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Pumping Apparatus
Pumping Apparatus chapter 6
| Question | Answer |
|---|---|
| Modern extinguishing agents 1___2___3____4____ | Dry Chemicals, Dry Powders, Foam concentrates, and halogenated hydrocarbons |
| _____ remains the most commonly used fire extinguishing agent | Water |
| _____ is a compound (molecule) of hydrogen and oxygen formed when two hydrogen atoms (h2) combine with one oxygen atom (O) | Water |
| Between ___ and ___ water exists in a liquid state | 32 degrees F and 212 degrees F |
| Water density, or its weight per unit volume, is measured in _____ | Pounds per cubic foot |
| Water is heaviest close to its | Freezing point |
| Water is lightest close to its | boiling point |
| For fire protection purposes, ordinary fresh water is generally considered to weigh ___ lb/ft3 or ___ lb/gal | 62.5 or 8.33 |
| The primary way water extinguishes fire is | by cooling or absorbing heat from the fire |
| Another way water extinguishes fire is | smothering |
| Smothering also occurs to some extent when water | converts to steam in a confined space |
| As a extinguishing agent, water depends on the following | Specific heat, Latent Heat of Vaporization, Exposed Surface Area, Specific Gravity |
| ____ and ___ of Vaporization govern the heat absorbing ability of water | Specific Heat and Latent Heat |
| The amount of ____ of the water exposed to the heat dictates the amount of heat the water will absorb | surface area |
| _____ determines whether water will float on the surface of another liquid or vice versa | Specific gravity |
| _____ is a measure of the heat absorbing capacity of a substance | Specific Heat |
| A ___ is the amount of heat required to raise the Temp of 1 pound of water 1 degree F (starting at 60 degrees) | BTU |
| The ____ also a unit of work, has taken the place of the calorie in the SI (International System of Units) heat measurement | Joule |
| water absorbs ___ times as much heat as does an equal amount of carbon dioxide | five |
| The ____ is the quantity of heat absorbed by a substance when it changes from a liquid to a vapor | latent heat of vaporization |
| The Temp at which a liquid absorbs enough heat to change to vapor is known as ______ | Boiling Point |
| At sea level water begins to boil or vaporize at | 212 degrees F |
| Each pound of water requires approximately ___ BTU of additional heat to completely convert into steam | 970 |
| 1 gallon of water absorbs ____ BTU getting to 212 Degrees F | 1,266 |
| A gallon of water weighs | 8.33 pounds |
| 1 gallon of water will absorb ___ BTU of heat if all water is converted to steam | 9,346 |
| The speed with which water absorbs heat ____ in proportion to the water surface exposed to the heat | increases |
| If water is divided into many drops, the rate of heat absorption _____ hundreds of times | INCREASES |
| At 212 degrees F water expands approximately ____ its original volume | 1,700 |
| water can also ____ fire when it floats on liquids that are heavier than water, such as carbon disulfide | smother |
| _____ is the tendency of a liquid to posses internal resistance to flow | Viscosity |
| The density of liquids in relation to water in knwn as ___ | specific gravity |
| Water is given a value of 1. liquids with a specific gravity less than 1 are ___ lighter than water and will ____ on water. Those with a specific gravity greater than 1 will ___ | float, sink |
| Most flammable liquids have a specific gravity of | less than 1 |
| Advantages of water 1-5 | 1. has greater heat absorbing capacity than other agents 2. Large amount of heat to change water into steam, more heat absorbed 3. the greater surface area exposed, more heat absorbed 4. occupies 1700 times original volume 5. water is plentiful & cheap |
| Disadvantages 1-5 | 1. higher surface tension 2. may be reactive to certain fuels 3. low opacity & reflectivity, radiant heat easily pass through 4. freezes at 32 5. conducts electricity |
| ____ a force per unit area | pressure |
| pressure may be expressed in | pounds per square foot ( psf) pounds per square inch (PSI) kilopascals (KPa) |
| ____ measure of weight | Force |
| (1x1x1) containing 1 cubic foot of water and weighing _____ | 62.5 LBS |
| 1 square foot contains ____ inches | 144 |
| Because 1 square foot contains 144 square inches the weight of water in a 1 square inch column of water 1 foot high equals 62.5 lbs divided by 144 square inches or _____ | 0.434 lbs |
| A 1 square inch column of water 1 foot high therefore exerts a pressure at its base of | 0.434 psi |
| The height required for a 1 square inch column of water to produce 1 psi at its base equals 1 foot divided by 0.434 psi/ft or 2.304 feet; therefore 2.304 feet of water column exerts a pressure of ___ psi at its base | 1 |
| a cube that is 0.1m x 0.1m x 0.1m holds ___ liter of water | 1 |
| the weight of 1 liter of water is __ kilogram. the cube of water exerts 1 KPa (1kg) of pressure at the bottom of the cube | 1 |
| One cube meter of water holds ____ liters of water and weighs ___ kg | 1000 |
| The cube meter of water is comprised of 100 columns of water, each 10 decimeters tall, each column exerts ___ KPa at its base | 10 |
| The speed at which this fluid travels is often referred to as | Velocity |
| There are ___ basic principals that determine the action of pressure upon fluids | 6 |
| First principal | fluid pressure is perpendicular to any surface of which it acts. |
