Mechanical Theory 1 Flashcards
What does “open loop system” mean?
Where the working fluid is consumed. For example domestic fresh water/ drinking water
What does a “closed loop system” mean?
Where the working fluid is reused. For example lub oil system, fresh water cooling system.
Name 3 types of tanks
Header tank - reservoir to top up a system
Service tank - supply of clean, water free fuel
Drain tank - collects oil returning from the system
Name 2 different gauges
Contents gauge - (clock/dial) how much fluid is in a tank
Gauge glass - visual indication to tank level (press the button to read)
What are strainers used for?
Removing larger coarser particles from the fluid
The type of pipe work you use depends on?
The fluid being used
The temperature
The pressure
Other types of materials being used within the system
Different types of pipes
Phosphor bronze - high pressure salt water (HPSW)
Copper - Domestic fresh water
Copper nickel - lub oil
Brass - castings/valves, couplings, junctions, taps
Plastic- sewage/ waste systems and pre-wet
What materials can you use as a gasket (seal)
Non asbestos fibre (NAF)
Paper
Leather
Cork
Copper
Rubber
Name different types of valves
Globe valve Gate valve Flap valve Saunders valve Ball seated cock valve Relief valve Reducing valve Non return valve Pressure control valve ROV- remote operation valve
What does a positive displacement pump do?
Gives less flow, increases pressure. Used in for example gearwheel pump and rotary pump
What does a Dynamic displacement pump do?
It gives out a large flow, and low pressure. For example centrifugal pump and axial pump
Name some System indicators?
Bourdon tube Manometer Tachometer Thermometer - fixed brass/ standard pocket/ clock/dial face Flow meters Voltage meters
What do filters do in a system
Filters remove small fine particles.
Materials used for filters are?
Metallic - wire wool, steel plates and gauze screens. Reusable, can be washed and refitted when blocked
Absorbent - fabrics, felt, yarn, paper. Not reusable
