April 16, 1998
100a
FOAM CONCENTRATE
CONTROL SYSTEM (CCS)
DESIGN AND
CALCULATIONS
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DESIGN DATA
FOAM CONCENTRATE CONTROL SYSTEM (CCS) DESIGN AND CALCULATIONS
OPERATIONAL DETAIL
EXAMPLE FOR 3% UNIT
Design: .03Ao1 = Ao2
~
and if: P1 = P2
Then: .03Q1 = Q2
Yields: 3% Foam/97% Water
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Form No. 082494
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Ao1 = CC inlet area water
Ao2 = CC inlet area of foam
CC = Concentrate Controller
P = Pressures at inlet CC
Q = Flow Rates
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BS
Before attempting to design a concentrate control system, it is imperative that the designer be familiar with
the basic system operation, and the
effect that certain components and
their placement in the system may
have on the operation of the complete system. This becomes very
important when it may be necessary
to deviate from the schematics (Figures 101, 201, 301, & 401), because
of field conditions, etc., such as having to locate the foam bladder tank
more than a total of 50 equivalent
feet away from the system riser, elevation changes, or other related
modifications.
The basic purpose of the foam/water
proportioning system is to proportion
the proper amount of foam concentrate (usually 3% or 6%) with the
proper amount of water (usually
97% or 94%). This concentrate to
water ratio must be maintained even
at the concentrate controller’s minimum flow, since this is very important for closed head (wet, dry or
pre-action) systems, especially in
the initial stages of a fire, when only
a few heads may open. The concentrate controller is actually a modified venturi device, and as water
flows through it, an area of lower
pressure is created, and this lower
pressure is referred to as the metering pressure drop. The higher the
velocity of water flow through the
venturi, the higher the metering
pressure drop created. Therefore,
the controller becomes an effective
proportioning device, only once a
specific amount of flow passes
through it. The point where the
metering pressure drop created
due to flow across the venturi is
greater than the total friction loss
caused by the type of concentrate
moving to the controller, is the
actual low end flow for that particular controller.
The recommended flow ranges for
each Viking/Arrow controller with
various types of 3M foam, can be
found in the "Recommended Flow
Range" table on page 103 of the
"Tank and Proportioners" section of
the Viking Foam Data Book. These
flow ranges are all based upon using
50 equivalent feet of smooth Schedule 40 steel pipe including all fittings,
valves, etc.,, and having a roughness factor of Hazen & Williams C =
120. The 50 equivalent feet is for
the tank water supply pipe and the
foam concentrate discharge piping.
Again, the 50 equivalent feet would
include all pipe, fittings and valves,
etc. Notice that the ATC and 3 X 3
foams have much higher low end
flows than the AFFF Foams do.
This is because the ATC and 3 X 3
foam concentrates are classified as
thixotropic liquids. (Thixotropic
liquids are for calculation purposes,
defined as fluids which begin flowing
more as a thick, jelly like substance,
but once flowing, become less viscous, or flow more easily, and begin
to act more like water.) Therefore,
thixotropic type concentrates require more energy to begin the proportioning process than the AFFF
concentrates do, resulting in higher
low end flows for each controller
size. AFFF concentrates however,
act in a similar manner as water, so
the friction loss is considered the
same as water.
BASIC DESIGN STEPS FOR CCS
The following steps outlined below,
indicate the basic steps necessary
to design a concentrate control system (CCS), including how to perform
the system hydraulic calculations,
when the bladder tank must be located over 50 equivalent feet away
from the riser.
1. SELECT CONTROL SYSTEM TYPE
a. Wet Pipe System (Figure 101)
b. Deluge System (Figure 201)
c. Pre-Action System (Figure 301)
d. Dry Pipe System (Figure 401)
2. SELECT FOAM CONCENTRATE
FOR HAZARD BEING PROTECTED
a. 3M AFFF Concentrate
1. Hydrocarbon (non-polar) fuels
b. 3M ATC Concentrate
1. Alcohol type (water soluble polar solvent) fuels
2. Hydrocarbon (non-polar) fuels
Replaces pages 100a-e with dates prior
to April 16, 1998. Re-dated pages.
