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