2. PIPING SCHEDULE
• NOMINAL PIPE SIZE IS EQUAL TO O.D.
( FOR PIPE SIZE 14 INCH AND LARGER PIPE SIZES ).
ID
2
#
PIPE SCH. 80 ( X STRONG )
ID
1
#
PIPE SCH. 40 ( STD PIPE )
OD
ID
3
#
PIPE SCH. 160 ( XX STRONG )
• PIPES WITH THE SAME NOMINAL PIPE SIZE HAVE THE
SAME O.D BUT DIFFERENT I.D.
• NOMINAL PIPE SIZE IS NOT EQUAL TO
THE OD. OR ID. OF THE PIPE
8. PIPE LINE HYDRAULIC CACULATIONS
B
H total = h + Pipeline head losses + Terminal Head
C
PUMPING STATION
TERMINAL
A
h
9. PRESSURE DROPAFFINITY LAWS
IF THE FLOW RATE CHANGES
FOR SAME PIPE SIZE
P1
Q1
2
P2
Q 2
IF THE PIPE SIZE CHANGES
FOR SAME FLOW RATE
P1
P2
D2
5
D 1
IF THE PIPE SIZE AND
FLOW RATE CHANGE
P1
Q1
2
P2
Q 2
D2
5
D 1
10. R N It is the ratio between fluid inertia force and shear force
R N It is a number expressing the degree of turbidity of fluids
fluid inertia force
R N fluid shear force
Fluids flow
Laminar Critical Turbulent
R N < 2000 R N = 2000 - 4000 RN > 4000
fluid shear force A
d
RN (Dimensionless form )
R N
2 2
=
=
=
=
=
L
L
L
L
fluid inertia force = mass acceleration
= L
3
2 2 2
= L
L
11. 1- LIQUIDS
a- RN < 2000 ƒ = 64 / R N
b- RN > 4000 ƒ depends upon (surface roughness )
Friction factor ƒ
c- Max . Gas Velocity = Sonic Velocity
V S = ( k.g.R.T )
1
2
2- GASES
FOR COMPRESSORS
a- Adiabatic process
P1 V1 P 2 V 2
T 1
T 2
b- Isothermal process (t = constant ) FOR PIPE LINES
ƒ Lv2
ƒ L v 2
2 g D D 2 g
= = K
P =
P P
v 2
2 g
12. El = 100 ft
10 mi of 48 pipe,
e =0.0003 ft
El = 230 ft 2
1
6
Re 1.01x10
4
7.5x10
D
e
0.0185
f
13. 13
Introduction
• Head
• Resistance of the system
• Two types: static and friction
• Static head
• Difference in height between
source and destination
• Independent of flow
Pumping System Characteristics
destination
source
Static
head
Static
head
Flow
14. 14
Introduction
• Static head consists of
• Static suction head (hS): lifting liquid relative to
pump center line
• Static discharge head (hD) vertical distance
between centerline and liquid surface in destination
tank
• Static head at certain pressure
Pumping System Characteristics
Head (in feet) = Pressure (psi) X 2.31
Specific gravity
15. 15
Introduction
• Friction head
• Resistance to flow in pipe and fittings
• Depends on size, pipes, pipe fittings, flow
rate, nature of liquid
• Proportional to square of flow rate
• Closed loop system
only has friction head
(no static head)
Pumping System Characteristics
Friction
head
Flow
16. 16
Introduction
Pump performance curve
• Relationship between head and flow
• Flow increase
• System resistance increases
• Head increases
• Flow decreases to zero
• Zero flow rate: risk of
pump burnout
Pumping System Characteristics
Head
Flow
Performance curve for
centrifugal pump
17. 17
Introduction
Pump operating point
Pumping System Characteristics
• Duty point: rate of
flow at certain
head
• Pump operating
point: intersection
of pump curve and
system curve
Flow
Head
Static
head
Pump performance curve
System
curve
Pump
operating
point
18. Assessment of pumps
• Pump shaft power (Ps) is actual horsepower delivered
to the pump shaft
• Pump output/Hydraulic/Water horsepower (Hp) is the
liquid horsepower delivered by the pump
How to Calculate Pump Performance
Hydraulic power (Hp):
Hp = Q (m3/s) x Total head, hd - hs (m) x ρ (kg/m3) x g (m/s2) / 1000
Pump shaft power (Ps):
Ps = Hydraulic power Hp / pump efficiency ηPump
Pump Efficiency (ηPump):
ηPump = Hydraulic Power / Pump Shaft Power
hd - discharge head hs – suction head,
ρ - density of the fluid g – acceleration due to gravity
19. Assessment of pumps
• Sizing a Pump
• a. Head and Pressure
• Head in feet = Head in Psi X
2.31
• Sp.Gr
• Head in Psi = Head in feet X
Sp. Gr.