April 16, 1998
100b
R
DESIGN DATA
4. CALCULATE SYSTEM FLOW
REQUIREMENTS
a. Area of Hazard (A) X (*D) Density
= Q (System flow) + any additional
demand such as inside hose stations which are supplied off the
common foam/water system
5. SELECT CONCENTRATE CONTROLLER (PROPORTIONER) SIZE
a. Refer to "D" dimension on page
103 in the Tank and Proportioner
Section of the Foam Data Book.
This is the minimum pipe size for
both the tank water supply and
foam concentrate discharge pipe
sizes
8. POSITION BLADDER TANK
AND PROPORTIONER
a. Keep the bladder tank within 50
total equivalent feet of the water
supply and controller
b. Ideal location of controller is level
with top of bladder tank
c. Always consider future accessibility for maintenance purposes
d. Refer to the General Notes and
Warnings in the Viking Foam Data
Book
e. Locate the controller in the riser so
that there is a length of straight
pipe equal to 4 to 5 pipe diameters
on both the inlet and outlet sides
of the controller, to help eliminate
turbulence which can affect proportioning accuracy
BS
a. See appropriate chart on page 103
in the Tank and Proportioner Section of the Viking Foam Data Book
b. Use the smallest controller which
overlaps the total system demand, since it will provide better
low end flows for closed head systems
c. How many heads must open on a
closed head system before the
proportioner’s low flow range is
reached?
d. What is the Permanent Friction
loss for the selected Controller,
and will the final calculations allow
for this additional loss?
7. SIZE TANK WATER SUPPLY
AND FOAM CONCENTRATE
DISCHARGE PIPE SIZES
6. SELECT THE SIZE AND TYPE
OF FOAM CONCENTRATE
BLADDER TANK
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a. Use the formula as detailed in the
General Notes pages of the Viking
Foam Data Book in the Design
Section: TS = TSD X C% X D +
15% where
TS = Estimated Tank Size
TSD = Total System Demand (estimated) from STEP 4 above
C% = Percentage of Foam Concentrate
D = Duration of foam concentrate
in minutes
b. Horizontal or Vertical tank
1. Check plans or actual jobsite
for tank clearances
a. If vertical, then access from
above is required for servicing
b. If horizontal, then access
from one end is required for
servicing
c. Roof hatch is acceptable for
vertical tank access if adequate vertical space is not
100 PSI Available at base of riser.
Estimated concentrate controller
size = 4", with a 10 minute duration.
Step 1. Select Control System Type
a. Wet
Step 2. Select Foam Concentrate For
Hazard Being Protected
a. 3% 3M AFFF
Step 3. Select Type of Foam Concentrate Control Valve
a. Viking Halar® coated Deluge
Valve
Step 4. Calculate System Flow Requirements
a. For this example, a .3 GPM
density is required over a 3500
sq. ft. area of operation, therefore .3 X 3500 sq.ft. = 1050
gpm minimum system flow
Step 5. Select Concentrate Controller
Size
a. A 4" proportioner has a range
which overlaps the 1050 gpm
system demand. It has a minimum flow of 150 gpm, and a
maximum flow of 1200 gpm.
This would mean that at a 100
sq. ft. head spacing and an end
head density of .3 gpm, or a
minimum end head flow of 30
gpm per sprinkler, 5 sprinklers
would have to operate, before
the minimum flow rate for the 4"
controller would be achieved.
(.3 gpm X 100 sq. ft. = 30 gpm
X 5 heads = 150 gpm). The
permanent friction loss for a 4"
controller with a flow of 1050
gpm, is 9.2 psi, according to
the Permanent Pressure Loss
Table found on page 104 in the
"Tank & Proportioners" section
of the Viking Foam Systems
Engineering and Design Data
Book.
Step 6. Select The Size And Type of
Foam Concentrate Bladder Tank
a. Size bladder tank - total system
demand X percentage X duration X 1.15 or 1050 GPM X 10
minutes X .03 X 1.15 = 362
gallons. (Refer to tank size tables for selection). No 362
gallon tank is available so always select the next larger
size, or a 400 gallon tank.