| Second principal | Fluid pressure at a point in a fluid at rest is the same intensity in all directions. To put it another way, fluid pressure at a point in a fluid at rest has no direction |
| third principal | Pressure applied to a confined fluid from without is transmitted equally in all directions. |
| Fourth principal | The pressure of a liquid in an open vessel is proportional to is depth |
| Fifth principal | the pressure of a liquid in an open vessel is proportional to the density of the liquids |
| Sixth principal | the pressure of a liquid on the bottom of a vessel is independent of the shape of the vessel |
| Atmospheric pressure is greatest at ___ altitudes | low |
| Atmospheric pressure is least at ___ altitudes | very high |
| At sea level the atmosphere exerts a pressure of ___ which is considered standard atmospheric pressure | 14.7 psi |
| A common method of measuring atmospheric pressure is by comparing the weight of the atmosphere with the weight of ____ | mercury |
| In a vertical cylinder, the greater the atmospheric pressure the ___ the column of mercury | taller |
| A pressure of 1 psi (6.90KPa) makes the column of mercury about ____ inches (52mm) tall | 2.04 |
| At sea level the column of mercury is 2.04 x 14.7 or ____ inches | 29.9 |
| The reading of most pressure gauges are psi (or KPa) in addition to the _____ | existing atmospheric pressure |
| a gauge reading 10 psi at sea level means that the pressure actually is _____ | 24.7 psi (170 KPa) (14.7 + 10 or 100 + 70 KPa) |
| Any pressure less than atmospheric pressure is called | vacuum |
| absolute zero pressure is called | a perfect vacuum |
| In the fire service, gauge reading less than 0 psi (KPa) are often referred to by the misnomer _____ | negative pressure |
| _____ in the fire service refers to the height of a water supply above the discharge orifice | head |
| to convert head in feet to head pressure divide the number of feet by ____ (the number of feet that 1 psi will raise 1 square inch column of water | 2.304 |
| The water flow definition of ____ is stored potential energy available to force water through pipe, fittings, fire hose, and adapters. | Static pressure |
| Static means | at rest or without motion |
| A ___ pressure is seldom found in municipal water systems because there is always some flow in the pipes due to normal domestic or industrial use | truly static pressure |
| ____ is that pressure found in a water distribution system during normal consumption demands | Normal operating pressures |
| The difference between static pressure and normal operating pressure is the | friction caused by water flowing through the various pipes, valves, and fittings in the system |
| _____ is that art of the total available pressure not used to overcome friction loss or gravity while forcing water though pipe fittings, fire hose, and adapters | Residual Pressure |
| Residual means | a remainder or that which is left |
| _____ is that forward velocity pressure at a discharge opening while water is flowing | Flow pressure |
| ____ refers to the center line of the pump or the bottom of a static water supply source above or below ground level | Elevation |
| ____ is the position of an object above or below sea level | altitude |
| When the nozzle is above the pump there is a pressure ____ | loss |
| When the nozzle is below the pump there is a pressure | gain |
| Both pressure loss and pressure gain are referred to as _____ | elevation pressure |
| Altitude affects the production of fire streams because atmospheric pressure drops as height above sea level increases. This pressure drop is of little concern to about _____ | 2000 feet |
| Above sea level, atmospheric pressure decreases approx ___ for every 1000 feet | 0.5 psi ( 3.5 KPa) ` |
| The fire service definition of _____ is that part of the total pressure lost while forcing water through pipe, fittings fire hose and adapters | Friction loss |
| In a fire hose the following 6 causes friction loss | 1. Movement of water molecules against each other 2. Linings in fire hose 3. Couplings 4. Sharp bends 5. Change in hose size or orifice by adapters 6. Improper gasket size |
| The friction loss in old hose may be as much as ____ greater than new hose | 50% |
| The rougher the inner surface of the pipe (commonly referred to as the ____) the more friction loss that occurs. | Coefficient of friction |
| There are ____ basic principals that govern friction loss in fire hose and pipes | four |
| First Principle in friction loss | If all other conditions are the same, friction loss varies directly with the length of the hose or pipe. |
| Second Principal in friction loss | When hoses are the same size, friction loss varies approximately with the square of the increase in the velocity of the flow |
| Third Principal in friction loss | For the same discharge, friction loss inversely as the fifth power of the diameter of the hose, this principle readily proves the advantage of larger hose |
| Fourth Principal in friction loss | For a given flow velocity, friction loss is approximately the same regardless of the pressure on the water. |
| Friction loss in a system increases as the length of the hose or piping ____ | increases |
| A open fire hose means | open butt |
| If the velocity is increased beyond limits, the friction becomes so great that the entire stream is agitated by resistance. This agitation causes a degree of turbulence called___ | Critical velocity |
