How are turbine engine igniters operationally checked?
Check System Operation The igniter can be checked by listening for a snapping noise as the engine begins to turn, driven by the starter. The igniter can also be checked by removing it and activating the start cycle, noting the spark across the igniter.
What are the common problem of a gas turbine?
Gas turbine engines may be affected in a number of ways, including: (a) increased deterioration of seals and bearings, (b) increased operation under low load conditions giving rise to the risk of blade flutter and fatigue damage, (c) increasing amounts of fatigue damage due to more frequent starts, load fluctuations …
What causes ignition in a gas turbine?
Most gas turbine engines are equipped with a high-energy, capacitor-type ignition system and are air cooled by fan airflow. Fan air is ducted to the exciter box, and then flows around the igniter lead and surrounds the igniter before flowing back into the nacelle area.
What is the purpose of ignition exciter?
Ignition Exciter System (IES) convert electrical energy at low voltage levels into high intensity sparks capable of firing an air fuel mixture in gas turbines. Generally, electronic switches are in series with the energy discharge path of the spark current.
How does a gas turbine ignition system work?
There are three components of a turbine engine ignition system: the exciter, the ignition lead, and the igniter. The exciter takes input current from the aircraft electrical system, steps up the voltage, and delivers a high voltage output signal through the ignition lead to the igniter.
What is the function of the igniter plugs in a turbine engine?
The exciter discharge is conducted through the ignition lead to the igniter plug where a spark is created that ignites the fuel/air mixture. Because engine combustor designs vary greatly, exciter discharge circuitry can be very complex.
What failure is most likely to occur in a gas turbine blade operating at a temperature of 950oc?
High temperature hot corrosion is also known as Type I corrosion, which occurs in the approximate temperature range of 825°C to 950°C (Meher-Homji). Figure. 1 shows the micro-structure of the surface of the turbine blade material near the tip which has suffered from the hot corrosion.
How many igniters are in a gas turbine engine?
How Many Igniter Plugs Are There In Gas Turbine Engine? Each of the two igniter plugs is a separated unit which generates sparks during the engines operation. The spark is produced continuously until the engine start.
Do turbines have spark plugs?
Do Turbine Engines Use Spark Plugs? Yes. If there are two or more combustion cans connected to a gas turbine, the spark plug is retractable. It may be worth noting that on 18 engines, Spark plug can be installed on two machines (for example, the GE 9FA gas turbines).
What is the difference between spark plugs and igniter plugs?
Ignitors were used on low speed engines and, when properly maintained, work well. Spark plugs use a fixed spark gap and depend on a timed spark from a high voltage transformer (ignition coil) to provide ignition. Both types can be either battery or magneto powered.
What to do when the turbine fails to ignite?
Unless the sequencing/application code in the turbine control panel is non-standard, when the alarm “FAILURE TO IGNITE” is annunciated the turbine will NOT trip, but will just continue to crank. Just select CRANK, wait about 30 seconds, then re-select FIRE or AUTO and the unit will go through a purge and fire sequence.
What are the most common failures of gas turbines?
The testing methods are designed to detect some of the most common failure modes for gas turbines, including corrosion, cracking, fatigue, weld defects, and leaks, allowing businesses to make crucial asset management decisions with a view of optimizing maintenance resources. Some of the common NDT/NDE techniques include:
What is included in the inspection of a turbine?
The inspection generally includes that of the combustion chamber outlet ducts, covers and turbine fuel nozzle for blockages, cracks, pits and corrosion in addition to the inspection of the first stage turbine blades and nozzle guide vanes for warping, cracks, or foreign object damage.
What happens when a gas turbine goes down?
When a gas turbine goes down, recovery can be an expensive, time-consuming process. Knowing what can go wrong and how to anticipate turbine failures can help you avoid a difficult unplanned outage. Gas-fired power is hot and getting hotter.