Step 7. Size Tank Water Supply And
Foam Concentrate Discharge
Pipe Sizes
a. "D" dimension on the concentrate controller chart calls for a
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Viking Halar coated Deluge Valve
Manual ball valve
Hydraulically operated ball valve
Electric motor operated ball valve
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a.
b.
c.
d.
available; Double doors at
one end of horizontal bladder tank, if adequate horizontal space is not available
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3. SELECT TYPE OF FOAM
CONCENTRATE CONTROL VALVE
FOAM CONCENTRATE
CONTROL SYSTEM (CCS)
DESIGN AND
CALCULATIONS
There is no need to hydraulically
calculate a bladder tank system,
when the total equivalent length of
both the tank water supply and foam
concentrate discharge piping and fittings do not exceed 50 equivalent
feet. This is because all testing has
been conducted within the 50
equivalent feet of pipe and fittings,
and the minimum and maximum
concentrate controller flow tables
were established using the same 50
equivalent foot standard.
WHAT HAPPENS WHEN THE 50
EQUIVALENT FOOT STANDARD
MUST BE EXCEEDED?
The following examples should be
used as a reference to estimate the
foam concentrate supply piping and
tank water supply pipe sizing, when
the 50 total equivalent feet mentioned above, must be exceeded because of actual jobsite conditions.
#1- System design .30 over 3500 sq.
ft. 3% AFFF Foam - Wet System.
*For specific applications, see Discharge Devices Section "Approved
Sprinklers for use with 3M Foams" for minimum density requirements.
April 16, 1998
100c
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DESIGN DATA
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a. Wet
Step 2. Select Foam Concentrate For
Hazard Being Protected
a. 3 X 3 3M FC-603F
Step 3. Select Type of Foam Concentrate Control Valve
a. Viking Halar® coated Deluge
Valve
Step 4. Calculate System Flow Requirements
a. For this example, a .3 GPM density is required over a 3500 sq.
ft. area of operation, therefore
.3 X 3500 sq.ft. = 1050 gpm
minimum system flow
Step 5. Select Concentrate Controller Size
a. A 4" proportioner has a range
which overlaps the 1050 gpm
system demand. It has a minimum flow of 375 gpm, and a
maximum flow of 1150 gpm*.
This would mean that at a 100
sq. ft. head spacing and an end
head density of .3 gpm, or a
minimum end head flow of 30
gpm per sprinkler, 12 to 13
sprinklers would have to operate, before the minimum flow
rate for the 4" controller would
be achieved. (.3 gpm X 100 sq.
ft. = 30 gpm X 12 heads = 360+
gpm). The permanent friction
loss for a 4" controller with a
flow of 1050 gpm, is 9.2 psi,
according to the Permanent
Pressure Loss Table found on
page 104 in the "Tank & Proportioners" section of the Viking Foam Systems Engineering and Design Data Book.
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f) Check total friction loss established above (1.1 PSI), against
the minimum flow metering
pressure drop of the 4" concentrate controller. This is accomplished by referring to the metered pressure drop table for
the 4" concentrate controller
selected (see page 104 in the
"Tank and Proportioner" section of the foam data book).
Now plot the 1.1 PSI drop on
the metering pressure drop until it intersects the 4" ratio controller flow line. This plot point
will indicate the minimum flow
which must pass through the
concentrate controller (P1) in
order to have balanced pressures at both the foam concentrate inlet (P2) to the controller,
and through the waterway of
the controller. Drop a line
through the new plot point
straight down the graph to establish the minimum flow to
achieve balanced pressure at
the controller. If this flow is
equal to or less than the minimum flow indicated in the table
found on page 103, then the
pipe sizes may remain unchanged. (in this case, the
minimum balance flow is 140
GPM, or 10 gallons below the
minimum, so no pipe sizing
changes are required).
BS
minimum pipe size
of 1 1/2"
diameter pipe.