• 2.31
• b. Brake Horse Power
• i Centrifugal Terminology
• BHP = Gpm X H (in
feet) X Sp. Gr.
• 3960 X Efficiency
• BHP = Bbl/hr X H (in
feet) X Sp.Gr
• 5657 X
Efficiency
• ii Reciprocating Terminology
• BHP = Gpm X psi
• 1714 X Efficiency
• BHP = Bbl/hr X psi
• 2449 X
Efficiency
Sizing a Pump
In the above expressions,
gpm = US gallons per minute
bph = Barrels per hour
H = Total head in feet of liquid (Differential)
psi = lb per square inch (Differential)
Sp.gr = specific gravity of liquid to be pumped
Motor Wattage
Electrical HP input to Motor = Pump BHP
Efficiency
KW input to Motor = Pump BHP X 0.7457
Motor Efficiency
20. Pumps and Pumping Stations
• Pumps add energy to fluids and therefore are accounted for in
the energy equation
• Energy required by the pump depends on:
– Discharge rate
– Resistance to flow (head that the pump must overcome)
– Pump efficiency (ratio of power entering fluid to power supplied to the
pump)
– Efficiency of the drive (usually an electric motor)
2 2
1 1 2 2
1 2
2 2
pump L
v p v p
z H z H
g g
2
2
L f minor f i
v
H h h h K
g
21. Pump
• (Total) Static head – difference in head between suction and
discharge sides of pump in the absence of flow; equals
difference in elevation of free surfaces of the fluid source and
destination
• Static suction head – head on suction side of pump in absence
of flow, if pressure at that point is >0
• Static discharge head – head on discharge side of pump in
absence of flow
Total static
head
Static suction
head
Static
discharge
head
22. Pump
• (Total) Static head – difference in head between suction and
discharge sides of pump in the absence of flow; equals
difference in elevation of free surfaces of the fluid source and
destination
• Static suction lift – negative head on suction side of pump in
absence of flow, if pressure at that point is <0
• Static discharge head – head on discharge side of pump in
absence of flow
Total static
head Static suction lift
Static
discharge
head
23. Pump
Total static head
(both) Static suction lift
Static
discharge
head
Static suction
head
Static
discharge
head
Static suction head
Static suction lif
Static discharge head
Static d t
Total static h
ischarge he d
ead
a
Note: Suction and discharge head/lift measured from pump centerline
24. Pump
• (Total) Dynamic head, dynamic suction head or lift, and dynamic discharge
head – same as corresponding static heads, but for a given pumping
scenario; includes frictional and minor headlosses
Total
dynamic head
Dynamic
suction lift
Dynamic
discharge
head
Energy Line
25. Example. Determine the static head, total dynamic head (TDH), and total
headloss in the system shown below.
Total static head 730 ft 630 ft 100 ft
pd =48 psig
ps =6 psig
El = 630 ft
El = 640 ft
El = 730 ft
2.31 ft
TDH 48 6 psi 124.7 ft
psi
TDH Static head 124.7 100 ft 24.7 ft
L
H
26. Pump Power
• P = Power supplied to the pump from the shaft; also called ‘brake
power’ (kW or hp)
• Q = Flow (m3/s or ft3/s)
• TDH = Total dynamic head
• = Specific wt. of fluid (9800 N/m3 or 62.4 lb/ft3 at 20oC)
• CF = conversion factor: 1000 W/kW for SI, 550 (ft-lb/s)/hp for US
• Ep = pump efficiency, dimensionless; accounts only for pump,
not the drive unit (electric motor)
TDH
CF p
Q
P
E
Useful conversion: 0.746 kW/hp
