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Flashcards in Ch. 5 Principles of water Deck (26)
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1
Q

Ch 5. pg. 176

The difference between static pressure and normal operation pressure is the ______ caused by water flowing through the pipes, valves and fittings of the system.

A. resistance

B. pressure

C. friction

D. velocity

A

C. friction.

2
Q

Ch. 5 pg. 176 What are pressure losses or gains due to gravity called? A. altitude adjustments B. Elevation pressure C. Head pressure D. flow pressure

A

B. elevation pressure.

3
Q

Ch. 5 pg. 177 An important factor in operating a fire pump and producing effective fire streams is the loss of pressure in a pipe or hose due to friction. What are the causes of friction loss in a fire hose: (6)

A

-movement of water molecules against each other -linings of fire hose/ delaminating hose -couplings -sharp bends/kinks -change in hose size or orifice by adapters -improper gasket size.

4
Q

Ch. 5 pg. 184 Grid system uses water supply system that utilizes ______ for improved distribution. A. primary feeders B. Lateral feeders C. horizontal feeders D. distribution lines.

A

B. lateral feeders lateral lines consist of Feeder lines Secondary feeders Distributors lines

5
Q

ch. 5 pg. 186 type of valve used to control underground water mains found on the supply main of installed fire protection systems. the operating stem of the valve extends above the ground. A. Outside screw and yoke valve B. Non indicting valve C. indicating valve D. post indicator valve.

A

D. post indicator valve

6
Q

Ch. 5 pg. 186 valves in private fire protection systems are usually of the _____ type. A. OS&Y valve B. Post indicator valve C. Indicating valve D. non indicating valve

A

C. indicating valve post-indicator valve and OS&Y valves are both indicating valves

7
Q

Ch. 5 pg. 186 Most common type of valve used on public water distribution systems. A. non indicating valve B. indicating valves C. Post indicator valves D. OS&Y valve

A

A. non indicating valve

8
Q

CH. 5 pg. 189 What is an efficient and economical extinguishing agent? A. class A foam B. Class B foam C. Water D. Dry chemical extinguishers.

A

C. water.

9
Q

p.167 Characteristics of Water Ordinary fresh water weighs? +__Per cubic Foot and __per gallon

A

62.4 lbs per cubic foot 8.3 lbs per gallon

10
Q

p.169 Advantages and Disadvantages of Water Advantages: +Can be used to smother fires in combustible liquids whose specific gravity is___. +At 212 F water converted to steam occupies ___ times its original volume. Disadvantages: +Has a high surface tension and may require__ agents to be mixed to increase its penetrating ability.

A

Greater than 1

1,700

Wetting

11
Q

p.170 Water Pressure and Velocity

___ is measured in PSF/PSI and is the force per unit area exerted by a liquid or gas. ___ is a simple measurement of weight usually in pounds and directly related to the force of gravity, the amount of attraction the earth has for all bodies. +The force exerted by water is based on the impact of its __ within a specific area.

A

Pressure

Force

Weight

Note:Force is an influence that causes a change in speed,direction or shape of a substance

12
Q

p.172 Principles of Pressure +The speed at which a fluid travels through a hose/pipe, determined by pressure and orifice size. 1.First Principle= 2.Second Principle= 3.Third Principle= 4.Fourth Principle= 5.Fifth Principle= 6.Sixth Principle=

A

Velocity 1.Fluid pressure is perpendicular to any surface on which it acts. 2.Fluid pressure at a point in fluid at rest is the same intensity in all directions.(Used in hydrostatic testing) 3.Pressure applied to a confined fluid is transmitted equally in all directions. 4.The pressure of a liquid in an open vessel is proportional to its depth. 5.The pressure of a liquid in an open vessel is proportional to the density of the liquid. 6.The pressure of a liquid at the bottom of a vessel is independent of the shape of the vessel.

13
Q

p.174 Atmospheric Pressure (14.7psi at sea level) +The atmospheric pressure that surrounds the Earth has __and__, exerting pressure on everything. +Pressure is greatest at __ altitudes and lowest at __altitudes. +Any pressure less than atmospheric pressure is called ___.The PSI above a perfect vacuum is___ zero.

