design means it can be easily adapted to suit non-GEC gas turbines.

Liquid fuel systems on legacy gas turbines also generally rely on engine-driven high pressure pumps and actuators, which are usually worn beyond repair and expensive to replace.

Using an electrically driven positive displacement pump combined with variable displacement control the Greenray liquid fuel system does away with many of the possible calibration, leakage and control issues usually associated with the original liquid fuel systems. With minimal additional components the possibility of leakage and failure is vastly reduced over the original fuel systems. As fuel pressure is no longer dependant on gas turbine speed under starting conditions better fuel atomisation and therefore ignition is guaranteed.

Modular Gas Fuel System

  • Standard modular size – direct replacement for GEC Gas Fuel Cabinet.
  • Lower maintenance costs due to reduced parts count.
  • Pneumatic “double block and vent” shut-off valves.
  • Electronically controlled and actuated fuel metering valve.
  • On-board instrumentation – self-contained solution with built-in diagnostics.
  • Self-compensating for variable gas pressures – fully regulated fuel supply not necessary.
  • Industry proven technology.
  • Compliant with latest regulations – ATEX, Pressure Equipment Directive etc.

Variable displacement Liquid Fuel System

  • Reduced component count – less leakage paths.
  • Combined high pressure pump and metering assembly – Low fuel supply pressure requirements.
  • Industry proven design and components – robust proven design.
  • Improved ignition capability – complete control of fuel delivery pressure at all parts of the operating range.
  • Minimal instrumentation overhead – system is self-contained.