Basic Systems Flashcards
What is the definition of a system?
A series of INTERCONNECTING PIPES and components to deliver a substance fro one point to another
What is an open loop system?
When the fluid is consumed
What is a closed loop system?
Working fluid is re used
Example of an open loop system
Fuel system
Example of a closed loop system
Fresh water cooling system
What is a fuel system?
Fuel is taken from storage
And delivered in a clean water free condition
To injectors of the diesel engine
Name the 3 types of tanks
Header, service, drain
What is a header tank?
Reservoir to top up tank or system
What is a service tank?
Reservoir of water free fuel
What is a drain tank?
Collects oil from a system
What is a tank gauge for?
Used for measuring fuel in a tank
Name the 3 types of tank gauge
Contents
Sounding
Gauge Glass
What is a contents gauge for?
Hom much liquid
What does the sounding gauge measure?
Depth measured with dip tape and conversion chart
What does gauge glass measure?
How much is left in a tank
Press the button to open the valve and get a correct reading
Explain the process of dipping a tank
- Dip tape is lowered through a sounding tube
- The tape will indicate the depth
- Shown in height and inches
- Convert the measurement into litres / tonnes with a conversion chart
What are strainers for?
Removing large coarse particles
What does the type of pipework depend on?
- The service it provides
- Temperature
- Other materials being used
Name the types of pipework
Phosphor Bronze
Copper
Copper Nickel
Brass
Plastic
What is phosphor bronze used for?
HPSW
What is Copper pipework used for?
FW systems
What is Copper nickel pipework used for?
Lub Oil
What is brass pipework used for?
Castings
What is plastic pipework used for?
Sewage, and Pre Wet
What do the type of seals depend on?
- Pressure
- Fluid
- Temperature
Name the types of seal
Gaskets
Mechanical
Keelering Couplings
Gland Packing
What are gaskets made from?
Paper , Rubber
What do valve’s do?
Control the flow of liquid or gas to isolate various systems
What is a globe valve?
2 way flow, non return, non return and lift
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What do gate valves do?
Large bore systems (Vent Trunking)
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What do flap valves do?
Non return
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What do Saunders valves do?
Rubber diaphragm
Used in water and fuel system
What do ball seated cockspur do?
90’ turn
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What do pressure relief valves do?
Kept closed by spring pressure, is pressure exceeds, valves are forced open
Prevents overpressurisation
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What do pressure reducing valves do?
Allows fluid and gas to expand reducing its pressure
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What do non return valves do?
Allow substances to pass through, but prevents flow in the opposite direction
What do pumps do?
Moves liquid at pressure through many metres of pipework
Name the different types of pimp
Centrifugal
+ve displacement
Axial
Hand
What do positive displacement pumps do?
Physically moves fluid
As the fluid moves, pressure increases
Reciprocating and Rotary
What do dynamic displacement pumps do?
Moves fluid with energy from an impeller
As fluid slows down, energy state changes
Change of state is due to Bernoullis Theorem
Bernoullis Theorem
As speed increases, pressure decreases
What does a motor do?
Converts electrical energy into mechanical motion
In a HPSW system, Motors drive pumps
Name the system indicators
Vacuum Gauge
Tachometer
Thermometer
Flow meter
Voltage meter
How can a gauge be isolated from a system
Gauge cock
Relationship of bourdon tube and pressure
As bourdon tube Extends, pressure increases
What does a manometer give a visual representation of?
Pressure
What does a tachometer visually represent?
Speed
What does a thermometer visually represent?
Temperature
3 types of thermometer
Fixed Brass
Pocket / Oblong
Clock / Dial
What is a fixed brass thermometer?
Yellow and black stripes
What does a pocket / oblong thermometer do?
Plug screwed into threaded hole in a system
What is the fluid inside thermometers?
Transmission Fluid
What do voltmeter measure?
Potential Difference
What do filters do?
They remove small fine particles
Explain metallic filters
Made from wire wool
Can be reused
Explain absorbant filters
Made from paper and cloth
Can be replaced
Name the 2 types of filter
Metallic and Absorbant
What do pressure control valves do?
Maintain pressure at a certain level
Opens and closes valve
What is Rod gearing?
Valves can be manually shut from another location
Used in emergencies
What is a pressure relief valve
Prevents Over pressurisation
What does an accumulator do?
Holds potential difference under pressure
Exerts force on incompressible fluids
Smooth pulsations and stores energy
