Pump Manual Flashcards
Atmospheric pressure
14.7
Affects amount of vacuum that can be generated inside a pump and how high water can be drafted
Dependable lift
height that a column of water can be lifted to provide a reliable fire flow
14.7 ft at sea level
Dual pumping
Using a strong hydrant to supply two pumpers by connecting intake to intake
Eductor rate (ED)
Application % for eductors:
3% for hydrocarbons
6% for polar solvents
Class A: 0.1 - 1.0%
FDC standard pressure for spinklers
150 PSI
Fire Load
Avg weight lbs/sqft of contents of a room
Avg begroom has 4.3 lbs/sft
Head pressure
For every 1’ increase in elevation .434 PSI increase
e.g. 5 lbs per floor
Master stream
large caliber hose that flows 350 GPM or more
Max dependable flow
75% of the total capacity of an engine
this is the max flow for an engine during a relay operation
Needed Fire Flow (NFF)
The amount of water (in GPM) needed to control the fire within 1 min
Normal operating pressure
Pressure in a water system during regular domestic consumption
Parallel (Volume) mode
In a two-stage pump, source water flows from intake into the eye of both impellers simultaneously
Each impeller pumps 50% of that rated GPM capacity of the pump
Priming Pump
Positive displacement pump that pumps air out of centrifugal pumps…when activated, reduces pressure inside pump below 14.7 (atmospheric pressure)
Pump Discharge Pressure Formula
PDP = NP + FL +- EP + AFL
Reasonable Efficiency
% of water that is actually converted into steam in a fire = 80%
Series (Pressure) mode
First stage impeller increases pressure and dishcarges 50-70% of the volume capacity through the transfer valve and into the eye of the 2nd impeller
Static pressure
Stored potential energy available to force water through pipes, fittings, fire hose, and adapters while water is at rest
Tandem pumping
Short relay. Pumper at water source pumps to the intake of second pumper.
Used when pressures higher than the capabilities of a single pump are required.
Theoretical lift
Theoretic height that a column of water can be lifted by atmospheric pressure in true vacuum
33.9 ft at sea level (14.7 x 2.304 psi = 33.9)
Type 1 Pumper
100% of its rated capacity at 150 psi
70 % of its rated capacity at 200 psi
50% of its rated capacity at 250 psi
Measured from draft lifting water at least 10 ft
Max GPM for handline
350 gpm above this creates too much of NR
Nozzle Pressure - Smooth Bore
Handline: 50 psi
Master stream: 80 psi
Solid Bore tip sizes
15/16”
1”
1 1/8”
1 1/4”
Solid Bore Handline - Tip sizes and GPMs
15/16” –> 185 GPM*
1” –> 210 GPM
1 1/8” –> 265 GPM
1 1/4” –> 325 GPM*
*Breakaway nozzle diameter for our 1 3/4” and 2 1/2” pre-connects
Solid Bore Master Stream - Tip sized and GPMs
1 3/8” —> 500gpm
1 1/2” —> 600gpm
1 3/4” —> 800 gpm
2” —> 1000 gpm
Specialty nozzles - flow and nozzle pressure
Piercing — 125 gpm @ 100psi
Cellar — 250 gpm @100 psi
Chimney — 1-3gpm @ 100 psi
Master stream foam – 350gpm @ 100 psi
All are pumped at 100psi at the tip
pg 20
Weight of 1 cubic foot of water
62.4 lbs
Gallons in 1 cubic foot
7.48
Weight of 1 gal
8.34 lbs
Parallel hose lines reduce friction loss by what %?
75%
1 cubic foot of water expands to how many of steam at 212 degrees?
1700 cubic feet
1 gal water expands to how many cubic feet of steam at 212?
227
1 gal will absorb all of the heat that can be produced with available oxygen in how many cubic ft of air?
