sample slides of the 2-day seminar for engineers
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SAMPLE SLIDES OF THE 2-DAY SEMINAR FOR ENGINEERS
As you will notice there are few words on these slides, your trainer will provide you with his experience which will make these images
come alive providing you with the opportunity to reflect and ask questions, the more the
better.
All of the presentation slides are available in a binder supplied with the seminar.
PUMP
SYSTEM ANALYSIS
A BRIEF HISTORY OF PUMPS
A BRIEF HISTORY
France 1600’S
HYDROSTATIC PRESSURE VS. FLUID COLUMN HEIGHT
The weight of a fluid column is:AzVAzVgVF since
Pressure (p) is equal to the weight of the fluid (F) divided by the surface area (A) at the bottom of the fluid column:
zA
zA
A
Fp
PRESSURE VS. THE SHAPE OF CONTAINERS
OPEN SYSTEMS AND ENTHALPY
Conservation of energy demands that:
EPEKEWQE
)()(2
1)()(21
22
21
212121 zzvvg
pppppPEQF
The specific energy or head balance is
)()(2
11122
21
222121 HzHzvv
gHHH EQFP
The energy balance is:
Subsituting other expressions for head terms:
PUMP TOTAL HEAD
THE CONTROL VOLUME APPLIED TO A REAL SYSTEM
PRESSURE HEAD ANYWHERE ON THE SUCTION SIDE OF THE PUMP
H H Hg
v v z H zX F X EQ X X X ( ) ( ) ( ) 1 1 12 2
1 1
1
2
))(()(21)( 1122
21
222121 HzHzvv
gHHH EQFP
0
What is vapor pressure ?
DEFINITION: NPSH is the head at the pump suction minus the vapor pressure head
NET POSITIVE SUCTION HEAD AVAILABLE (N.P.S.H.)
N.P.S.H. REQUIRED
HOW IS THE N.P.S.H. REQUIRED LEVEL DETERMINED?
SPECIFIC SPEED
Example
126697
5001750
)(
)()(75.075.0
x
fluidftH
USgpmQrpmNNS
NPSH REQUIRED CURVES
OPTIMAL SELECTION OF THE IMPELLER DIAMETER AND PUMP
TSvEQFP HqHqHqHqH )()()()(
SYSTEM CURVE
Why increase the impeller diameter when the flow must be increased?
MEASURING TOTAL HEAD
SDP EEH
GDD
GDD zg
vHE 2
2
GSS
GSS zg
vHE 2
2
)()(21 22
GSGSGDGDSDP HzHzvvg
H
SG
psigpfluidftHand
SG
psigpfluidftH GS
GSGD
GD
31.2)()(
31.2)()(
SG
psippzzvv
gfluidftH GSGD
GSGDSDP
31.2))(()()(
2
1)( 22
SOURCES OF INFORMATION ON MOTOR EFFICIENCIES
DATA BASE - MotoMasterDepartment of Energy USA (DOE)
1. Replace a standard motor with a high efficiency motor
Replace a standard efficiency motor with one that meets or surpasses the NEMA Premium standard
Typically 1.5 to 5% and as much as 8%
When the motors are defective or at the end of their useful life or when a motor must be replaced to accommodate a VFD.
Opportunities in electrical energy reduction
Possible decrease in electrical
consumption 1
Winning conditions
Opportunities with higher return
High efficiency motors
2. Install a variable frequency drive (VFD)
A VFD can adjust the speed of a motor in response to a variable demand avoiding the throttling of control valves or the opening of recirculation control valves and the energy losses incurred.
Typically 12 to 15% and as
much as 27%
Ideal solution when the flow
varies between 40 and 60%
Opportunities in electrical energy reduction
Possible decrease in electrical
consumption 1
Winning conditions
Opportunities with higher return
66
PUMP
SYSTEMS
Pumps in parallel - Instability
Minimum submergence of the pump inlet
The effect of air (or gas) entrainment in the pump suction
VARIOUS ITEMS
Quick guide
Viscosity
ASME max. pressure allowable
DYNAMIC VISCOSITY
dydvKF dy
dv
KAdy
dvAK 1
dydv
1
THE EFFECT OF VISCOSITY ON PUMP PERFORMANCE
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