| Certain characteristics of hose layouts affect friction loss including ____,____,____ | Hose length, Hose diameter, Sharp bends (kinks in the hose |
| Realistically, hose larger than ___ inches in diameter cannot be used for handlines | 3 inches |
| Suddenly stopping water moving through a hose or pipe results in a energy surge being transmitted in the opposite direction, often at many times the original pressure. This surge is referred to as ____ | water hammer |
| The intricate working parts of a water system are many and varied. Basically the system is composed of the following ____,____,____,____ | Source of water, Means of moving water, Water processing or treatment facilities, water distribution system, including storage |
| Means of water movement ___,___,____ | Direct pumping system, gravity system, Combination system |
| ____ uses a primary water source located higher elevation than the distribution system | Gravity system |
| The primary water supply can be obtained from ether ____or____ | surface water or ground water |
| Most communities use a combination of the direct pumping and gravity systems. In most cases ____ supply the gravity flow | elevated storage tanks |
| When the system pressure is high during periods of low consumption, ____ open and allow the elevated storage tanks to fill | automatic valves |
| Elevated storage tanks serve as a ____ and provide adequate pressure though the use of gravity | Emergency storage |
| There is much less pressure loss in a water distribution system when fire hydrants are supplied from ____ | two or more directions |
| A fire hydrant that is supplied from one direction is know as ____ | dead end hydrant |
| when a fire hydrant receives water from two or more directions is said to have ____ or a ____ | circulating feed or looped line |
| A distribution system that provides circulation feed from several mains constitutes a ____ | grid system |
| Primary Feeders | Large pipes (mains) with relatively widespread spacing, that convey large quantities of water to various points of the system for local distribution to the smaller mains |
| Secondary Feeders | Network of intermediate sized pipes that reinforce the grid |
| Distributors | Grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers |
| To ensure sufficient water, two or more ____ should run from source of supply to the high risk and districts of the community be separate routes | primary feeders |
| In residential areas the recommended size for fire hydrant supply mains is at least ___ in diameter. There should be ___ cross connecting mains at intervals of no more than ___ | 6 inches, 8 inches, 600 feet |
| In a business and industrial district, the minimum recommended size is an ___ main with cross connecting mains every ___ | 8 inch, 600 feet |
| ____ mains may be used on principal streets and in long mains not cross connected at frequent intervals | 12 inch |
| Water mains as large as ___ may be found in major cities | 48 inch |
| The function of a valve in a water distribution system is to | provide a means for controlling the flow of water through the distribution piping |
| Valves should be operated at least ____ to keep them in good condition | once a year |
| Valves for water systems are broadly divided into ____and ____ | indicating and non indicating types |
| Two common indicator valves are the ____ and the ___ | post indicating valve (PIV) and the outside screw and yoke (OS&Y) valve |
| _____is a hollow metal post that is attached to the valve housing. The valve stem inside this post has the words open and shut printed on it | Post indicating valve |
| The ____ has a yoke on the outside with a threaded stem that controls the gates opening or closing | OS&Y (outside screw and yoke) |
| OS&Y- the threaded porting of the stem is out of the yoke when the valve is ___ and inside the yoke when the valve is ___ | open, ---- inside the yoke when the valve is closed |
| these valves most commonly used on sprinkler systems | OS&Y |
| _____in a water distribution system are normally installed in valve boxes or manholes | Non indicating valves |
| These valves are the most commonly used in public water distribution systems | Non indicating valves |
| Control valves in water distribution systems may be either ____ or ___. Both valves can be indicating or non indicating types | gate of butterfly valves |
| Water pipe that is used underground is generally made of ___,___,___,___,___,or____ | cast iron, ductile iron, asbestos cement, steel, plastic, or concrete |
| ______Is the average of the total amount of water used in a water distribution system over the period of one year | average daily consumption |
| ____ is the maximum total amount of water that was used during a 24 hour interval within a 3 year period | Maximum daily consumption |
| ___ is the maximum amount of water used in any 1 our interval over the course of a day | peak hourly consumption (PHC) |
| The maximum daily consumption is normally about ___ time the average daily consumption | 1 1/2 |
| The peak hourly rate normally varies from __ to ___ times the normal hourly rate | 2 to 4 |
| The private water supply system exists for one of the 3 purposes | 1. to provide water strictly for fire protection, 2. to provide water for sanitary and fire protection . to provide water for fire protection and manufacturing process |
Created by:
turneyj