AVG - Actuated Gas Valve
AVG
Actuated Gas Valve
Today’s high performance and low emissions, larger gas turbines demand more than just reliable fuel control valve operation. They demand stable, fast and ACCURATE fuel flow control.
Building on Precision Engine Controls’ quarter century of electric fuel metering valve experience, the AVG (actuated gas valve) offers the latest, patented, valve actuator technology coupled with a contamination resistant, NACE compliant, high flow valve.
The PECC high force actuator is the heart of the system. This patented precision actuator positions the valve within ±0.001 inches and can travel at speeds up to 10 inches per second. Furthermore, the actuator develops up to 1000 lbf ensuring that most debris will be crushed and/or passed through the valve. The result is a repeatable, fast acting valve that allows a smooth, reliable turbine light-off and stable load control.
The actuator’s 120 VDC fully integrated digital electronics feature real-time health and data monitoring through an isolated, RS232 serial interface. Separate power and signal pigtail harnesses provide convenient electrical installation interface.
The actuator design is robust and highly reliable. The actuator contains a brushless DC electric motor with no mechanical linkages. Directly coupled to the motor is a precision ground, ball screw shaft that is lubricated for extended operation. A non-contacting resolver is integrally mounted to provide accurate position feedback.
The valve is balanced allowing smooth, fast valve operation over a wide supply pressure range (0 to 500 psig). The smooth flow through design results in superior flow performance, self cleaning and high turn down ratio. The high turn down ratio (140:1) allows operation over a wide range and low supply pressures. The AVG can handle fuel flows for 10 to 75 MW gas turbine engines.
All these features are contained in a compact package that eliminates pumps and tubing normally associated with hydraulic or pneumatic control valves. The AVG is ideally suited for upgrade of older industrial gas turbines.
U.S. Patent No. 6,392,322
Electrical Characteristics |
|
|---|---|
| Input Voltage | 120 VDC |
| Minimum Voltage | 80 VDC |
| Maximum Voltage | 160 VDC |
| Steady State Current | 300 mA typical / 5 A maximum |
| Peak Current | 12 A for 100 ms |
| Fuel Demand Analog Input | 4 to 20 mA |
| Fuel Flow Analog Feedback | 4 to 20 mA |
| Motor Current Feedback | 4 to 20 mA |
| Serial Interface | RS232/ RS485 Optional |
| FAULT & OVERTEMP Interface | Dry Contact Switch |
| Bandwidth | - 3 dB @ 6 Hz |
| Electrical Connections | 90 Inch Leads,Potted to 0.75 - 14 NPTF threaded conduit |
Mechanical Characteristics |
|
| Fuel Media | Natural Gas or other man-made gases 40-micron absolute,filtered,dry |
| Maximum Operating Pressure | 500 psig (34.5 Barg) |
| Proof Pressure | 750 psig (51.7 Barg) |
| Minimum Controllable Flow | 0.025 in2 |
| Maximum Controllable Flow | 3.55 in2 |
| Leakage Flow | <5 pph |
| Flow Accuracy | ±5% of point |
| Linearity | ±1% of full scale |
| Step Response (10% to 90%) | << 150 ms |
| Mechanical Connection | ASME B 16.5,Class 300 RF, 3.0 Inch |
| Dry Weight | < 190 lbs (86.2 Kg) |
Environmental Characteristics |
|
| Temperature Limits | Ambient: -40°F (-40°C) to +200°F (93°C) |
| Fuel | -29°F (-20°C) to +257°F (125°C) |
| Weatherproof | CSA Type 3 or IP65 |
| EMC | Per 89/336/EEC European EMC Directive |
| Certifications (Actuator Only) | CSA (Canada and US): Class I,Division 1, Groups B,C and D; T4 |
European Directive |
|
| Compliance | (CE Mark) EE x d IIB + H2; T4 94/9/EC ATEX 73/23/EEC Low Voltage Equipment (LVD) 98/37/EC Machinery 89/336/EEC Electromagnetic Compatibility (EMC) |
Materials |
|
| Valve Housing | Carbon Steel |
| Wetted Components | Stainless Steel,NACE MR0175 Compliant |
| Seals | PTFE and Viton® |