A

Depth and Density Low High Vacuum Absolute

14
Q

p.175 Types of Pressure ____refers to the height of a water supply above the discharge orifice. +Head in ft to head in pressure= Feet/2.304 +For every 1 ft increase in elevation,0.434 psi is gained)

A

Head

15
Q

p.175 Types of pressure

+Water flow definition is stored potential energy available to force water through pipes,fittings, hose and adapters is called___?

+Water pressure may be produced by?(3)

A

Static Pressure

  1. Elevated Water Supply
  2. Pumps
  3. Atmospheric Pressure
16
Q

p.176 Types of Pressure

+The pressure found in a water distribution system during normal consumption demands.

+Pressure at the test hydrant while water is flowing/Portion of the total available pressure not used to overcome friction loss.

+The forward velocity pressure of the water flowing from a discharge opening. Found by using pitot tube.

A

+Normal Operating Pressure (Difference between static and NOP is the friction)

+Residual Pressure

+Flow Pressure(Velocity Pressure)

17
Q

p.179 Pressure Loss and Gain

+Refers to center line of pump or bottom of a static water source and is the height of a point above sea level or some other reference point. +Geographic position of a location or object in relation to sea level, can be above, below or at sea level.

+The pressure loss or gain due to gravity and elevation changes.

+Above___feet, the lessening of atmospheric pressure means pumpers must work harder. +Above sea level, atmospheric pressure decreases __psi for every__feet.

A

+Elevation

+Altitude

+Elevation pressure

+2,000 +0.5 psi, 1,000 feet

18
Q

p.179 Pressure Loss and Gain +Refers to center line of pump or bottom of a static water source and is the height of a point above sea level or some other reference point. +Geographic position of a location or object in relation to sea level, can be above, below or at sea level. +The pressure loss or gain due to gravity and elevation changes.

A

+Elevation +Altitude +Elevation pressure

19
Q

p.177 Friction Loss +The loss of pressure created by the turbulence/friction of water moving against the interior walls of hose or pipes.

+The Coefficient of Friction

A

+Friction Loss

+The rougher the inner surface,the greater the friction loss.

20
Q

p.178 Applying friction loss principles

+How much pressure is required to reduce waters volume 1%?

+The__ of hose determines the velocity for a given volume of water.

+Once the degree of turbulence becomes too great, known as___velocity, it is necessary to use parallel hoselines or siamese lines to increase flow and reduce friction.

A

+30,000 psi

+Diameter

+Critical

21
Q

p.183 +This estimate is the total amount of water needed for domestic and industrial use and for fire fighting use.

A

+Engineering Estimate

22
Q

p.186 Water Main Valves

+These valves are used to stop flow at specified points and should be inspected and operated yearly by the ____utility.

+Indicating Valves: 2 types -

A

+Water supply

post-indicator valve

outside screw and yok valve

23
Q

p.188 +What is a way to reduce a pipe from encrustation and sedimentation?

A

+Flushing hydrants periodically

24
Q

p.188 Water System Capacity

+Amount of water used per day based on the total amount used over a period of 1 year.

+Total amount of water that was used during any 24 hour interval within a 3 year period.

+Maximum amount of water used in any 1 hour interval over the course of a day.

A

+Average Daily Consumption

+Maximum Daily Consumption

+Peak hourly consumption

25
Q

Principles of Friction loss
1st principle= Length of hose (i think the farther I pull a hose the harder it gets (friction) think first step is pulling hose.
2nd principle = varies on the square 2 the 2 gives it away.

3rd principle = 5th power. it is not exact but I remember a 5 inch hose if 5xs better than a 3 inch hose.

4th principle = for a given velocity friction loss is the same. i relate this to bike racing. on a sprint that i have to overcome the same friction loss the guy next to me does. if I overcome I dont take 4th place.

A

Principles of Pressure pg. 172

1st principle = key is perpendicular. pressure always moves out and away.

2nd principle = key is fluid at rest. hydrostatic.

3rd principle = key pressure increases when confined. if you dont blow of some steam from studying you will pop.

4th principle = depth. I remember feeling in my ears from the bottom of a pool. hurt because of the pressure.

5th. principle = density i remember because it was on the last test and I missed it.

6th principle = shape. water holds no shape so pressure can hold no shape.

26
Q

Which principle of pressure states that the pressure at

the bottom of a vessel is independent of the shape of the

vessel?

A.) First

B.) Sixth

C.) Fourth

D.) Fifth

Pumping and Aerial chapter 5 pg 176

A

B. 6th