200
Needed Fire Flow (NFF)
NFF = [ (length x width) / 3 ] x % involvement
7 types of pressure: Atmospheric
Pressure exerted on surface of earth by weight of air
- 14.7 PSI at sea level (decreases w/ increase in elevation; 1 PSI of atmosphere will raise a column of water 2.31 ft)
- Feet of water 33.9ft theoretical lift (14.7 psi x 2.31ft = 33.9)
- good pumper max lift = 22-25ft
- dependable lift = 14.7ft - Hg = 30 inches (inches of mg in vacuum gauges) – pumpers in good condition can create vacuum of 22” mg
- 1” mg on the pump vacuum gauge = 1.13 ft column of water can be lifted (1.13 x 22 = 25ft max lift)
pg 12
7 types of pressure: Elevation Pressure
0.434 psi / ft
or
5 psi / floor
pg 12
7 types of pressure: flow pressure
measurement of water coming from a discharge opening (reading on pressure gauge)
pg 12
7 types of pressure: head pressure
refers to the height of a water supply above the discharge
Convert feet to head by dividing feet by 2.304
1 / 0.434 = 2.304
pg 12
7 types of pressure: normal operating pressure
Pressure in a water system during normal consumption demands; once water starts flowing we no longer have static pressure. Difference between static pressure and NOP is friction loss
pg 12
7 types of pressure: Residual pressure
Pressure remaining in the system after water is flowing (used to estimate additional flow capacity)
pg 12
7 types of pressure: static pressure
pressure when water is not flowing; this is the pressure you read on the fire pump when no discharges are open
pg 12.
10/15/25 rule
10% drop from initial residual compound reading = additional 3x the current GPM flow
15% drop = additional 2x the current GPM flow
25% drop = additional 1x the current GPM flow
pg 13
Principle #1: friction loss varies directly with the length of the hose or pipe
double the length of the hose = double the friction loss
pg 24
Principle #2: When hoses are the same diameter, friction loss varies with the square of the increase in flow (gpm)
Double the flow = quadruple the friction loss
pg 24
Principle #3: For same discharge, friction loss varies inversely as the fifth power of the diameter of the hose
The smaller the diameter, the greater the friction loss
Principle #4: For a given velocity flow, friction loss is approx the same regardless of pressure on the water
Friction loss is caused by speed of water, not the pressure
Parallel hose lines - effect on friction loss
Compared to a single line:
2 lines = 1/4 the FL
3 lines = 1/9 the FL
4 lines = 1/16 the FL
Friction loss multipliers (M) by hose diameter
1" ---> 150 1 3/4" ---> 10 2 1/2" ---> 2 3" ---> 1 4" ---> 0.2 (divide by 5) 5" ---> 0.05 (divide by 20)
Elevation pressure when distance above pump is known
EP = 0.434 x H
As a rule, add 5 psi for every 10 feet elevation above pump, reduce psi by 5 for every 10 ft drop below pump
Appliance Friction Loss - standpipe
<350 GPM => 10 psi
>350 GPM => 25 psi
Appliance Friction Loss - master stream (ladder pipes, deck guns, blitz fire)
25 PSI for all GPM
- by definition master stream is flowing >350
Appliance friction loss for appliances (wyes, siamese, manifold)
<350 gpm => 0 psi
>350 gpm => 10 psi
Appliance friction loss - foam eductor
50 psi
Wyed lines with equal length, diameter and GPM
- Add GPM for all nozzles and use as Q for calc’ing FL in supply line
* 2. If total GPM >350, add 10 psi FL for wye appliance* - Calc FL in supply line
- Calc FL for one discharge
- Calc PDP by adding FL for supply and one discharge
Wyed lines with unequal length, diameter, GPM flow
Same as equal length/diameter, flow, except:
Figure PDP by adding FL for supply + highest pressure handline….gate down lower pressure handline at the wye
PDP for spinklers
GPM = 0.5 x P + 15 P = sprinkler head pressure (typically 7-10 PSI)
Each open sprinkler head requires 20 GPM
Starting pressure should be 150 psi
Three types of standpipes
Class 1: 2 1/2” outlets for firefighting
Class 2: 1 1/2” hose outlets for occupant use
Class 3: Combination standpipe, integrates class 1 and class 2
Appliance friction loss when pumping an aerial lader
25 psi for waterway piping
+
25 psi for master stream appliance
Minimum intake residual pressure
20 psi
Maximum net PDP
180 PSI
= 250 PSI pump rating - 50 PSI safety - 20 PSI intake residual = 180 PSI
Estimating needed fire flow (NFF) in a relay
NFF = ( L x W x % involvement ) / 3
Calculating max distance between pumpers in a relay
Max distance = (165 / FL ) x 100
FL is for 100 ft section
165 and 100 are constants
Calculate # of pumpers needed in a relay
= ( Total distance of relay / Max distance ) + 1
How much 5” LDH does an engine carry?
