Ch. 5 Flashcards
- Lube oil systems provide two basic functions.
a. Filtration and antifriction.
b. Lubricating sliding surfaces in the bearings and cool the bearings.
c. An adequate supply of oil to machinery and cooling machine parts.
d. Filtration and lubricate sliding surfaces.
e. Vibration dampening and cooling the bearings.
b. Lubricating sliding surfaces in the bearings and cool the bearings.
- All major oil systems consist of what basic components?
1) An oil reservoir to ensure an adequate supply of oil 2) Filters to ensure the oil is clean 3) Pumps to provide pressure 4) Coolers to ensure oil temperatures are kept within operating limits 5) Protective, monitoring and control devices
a. 1, 2, 3, 4
b. 1, 2, 5
c. 1, 2, 3, 4, 5
d. 1, 5
e. 5
c. 1, 2, 3, 4, 5
1) An oil reservoir to ensure an adequate supply of oil
2) Filters to ensure the oil is clean
3) Pumps to provide pressure
4) Coolers to ensure oil temperatures are kept within operating limits
5) Protective, monitoring and control devices
- Gas turbines use what two different types of bearings?
1) Antifriction (roller and/or ball) bearings 2) Radial (journal or tilt-pad) bearings 3) Axial (spherical) bearings 4) Take-up (frame) bearings 5) Swing (levered) bearings
a. 1, 4
b. 1, 2
c. 1, 3
d. 2, 4
e. 4, 5
b. 1, 2
1) Antifriction (roller and/or ball) bearings
2) Radial (journal or tilt-pad) bearings
- Why is natural gas the best fuel for a gas turbines?
a. It promotes the most efficient combustion and produces the lowest environmental emissions.
b. It is less expensive than other fuel sources.
c. It has the highest efficiency of combustion.
d. It has less contaminants as compared to other fuels sources.
e. It is a lower explosion risk than other fuels.
a. It promotes the most efficient combustion and produces the lowest environmental emissions.
- Routine maintenance on a gas turbine should involve checking for fuel leaks on a __________ basis.
a. yearly
b. monthly
c. weekly
d. daily
e. hourly
d. daily
- An essential auxiliary in a gas turbine installation is:
a. A generator
b. A reheater
c. A starting motor
d. An air heater
e. A water pump
c. A starting motor
- Introducing warm air into the gas turbine intake as a result of an anti-icing system will?
a. Reduce the capacity of the unit, because warm air is less dense than cold air.
b. Form ice in the air intake.
c. Cause major damage resulting in catastrophic destruction of the compressor section blading.
d. Bleed air from the compressor.
e. Increase hot turbine exhaust.
a. Reduce the capacity of the unit, because warm air is less dense than cold air.
- What is the final step in the sequence of starting a Gas Turbine?
a. Preparation for startup
b. Loading
c. Warmup
d. Crank and lightoff
e. Start initiation
b. Loading
- What is the first step in the normal shutdown of a gas turbine?
a. Reduce the speed to idle so the gas turbine can cool down.
b. Open the breaker that connects the generator to the power system.
c. Close the fuel valve.
d. Stop the rotor.
e. Stop the lube oil system.
a. Reduce the speed to idle so the gas turbine can cool down.
- In order to keep the gas pass of a gas turbine clean the following must be done:
1) Inspect and clean air intake filters 2) Water washing of compressor blades 3) Inspect and clean air intake ducts 4) Good quality fuel must be used
a. 1, 2
b. 1, 3
c. 1, 2, 3
d. 1, 2, 3, 4
e. 1, 3, 4
d. 1, 2, 3, 4
1) Inspect and clean air intake filters
2) Water washing of compressor blades
3) Inspect and clean air intake ducts
4) Good quality fuel must be used
- Why do microturbines require only air bearings:
1) No governing oil system 2) Small overall size 3) Simplicity of components 4) Everything on one shaft 5) No oil systems
a. 1, 2
b. 2, 3
c. 2, 5
d. 3, 4
e. 4, 5
c. 2, 5
2) Small overall size
5) No oil systems
- Most aero derivative turbines lube oil systems require?
a. Two back lube oil pumps
b. Separate inlet and outlet filter systems
c. Separate lube oil tanks and coolers
d. Separate lube oil systems
e. Separate back up pumps
d. Separate lube oil systems
- Thrust bearings on dual shaft gas turbines are positioned:
a. At the front of the compressor and next to the turbine bearing.
b. At the front of both the compressor and the turbine section.
c. At the back of both the compressor section and the turbine section.
d. At the back of the compressor and next to the turbine bearing.
e. At the front and back of the turbine section.
a. At the front of the compressor and next to the turbine bearing.
