Replacement Parts

TECHNICAL DATA
189
|
HYDRONIC SOLUTIONS CATALOG
formulas
 P=
HD
144
H=
D
144 P
Where:
p = Pressure change corresponding to the head added or lost (psi)
h = Head added or lost from the liquid (feet of head)
d = Density of the liquid at its current temperature (1lb/ft
3
)
the flow coefficient c
v
The c
v
is defined as the flow rate of 60°f water that will create a
pressure drop of 1.0 psi through the valve.
Where:
p = pressure drop across the device (psi)
D = density of the fluid at its operating temperature (1lb/ft
3
)
62.4 = density of water at 60°f (lb/ft
3
)
f = flow rate of fluid through the device (gpm)
c
v
= Known c
v
rating of the device (gpm)
∆P =
To solve for Hydraulic Resistance, R:
or
See R-Series and R-Parallel for
Head Loss (due to Friction) H
L
(ft)
or =
Where P is the pressure dierence in psi
Total head loss, H
T
(ft):
H
T
= Friction head + static head + discharge head*
*note: For closed loop systems, static head and discharge head = 0
C value C =
Alpha value, α:
See alpha value chart
Equivalent pipe length, L:
Flow, f (gpm):
or
where Q = actual btu/hr delivered to water (ibr)
T = temperature dierence on °f
operating cost
H=
where:
E = annual operating cost of the piping system ($/yr)
D = density of the fluid at its typical operating
temperature (lb/ft
3
)
H = head loss across a device due to viscous friction
(ft of head)
f = flow rate associated with the above head loss (gpm)
T = number of hours per year during which the
circulator operates (hr/yr)
K = cost of electrical energy ($/kwh)
p = eciency of the motor/pump assembly (decimal
percent)
pressure ratings vs. operating temperatures
solder
service
temp.
in °f
max. allowable
water pressure
for (¼" to 1"
tube sizes) in psi
max. allowable
water pressure
for (1¼" to 2"
tube sizes) in psi
50/50
Tin/Lead
100 200 175
150 150 125
200 100 90
250 85 75
95/5
Tin/Anti-
mony
10 0 500 400
150 400 350
2 0 0 300 250
2 5 0 200 175
62.4
D
v
C
f
2
p
L
η
)(f)(T)(k))(D)(H(
-6
3x10
useful formulas for application of system curves
1.75
f
H
R
L
=
CLR α =
1.75
RfH
L
=
1H
L
D
P144 ∆
αL
R
M
R
α =
.25-
c
R
L
α
=
R
H
L
1.75
f=
T500
Q
=f
∆