This document summarizes a seminar presentation on valve arrangements for a tractor power unit course. It defines a valve as a device that regulates fluid flow, and lists common valve types like sluice valves, reflux valves, pressure relief valves, and air valves. It then describes the functions and working of reflux valves and pressure relief valves. The document includes diagrams of valve components and piping connections like female threaded elbows and crosses.

1. SENTHUR POLYTECHNIC COLLEGE
DEPARTMENT OF AGRICULTURAL TECHNOLOGY
4023510 / TRACTOR AND ITS POWER UNITS
SEMINAR PRESENTATION
Submitted by
S E M I N A R T O P I C
V A L V E S A R A N G E M E N T S
S U B M I T T E D B Y
K A V I Y A
( 2 2 2 1 9 9 7 3 )

2. 9.1 Valves
 A valve is a device that regulates, directs or controls the flow of a fluid by
opening, closing, or partially obstructing various passageways.
Valves are of different types, having different function.
Valves are either self operated or manual.
Valves have many uses in water supply system.
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Source:enginnering discoveries, wikipedia

3. Functions of Valve
To control and regulate the flow of water.
To prevent the flow in the opposite direction.
To release the excessive pressure build up.
To release and admit the air .
To drain pipeline sections
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4. Source: dhbvalves
Types
Of
Valves
Sluice
Valve
Reflux
Valve
Pressure
Relief
Valve
Air
Valve
Drain
Valve
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5. Source:spiraxsarco
10

6. Working Of Reflux Valve
• It consists of a gun metal disc hinged at its top
edge and fitted tightly against an annular
gunmetal seat under its self weight.
• When water flows, the disc rotates round the
hinge due to pressure of the flowing water
and remains in the horizontal plane allowing the
water to pass through it.
• When flow of water stops, disc automatically
falls down and closed the valve.
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7. Pressure Relief Valves
• A relief valve is designed to open at a specific
pressure to help protect pumps and other
equipment from exceeding stress limits
• When pressure rises above the set limit,
a safety valve can divert liquids, gases or a
liquid-gas mixture to a flare header to help
relieve pressure and normalize.
• Known as Safety valves or Automatic Safety
Valves
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Source:Wikipedia/pressure relief valve

8. Working of Pressure Relief Valves
• It consists of a spring loaded disc which can
be adjusted for any pressure by releasing or
compressing spring.
• The valve is fitted on an opening provided at
the top of the pipeline.
• At desired pressure, disc is held tightly and
valves remains closed
• When the pressure in the pipeline exceeds the desired pressure, the disc is
forced to be lifted up and certain amount of water flows out from the cross
pipe thereby releasing the pressure in the pipeline .
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9. 14
Source: automationforum

10. Female threaded elbow
and male threaded pipe
Female/Male Thread Pipe
Source : ebay
25
solvent welding
[′säl·vənt ‚weld·iŋ] (engineering) A technique for joining plastic pipework in which a mixture of
solvent and cement is applied to the pipe end and to the socket, with the parts then being joined
and allowed to set.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-
Hill Companies, Inc.

11. Cross
• Connects Four sections together
• Has one inlet and 3 outlets or vice versa
Source: Palaydisplay
• If a branch line passes completely through a tee, the fitting becomes a cross.
• Also called 4-way fittings
• They often have solvent welded socket
ends or female threaded ends.
Source: homedepot
26

12. Flow
• Standard flow is 0.15 LPS (9 liters per minute)
• Flow increased for densely populated area
and cut down for few households.
• Minimum flow 0.10 LPS and Maximum flow 0.25 LPS
• If design flow demand exceed 0.25 LPS, double faucet stand post may be
built
Source: Dreamstime
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