900’
NFPA standard for max dependable flow for a relay pumper
75% of its rated capacity at draft
Types of foam systems on our apparatuses
CAFS
Foam Pro
Husky
Perce Quantum system
Generally we carry 40 gallons of Class A or Novacool; some engines carry three 5 gal buckets of AFFF for class B
Class A Foam mechanism of action
It attracts carbon
It decreases surface tension of water
Raises moisture content of wood up to 50%
Absorbs 3x the BTUs compared to water alone
Class B Foam Mechanism of action
Repels carbon
Forms a film that hovers over a spill
Prevents vapor production and ignition
Eductor rates for Class A foam
Initial attack: 0.5%
Overhaul: 0.2%
Exposure protection: 1.0%
Wildland pre-treating: 0.1-0.2%
3-2-1 rule for foam
When flowing 1 3/4” handline using a portable eductor
- No more than 300’ of hose past the eductor
- 200 PSI to the eductor inlet
- Utilizing 100 PSI nozzle
Application rates for novacool
Fire attack: 0.4%
Overhaul and brush fires: 0.1%
Iowa Formula
GPM = ft3 involved / 100
Needed Fire Flow (NFF)
NFF = LxW/3 x % of involvement
Total water needed
Area x FLD x BTU ÷ 9,343
Properties of water #1
Fluid pressure is perpendicular to
any surface on which it acts.
(
Properties of water #2
When a fluid is at rest, fluid pressure
is the same in all directions.
(testing fire hose)
Properties of water #3
When there is an increase in
pressure at any point in a confined fluid, there
is equal increase at every other point in the
container. (This is known as Pascal’s Law)
(This principle is important in firefighting hydraulic systems acts as a whole)
Properties of water #4
The downward pressure of a
liquid in an open vessel is proportional to its
depth.
(pressure at standpipe floor 5 would be higher than fl 3 to overcome head pressure)
Properties of water #5
The downward pressure of a liquid
in an open vessel is proportional to the liquid
density.
Properties of water #6
The downward pressure of a liquid
in an open vessel is not affected by the shape of
the container
Volume of a Rectangular Container
Volume = L x W x H
Volume of a Cylindrical Container
Volume = .7854 x D² x H
Calculating Volume of Hose Lines
Volume = .7854 x D2 x L x 12 (same as cylinder calculation)
Calculating Gallon Capacity of Containers
Gallon Capacity for a Rectangular Container
Gallon capacity = 7.48 x V
Calculating Gallon Capacity of Hose
Gallon capacity = V ÷ 231 (number of cubic inches in a gallon
Weight for a Rectangular Container
Weight = (L x W x H) x 62.4 (weight of 1 cubic foot of water)
Calculating Weight of a Hose Line
Weight = number of gallons x 8.34 lbs (weight of 1 gallon of water)
Freemans Formula
GPM = 29.7 x D² x √NP (calculates flows for smoothbore discharge nozzels)
Nozzle Reaction for Fog Nozzles
NR = .0505 x Q x √NP (at straight stream
position)
Nozzle Reaction for Smooth Bore Nozzles
NR = 1.57 x D² x NP
greatest horizontal reach
32deg