Step 8. Position Bladder Tank And
Proportioner
a. The example in Figure 2 requires that the bladder tank
be located more than 50
equivalent feet away from the
proportioner.
b. Calculate foam concentrate flow
through 1 1/2" piping at minimum 4"concentrate controller
flow or 150 GPM (see table on
page 103) 3% of 150 GPM =
4.5 GPM is the minimum flow
required for 4" concentrate
controller to proportion AFFF
properly.
c. Calculate the total friction loss
for the foam concentrate flow
(4.5 GPM) through the tank
water supply and the foam concentrate supply line (95 total
equivalent ft). Friction loss for
4.5 GPM flowing through 1-1/2"
pipe @ C = 120 is .001 PSI/ft
(The friction loss for AFFF
foam concentrates is approximately the same as for
water. For ATC type foam
concentrates, refer to the appropriate flow rate vs. pressure drop table for the type of
ATC foam being used). Total
pressure loss = 95 equivalent
ft x .001 = .10 PSI
d. Add total friction loss (0.10 PSI)
to tank loss (1 PSI) = 1.1 PSI
total friction loss.
e. Check elevation of ratio controller (should be level with top of
tank in most cases). Note: This
example assumes that the concentrate controller is level with
the top of the tank.
FOAM CONCENTRATE
CONTROL SYSTEM (CCS)
DESIGN AND
CALCULATIONS
#2 - Assume the same conditions
as in Example #1, except that the
foam concentrate will beFC-603F 3
X 3, in lieu of AFFF. Therefore, the
system design will still be .3 over
3500 sq. ft. using FC-603F foam wet system. 100 psi will be available
at the base of the riser.
Step 1. Select Control System Type
FIGURE 2
EQUIVALENT LENGTH FOR:
1-1 1/2 Viking E-1 Halar® coated deluge CCV
1 -1 1/2 " swing check valve
3 -1 1/2 90° elbows in tank water supply (3 ea @ 4 ft)
3 -1 1/2 90° elbows in concentrate line (3 ea @ 4 ft)
1 -Concentrate line pipe length (sch 40, c=120)
1 -Tank water supply length (sch 40; c=120)
1 -Full port ball valve (tank water supply)
1 -full port ball valve(foam concentrate supply)
=
=
=
=
=
=
=
=
Total equivalent feet of 1 1/2 pipe
= 95 ft.
10 ft.
9 ft.
12 ft.
12 ft.
25 ft.
25 ft.
1 ft.
1 ft.
*NOTE: The minimum system flow
above is 1050 gpm, and the
maximum flow of the 4" proportioner, when using ATC foam
concentrate, is 1150 gpm. This
may require a change to a 6"
proportioner, when final system
calculations are completed, as
actual final calculations usually
have a 5% to 10% system overage, due to system configuration, pipe sizes, sprinkler K factors, and other related reasons.
A 10% overage on this system
would exceed the 4" controller’s
maximum flow range.
NEVER ALLOW THE SPRINKLER SYSTEM’S TOTAL
FOAM/WATER DEMAND TO
EXCEED THE CONTROLLER’S
MAXIMUM
FLOW
RANGE.
April 16, 1998
100d
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DESIGN DATA
plished by referring to the metered pressure drop table for
the 4" concentrate controller
selected (see page 104 in the
"Tank and Proportioner" section of the foam data book).
Now plot the 15.16 PSI drop on
the metering pressure drop until it intersects the 4" ratio controller flow line. This plot point
will indicate the minimum flow
which must pass through the
concentrate controller in order
to have balanced pressures at
both the foam concentrate inlet
to the controller, and through
the waterway of the controller.
Drop a line through the new plot
point straight down the graph to
establish the minimum flow to
achieve balanced pressure at
the controller. If this flow is
equal to or less than the minimum flow indicated in the table
found on page 103, then the
pipe sizes may remain unchanged. (in this case, the
minimum balance flow is 530+
GPM, which is higher than the
minimum flow we are looking
for, so the pipe sizing must be
increased to reduce the friction
loss). We need to reduce the
total loss to about 7.5 psi, in
order to reach the minimum
range of the 4" proportioner.
