Flashcards in Valves And Taps Deck (24)
Define a valve or a tap?
Valves and taps are devices designed to regulate, open or close the flow of a liquid or gas in a pipeline
What should valves and taps be made from?
They should be made from brass, or other corrosion resisting alloys
What is a stop valve used for?
Stop valves are used to shut off the flow of a fluid on high pressure water mains
What is a gate valve used for?
Gate valves are used to control the flow of fluids in low pressure systems
Explain what a piller tap is?
Pillar taps are made with long threads which allow them too be fitted through sanitary appliances
Where would a bib tap be used?
They are used for outside use and cleaners sinks
We're should drain valves be fitted?
They are fitted at low points in plumbing and central heating systems
Why have stop valves an arrow printed on them?
To indicate the direction of the water flow
Where would you find a gate valve fitted??
You would find a gate valve fitted on pipework from storage cisterns or central heating systems
What is an air gap and were would you find one?
An air gap is a gap to prevent back siphonage and you would find one on pillar taps
Explain the term cracking a tap?
When the head is loosened and immediately tightened
Explain the purpose of a reseating tool?
It is to re grind the seating in a basin or bath tap if a piece of stone was to damage it's seating
We're are plug valves used?
Plug valves are used on gas lines or sometimes as drain points on water systems
Name the two valves either side of the radiator?
The lock shield valve and the wheelhead valve and thermostatic valves
List two purposes of a lockshield radiator valve?
when balancing a system it ensures a equal distribution of hot water
To shut off to the flow to the radiator
List 2 purposes of a wheelhead radiator valve?
It is used too turn the heater on and off.
Lost two valves suitable for use on low pressure water systems?
Gate valves and lever valves
List one advantage and one disadvantage of a gate valve?
they are used to control the flow of fluids in low pressure systems
there is no washers and therefore there is no restriction to the flow of liquids through them
List one advantage and one disadvantage of a stop valve?
they are designed with a rubber tap washer which gives a positive shut off under high pressure
they are slow closing which allows the water flow too slow down when shutting preventing water hammer
List one advantage and one disadvantage of a lever valve?
it is favoured on gas lines
can be used as an alternative to a gate valve on low pressure water systems
List two places that a gate valve is used?
Storage cisterns and central heating systems
List two places that a stop valve is used?
High pressure water mains and were water hammer could occur
List two places that a pillar tap is used?
On a wash basin and in a kitchen sink