Types of Valves Used In Water Supply Pipe Lines

Valves in pipe lines are provided to control supply of water. They are used to stop supply when any repair is carried in pipe line. There are fourteen types of valves for plumbing.

Stop Valve
This valve is suitable means of connections for inserting and controlling the flow of water. Nominal size of valve is designated by nominal bore of the pipe to which the valve is normally fitted. The body and bonnet of this valve is made from cast brass.  
In large buildings sufficient numbers of stop valves are fixed on branch pipes to minimize interruption of supply during repairs. A stop valve is also called stopcock. There are two types of stop valves.
1).  Internally threaded 
2).  Externally threaded 

1. Fancy Stop Valve

   These valves are available in normal sizes of 15 mm and 20 mm. These are also called open stopcock valves. 

2. Angle Stop Valve

   This valve has inlet and outlet at right angles to each other. This is used to stop supply of water to geyser, flushing cistern and wash basin etc. This valve is also used for servicing of water fitting to be carried out without shut off complete water supply of the house.

3. Concealed Stop Valve

   It is used to regulate supply of hot and cold water to shower, mixer etc. in concealed plumbing line. 

4. Gate Valve

   Gate valve is full way valve which is inserted into a pipeline for controlling or stopping the flow of water. This valve offers low resistance to the flow of water. The valve is closed by turning hand wheel into clock wise direction. Nominal sizes of valves are 15 mm to 100 mm.  

5. Ball Valve

   Ball valve is an automatic flow control device. Regulating principle is the level of some free water surface.

6. Foot Valve

   This valve is placed at the bottom of suction pipe of pump. This valve lets the water to enter suction pipe when it is opened and prevents the water from flowing back when it is closed.  

7. Air Relief Valve

   This valve is an integral part of a pool of pumping and filtration system. When the pump of pool pumps out water from the pool, the water is forced through a filter. Then the water is forced through air-relief valve.

8. Pressure Relief Valve

   This valve protects pipe from sudden increase in pressure. It is a device attached with a boiler or other vessel for relieving the pressure of steam automatically before it becomes enough to cause burst. 
Scour Valve or Washout Valve
This valve is used at valley point of a pipe line to clean pipe line.
Sluice Valve or Globe Valve
These valves are used to control the flow and for frequent operation. These are normally used in CI main line.
Butterfly Valve
This valve contains a circular disc which rotates in the direction of flow in pipe. It is a type of flow control device that is used to regulate flow of fluid through a section of pipe. This valve is similar to ball valve in operation. A flat circular plate is fixed in the center of pipe.
Float Valve or Ball Cock
This valve is used in water tanks and cisterns to maintain constant water level and to prevent overflow. It is activated by means of a lever and float (ball). The rise and fall of ball controls the flow of water. This valve is generally made for high, medium and low pressure.
Bib cock/bib tap
A Bib cock/Bib tap is fitted horizontally to the pipe as in kitchen, bath etc. This valve is used to obtain water from direct water supply or from storage tank.