Therefore, recalculate the pipe
sizing in the foam concentrate
line as shown in Figure 4 on
page 100e.
b. Calculate foam concentrate flow
through 3" concentrate piping
at minimum 4" concentrate
controller flow of 375 GPM (see
table on page 103) 3% of 375
GPM = 11.3 GPM is the minimum concentrate flow required
for 4" concentrate controller to
proportion ATC properly. This
is also the amount of water
which will flow through the tank
water supply piping to displace
the foam concentrate flowing
into the concentrate controller.
c) Calculate the total friction loss
for the foam concentrate flow
(11.3 GPM) through the tank
water supply and the foam concentrate supply line. Friction
loss for 11.3 GPM flowing
through 3" pipe @ C = 120 is
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c. Calculate the total friction loss
for the foam concentrate flow
(11.3 GPM) through the tank
water supply and the foam concentrate supply line (103 total
equivalent ft). Friction loss for
11.3 GPM flowing through 11/2" pipe @ C = 120 is .245
PSI/ft (The friction loss for
ATC foam concentrates is
very different from AFFF.
For ATC type foam concentrates, refer to the appropriate flow rate vs. pressure
drop table in the Foam Concentrate Section of the Foam
Data Book for the type of
ATC foam being used).
Total pressure loss
for 57 equivalent
ft x .245
= 13.97 PSI
Total pressure loss
for 38 equiv. ft. water
pipe @.005
= 00.19 PSI
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TOTAL
= 14.16 PSI
d) Add total friction loss to tank
loss (1 PSI)
= 15.16 PSI
total loss
e. Check elevation of ratio controller (should be level with top of
tank in most cases). Note: This
example assumes that the concentrate controller is level with
the top of the tank.
f. Check total loss established
above (15.16 PSI), against the
minimum flow metering pressure drop of the 4" concentrate
controller.
This is accom-
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BS
Step 6. Select The Size And Type of
Foam Concentrate Bladder Tank
a. Size bladder tank - total system
demand X percentage X duration X 1.15 or 1050 GPM X 10
minutes X .03 X 1.15 = 362
gallons. (Refer to tank size tables for selection). No 362
gallon tank is available so always select the next larger
size, or a 400 gallon tank.
Step 7. Size Tank Water Supply And
Foam Concentrate Discharge
Pipe Sizes
a. "D" dimension on the concentrate controller chart calls for a
minimum pipe size of 1 1/2"
diameter pipe.
Step 8. Position Bladder Tank And
Proportioner
a. The example in Figure 3 requires that the bladder tank
be located more than 50
equivalent feet away from the
proportioner
b. Calculate foam concentrate flow
through 1 1/2" concentrate piping at minimum 4" concentrate
controller flow of 375 GPM (see
table on page 103) 3% of 375
GPM = 11.3 GPM is the minimum concentrate flow required
for 4" concentrate controller to
proportion ATC properly. This
is also the amount of water
which will flow through the tank
water supply piping to displace
the foam concentrate flowing
into the concentrate controller.
FOAM CONCENTRATE
CONTROL SYSTEM (CCS)
DESIGN AND
CALCULATIONS
FIGURE 3
EQUIVALENT LENGTH FOR:
TANK WATER SUPPLY PIPING
3 -1 1/2 90° elbows in tank water Supply (3 ea @ 4 ft)
1 -Tank water supply length (sch 40; c=120)
1 -Full port ball valve (tank water supply)
=
=
=
12 ft.
25 ft.
1 ft.
Total equivalent feet of 1 1/2" water piping
=
38 ft.
1-1 1/2 Viking E-1 Halar® coated deluge CCV
1 -1 1/2 " swing check valve
3 -1 1/2 90° elbows in concentrate line (3 ea @ 4 ft)
1 -Concentrate line pipe length (sch 40, c=120)
1 -full port ball valve (foam concentrate supply)
=
=
=
=
=
10 ft.
9 ft.
12 ft.
25 ft.
1 ft.
Total equivalent feet of 1 1/2 concentrate piping
=
57 ft.
FOAM CONCENTRATE DISCHARGE PIPING
April 16, 1998
100e
FOAM CONCENTRATE
CONTROL SYSTEM (CCS)
DESIGN AND
CALCULATIONS
R
DESIGN DATA
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Note: Should your calculations indicate
that a higher than minimum flow is
required for balancing purposes, there
are several methods which may be
used to reduce the flow to the minimum concentrate controller flow and
still achieve balanced pressures. Use
one or more of the following methods
to achieve balanced pressures.
