|A vital aspect of the Mission Critical Controls for gas turbines is fuel flow modulation. Turbine Controls Ltd listened to the difficulties experienced by gas turbine users and developed the Posiflow liquid fuel delivery system.
The system operates by using the flow versus speed characteristic of a positive displacement pump; i.e fuel delivery rate is directly proportioned to pump speed.There is a wide range of commercially available pumps capable of pumping the most aggressive fluids.TCL build systems to meet your specific requirements.
The proven features of positive displacement pumps and variable speed drives provide reliable, repeatable and accurate control.
Scope of supply
The pump and motor assembly can be supplied either as a standalone device or integrated into a liquid fuel skid. Standalone assembly would usually be supplied on a system where the other components required for fuel control are included in the existing installation. A fuel skid would be used when a complete fuel control system was required and would typically include shut off cocks, gauges, transmitters, filters and pressure switches.
- Flow modulation through pump speed control eliminates the need for a separate throttle,
- Hydraulically and chemically engineered for durability.
- Accurate and repeatable delivery pressure up to 300 bar.
- Flow rates up to 500 litres/min.
- AC and/or DC powered.
- System configuration option of tandem Pump.
- Pump only delivers the fuel required by the engine.
- Lower spares inventory with reduced component count & improved reliability.
- Low total life cost.
- Solutions for aggressive fuels such as Naptha.
- Reliable engine starting giving peace of mind and reduced operating costs.
- Zero calibration cost.
- There is a system to meet your
- Remote starting from batteries.
- Remove troublesome flow dividers, particularly useful on GE Frame engines.
- Energy and pump wear reduction.
Posiflow Systems have been supplied on a variety of gas turbines used in the power generation, oil and gas industries. In the following two examples significant improvements were achieved in revenues by improving the reliability of liquid fuel modulation.
PowerGen Twin Avon Gen sets
UK utility PowerGen fitted Posiflow skids on twin Avon generating sets at Kingsnorth and Grain power stations. The project involved the removal of the on-engine fuel pump and fuel control unit which were designed primarily for aero application. The system design was over 40 years old and the lack of repeatability resulted in the need for frequent adjustments. Start reliability was below 70% due to light-up problems and the balance of the two gas generators.
Posiflow gave immediate improvements. Initial commissioning was minimal. The units now fire up and start every time.
Petroleum Development Oman - TA1750 pump sets
State owned Petroleum Development Oman replace hydromechanical governors with Posiflow pumps on 1MW TA1750 oil-pumping unit at Sahma. Units are dual fuelled and run continuously. Production has to be maintained even in the event of malfunction of the gas forwarding plant. Start reliability on liquid changeover to Standby liquid fuel was very poor. By upgrading the liquid fuel system to Posiflow the units start and changeover every time.