An essential auxillary in a gas turbine system is
regenerator
starting motor
intercooler
waste heat boiler
combustor
A gas turbine is started in the following sequence of operation 1. air is heated in the combustor 2. air is drawn into the compressor 3. exhaust gases expand through the turbine 4. air is exhausted to atmosphere or hrsg
1,2,3,4
2,1,3,4
4,2,3,1
2,4,1,3
3,1,2,4
Air choking in the high pressure end of the compressor is also termed:
sputtering
back-firing
choking
surging
dead-heading
When starting a gas turbine in manual mode, what would be the first step
start the starting motor
engage the ignitors
load the power turbine
engage the turning gear
start the auxillary systems
Water washing and adding chemicals to fuels that contain sodium or vanadium is primarily for
reducing deposits on turbine blades
reduce blade erosion
lower exhaust gas temperatures
reduce turbine blade erosion
lower NOX emmisions
Major overhauls are performed on a gas turbine:
annualy
when performance is poor
monthly
according to the manufacturers specifications
during off-peak hours
Which of the following components will reduce noise pollution from a gas turbine system: 1. inlet silencers 2. exhaust silencers 3. acoustic insulation 3. using axial air compressors
1,2
2,3,4
1,2,4
1,2,3
Which interlocks need to be in the start position to start a gas turbine 1. oil pressure normal 2. dampers and ducting open 3. controls circuits energized 4. governer in start position
Minor servicing carried out on a gas turbine:
is done monthly
is done annualy
may only allow some adjusting to the combustor unit
will include power turbine blade replacement
will include compressor balancing and mechanical maintenance
when inspecting the flame tube of a gas turbine during a turnaround the operator should check for
distortion
proper ignition
air flow restrictions
scaling
corrosion salts
combustion unit inspections and maintenance includes 1. cleaning 2. ignition checks 3. adjusting fuel flows 4. igniters and retraction gear tested
The lubrication system on a gas turbine for be checked for: 1. leaks 2. water 3. dirt 4. metal particles