This document provides an overview of pumps, valves, and fans used to move fluids. It defines the basic components and types of valves including stop valves like globe and gate valves, check valves, and special valves. Pumps are defined as devices that use an external power source to move fluids, overcoming friction and pressure differences. The basic laws of pumps are described, including Bernoulli's theorem. The main types of pumps - positive displacement and non-positive displacement like centrifugal - are outlined. Pump characteristics like flow, head, power, and speed are also covered. Finally, the document briefly discusses fans and their similarities to non-positive displacement pumps.

1. PUMPS, VALVES,
& FANS
…Moving fluids

2. Objectives
• Comprehend the basic construction
and application of valves used
• Comprehend the basic operation and
application of different pumps
• Know Bernoulli’s principle, the
concept of pressure, & Net Positive
Suction Head
• Be familiar with operation and
application of centrifugal & axial fans

3. Valves
• Def’n: devices which control the amount
and direction of fluid flow in piping
systems
• Typically made of bronze, brass, iron, or
steel alloy
• Components:
- Valve body - Packing
- Disc - Packing gland/nut
- Seat - Stem
- Bonnet - Wheel

4. Types of Valves
• Two basic groups:
• Stop valves - used to shut off or partially
shut off the flow of fluid ( ex: globe, gate,
plug, needle, butterfly)
• Check Valves - used to permit flow in only
one direction (ex: ball-check, swing-check,
lift-check)
• Special types:
• Relief valves
• Pressure-reducing valves
• Remote-operated valves

5. Stop Valves
• Globe Valves
• Most common type of stop valve
• Used in steam, air, water, & oil lines
• Disc attached to valve stem rests
against seat to shut off flow of fluid
• Adv: Used for throttling
• Disadv: flow resistance

6. Globe Valve

7. Stop Valves
• Gate Valves
• Used when there must be straight-line
flow of fluid w/ min. resistance
• Gate usually wedge-shaped or a vertical
disc
• Adv: No flow restrictions
• Disadv: poor throttling

8. Gate Valve

9. Stop Valves
• Butterfly Valves
• Used in water, fuel, and ventilation
systems
• Adv: small, light-weight, & quick-acting
• Disadv: leaks early & only low-flow
throttle
• Ball Valves
• Similar to butterfly valves
• Normally found in seawater, sanitary,
trim and drain, and hydraulic systems

10. Butterfly Valve

11. Check Valves
• Controls direction of flow
• Operated by flow of fluid in pipe
• Types:
• Swing check - disc moves through an
arc
• Lift check - disc moves up and down
• Ball check - ball is located at end of
stem and lifts to allow flow

12. Swing-check Valve

13. Relief Valves
• Used to protect piping system from
excessive pressure
• Opens automatically when fluid
pressure becomes too high
(pressure acts against spring
pressure)
• Relieving pressure set by an
adjusting screw

14. Pressure-reducing Valves
• Used to automatically provide a
steady, lower pressure to a system
from a higher pressure source
• Used in air, lube-oil, seawater, and
other systems

15. Remote-operated Valves
• Valves that allow operation from
distant stations
• Types:
• Mechanical - uses reach rods and gears
• Hydraulic - uses fluid and piston set up
• Motor - uses and electric or pneumatic
motor
• Solenoid - uses coil and core
mechanism to open or close on an
electric signal

16. Pumps

17. Pumps
• Def’n: device that uses and external
power source to apply force to a fluid
in order to move it from one place to
another
• Must overcome:
• (1) frictional forces from large quantities
of fluid
• (2) difference in static pressure between
two locations
• Must provide any velocity desired

18. Pumps – Bernoulli’s
Theorem
• Pressure head: measure of fluid’s mech. PE
• Velocity head: measure of fluid’s mech. KE
• Friction head: measure of energy lost that heats
fluid
Z1 + P1/r + V1
2/2g = Z2 + P2/r + V2
2/2g + [(U2 – U1) – W – Q]
q + wshaft = (h2 – h1) + (v2
2 – v1
2)/2 + g(z2 –z1)
Z/z: fluid height; P: fluid pressure; r: fluid density
V/v: fluid velocity U: internal energy W/w: work
Q/q: heat transferred h: enthalpy g: grav.
acceleration
• BOTTOM LINE: Total energy within the control volume is

19. Components of Pumps
• Drive mechanism (steam, electric,
gear)
• Pump shaft
• Impeller or piston
• Casing

20. Types of Pumps
• Positive Displacement
• Fixed volume of fluid is displaced
during each cycle regardless of static
head/pressure pumping against
• Uses either a piston, gear, or screw type
(reciprocating, rotary gear, rotary screw,
etc)

21. Positive Displacement
Pump

22. Pumps
• Non-positive Displacement: volume
of fluid is dependent on static
head/pressure
• Centrifugal: impeller inside a case
(called volute). Impeller is a disc w/
curved vanes mounted radially (like a
paddle wheel)
• Suction is the Eye -> fluid accelerated as it
travels outward & then enters volute
• Propeller: uses prop inside casing to
move fluid -> not used much in Navy

23. Centrifugal Pump

24. Pumps
• Jet pumps:
• Bernoulli’s principle and no moving
parts
• Velocity Head vs. Pressure head
hin + vin
2/2 = hout + vout
2/2

25. Jet Pump
• Types:
• Eductor - used to pump liquids
• Ejector - used to pump gases

26. Pump Characteristic Curves
• Pump Parameters:
• N = pump speed, RPM
• V = volumetric flow rate, GPM
• Hp = pump head (discharge pressure),
psig
• P = power required, Hp
• Centrifugal Pump Laws
• V a N
• Hp a N2
• W a N3

27. Positive Displacement
Pumps
Hp
GPM
N1 N2
N2 = ____

28. Centrifugal Pumps
• Parallel Pumps
Hp
GPM
2 Pumps
1 Pump
V2 = ____
Hp2 = ____

29. Centrifugal Pumps
• Series pumps (called staging)
Hp
GPM
V2 = ____
Hp2 = ____
2 Pumps
1 Pump

30. Fans
• Same Principle as Non-positive
displacement pumps
• Types:
• Centrifugal: majority used for
compressors
• Axial (like propeller): cooling fans

31. Fans

32. Questions?
Questions?