- Tilt pad bearings are used:
1) In aero-derivative gas turbines 2) According to the manufacturers specifications 3) On duel shaft industrial gas turbines 4) In large industrial gas turbines 5) With pivot pins
a. 1, 2
b. 2, 3
c. 3, 4
d. 4, 5
e. 5, 1
d. 4, 5
4) In large industrial gas turbines
5) With pivot pins
- Aero-derivative lube oil systems use a scavenge pump to:
a. Recycle oil form the cleaning system
b. Collects oil from all users for recycling
c. Siphons off small amounts of oil for cleaning
d. Collects oil from the supply and return filters for cleaning
e. Returns the oil from the bearings to the supply
e. Returns the oil from the bearings to the supply
- Natural gas is the best fuel for gas turbines because:
1) No onsite storage 2) Most efficient combustion 3) Simplest control system 4) Highest heat value 5) Cleanest burning
a. 1, 3
b. 2, 4
c. 3, 5
d. 2, 5
e. 2, 3
d. 2, 5
2) Most efficient combustion
5) Cleanest burning
- A fuel gas compressor must be used on gas turbines if?
a. The complexity of the gas system reduces the gas pressure to low
b. The gas supply pressure is less than the compressor last stage pressure
c. The total pressure drop across the combustors is too great
d. Multiple gas nozzles drops the burner gas pressure too low
e. The combustor outlet pressure is greater the compressor outlet pressure
b. The gas supply pressure is less than the compressor last stage pressure
- The most important component of a fuel metering system is?
a. Fuel gas Hi/Lo pressure switches
b. Duplex filters/separators
c. Fuel metering valve
d. Primary and secondary shut off valves
e. Fuel gas scrubber
c. Fuel metering valve
- The use of a low heating value (LHV) fuel requires:
a. Special nozzles and combustors
b. Higher pressure gas supply
c. Higher pressure gas compressors
d. Higher pressures from the compressor
e. Larger bore piping for high flow rates
a. Special nozzles and combustors
- Typical fuel gas metering valves are:
a. Pneumatically actuated
b. A type of pneumatic gas metering control valve
c. Hydraulically actuated
d. Electro-pneumatically actuated
e. Becoming electrically actuated
e. Becoming electrically actuated
- Gas Turbines use duel fuels for:
1) Consistent power delivery 2) Use as backup 3) Increasing overall power output 4) Switching to cheaper fuels 5) Less complicated controls during operation
a. 1, 2
b. 2, 3
c. 2, 4
d. 3, 4
e. 4, 5
c. 2, 4
2) Use as backup
4) Switching to cheaper fuels
- Fuel system daily maintenance checks consist of:
1) Checking the treatment components 2) Checking for fuel leaks 3) Checking fuel pressures and temperatures 4) Checking Delta P across the filters 5) Checking the protective devices
a. 1, 2
b. 2, 3
c. 3, 4
d. 2, 4
e. 3, 5
b. 2, 3
2) Checking for fuel leaks
3) Checking fuel pressures and temperatures
- The most important requirement in a Duel fuel system is:
a. Two types of fuels
b. Ability to burn both fuels together
c. A complex control system
d. Proper design of the combustors
e. Special fuel nozzles
e. Special fuel nozzles
- Fuel treatment systems consist of :
a. Centrifuges, filters , strainers , pumps and related instrumentation
b. Filters, dewatering and chemical treatment
c. Centrifuges, filters, dewatering and chemical treatment
d. Dewatering and chemical treatment
e. Mechanical and chemical treatment
c. Centrifuges, filters, dewatering and chemical treatment