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1. Increase pipe sizing
2. Lower the elevation of the concentrate controller*
(note: for every 1"-0" of drop in elevation you lower the concentrate controller, a gain of approximately .43 PSI may be realized. However, there must
still be a minimum of 4 to 5 pipe
FIGURE 4
TANK WATER SUPPLY PIPING
3 -1 1/2 90° elbows in tank water supply (3 ea @ 4 ft)
1 -Tank water supply length (sch 40; c=120)
1 -Full port ball valve (tank water supply)
=
=
=
12 ft.
25 ft.
1 ft.
Total equivalent feet of 1 1/2" water piping
=
38 ft.
FOAM CONCENTRATE DISCHARGE PIPING
1 - 3" Viking E-1 Halar coated deluge CCV
1 -3 " swing check valve
3 -3" 90° elbows in concentrate line (3 ea @ 7 ft)
1 -Concentrate line pipe length (sch 40, c=120)
1 -full port ball valve (foam concentrate supply)
=
=
=
=
=
29 ft.
16 ft.
21 ft.
25 ft.
1 ft.
Total equivalent feet of 3" concentrate piping
=
92 ft.
Form No. 082494
diameters of straight pipe maintained on the inlet and outlet
sides of the concentrate controller).
3.Try to use fewer elbows or tees,
if possible to keep the tank
water supply piping and concentrate supply piping as
straight as possible.
4.Install tank and controller closer
together.
5.Use a full port ball valve with a
diaphragm actuator (a very expensive alternative) as the concentrate control valve.
*An automatically actuated concentrate control valve must be
used when lowering the concentrate controller below top of
tank. This prevents possible
foam migration or siphoning of
foam into system riser. It is
good engineering practice to
use an automatically actuated
concentrate control valve in all
foam/water systems. The system hydraulic calculations must
always include the friction loss
for the selected concentrate
controller. This loss can be
found by establishing the total
system flow through the controller from the final system hydraulic calculations, then plotting the point across the concentrate controller permanent
pressure drop table found on
page 104, until it intersects the
selected concentrate controller
size curve. Then read straight
across the table to the left to
find the permanent pressure
drop for the selected concentrate controller. This loss must
never exceed 10 PSI. If it does,
select the next larger size controller.
TE
will indicate the minimum flow
which must pass through the
concentrate controller in order
to have balanced pressures at
both the foam concentrate inlet
to the controller, and through
the waterway of the controller.
Drop a line through the new plot
point straight down the graph to
establish the minimum flow to
achieve balanced pressure at
the controller. If this flow is
equal to or less than the minimum flow indicated in the table
found on page 103, then the
pipe sizes may remain unchanged. (in this case, the
minimum balance flow is 410+
GPM, which is higher than the
minimum flow we are looking
for, but is within a 2 psi balance
of 7.5 psi minimum loss, therefore it should be within acceptable industry standards.
BS
.088 PSI/ft (The friction loss
for ATC foam concentrates is
very different from AFFF.
For ATC type foam concentrates, refer to the appropriate friction loss table for the
type of ATC foam being
used).
Total pressure loss
for 92 equivalent ft
of foam concentrate
discharge piping
x .088
= 8.1 PSI
Total pressure loss
for 38 equiv. ft.
water pipe @.005 = 0.19 PSI
TOTAL
= 8.29 PSI
d. Add total friction loss to tank loss
(1 PSI)
= 9.29 PSI
total loss
e. Check elevation of ratio controller (should be level with top of
tank in most cases). Note: This
example assumes that the concentrate controller is level with
the top of the tank.
f. Check total loss established
above (9.29 PSI), against the
minimum flow metering pressure drop of the 4" concentrate
controller.
This is accomplished by referring to the metered pressure drop table for
the 4" concentrate controller
selected (see page 104 in the
"Tank and Proportioner" section of the foam data book).
Now plot the 9.29 PSI drop on
the metering pressure drop until it intersects the 4" ratio controller flow line. This plot point
The above calculations are only an
estimate of the actual friction
losses, and must be verified by actual system field flow testing.
If further adjustments are necessary,
contact your Viking representative for
possible modifications and recommendations. For actual system requirements,such as densities, areas of operation, foam concentrate supplies, water
supplies, and other specific information,
consult the proper standards and
Authorities Having Jurisdiction.
Replaces pages 100a-e d with dates prior
to April 16, 1998. Re-dated pages