2Nd Class Fireman, High Pressure Boilers, Chapter 5, Exam Q&a

Front 1

What does a makeup control valve do?____

Back 1

Maintain a constant water level in the feedwater heater

Front 2

The ____ is the water level designated as being the proper water level for safe boiler operation

Back 2

Normal Operating Water Level (NOWL)

Front 3

The purpose of a feedwater Regulator is to ____

Back 3

Maintain a constant water level in the boiler

Front 4

Feedwater regulators control the feedwater pump to maintain the water level ____

Back 4

at the NOWL

Front 5

The sequence of three numbers found on the nameplate mounted on a reciprocating feedwater pump refers to the ____

Back 5

Diameter of the steam piston, diameter of the water piston, and length of the pump stroke

Front 6

____ are usually used to create the draft needed to overcome the resistance caused by economizer tubes

Back 6

Induced draft fans (and sometimes a balanced draft system)

Front 7

An economizer uses the heat energy from the gases of combustion leaving the boiler to heat the ____

Back 7

Feedwater

Front 8

What type of pump is a Turbine feedwater pump? ____

Back 8

Positive-displacement pumps

Front 9

A turbine feedwater pump must be equipped with a(n) ____ on the discharge line to protect the pump from excessive pressure

Back 9

Relief Valve

Front 10

Water that is too hot in the open feedwater heater can cause ____

Back 10

The feedwater pump to become steambound

Front 11

Water temperatures that are too low in an open feedwater heater will cause ____

Back 11

Oxygen pitting in the boiler

Front 12

The ____ of a centrifugal feedwater pump is the rotating element that imparts centrifugal force to the liquid

Back 12

Impeller

Front 13

Plant efficiency is increased when a(n) ____ uses steam that is bled or extracted from a steam turbine

Back 13

Economizer

Front 14

If only one low-water fuel cutoff is used, it must have a(n) ____

Back 14

Manual Reset

Front 15

One way to increase the efficiency of a plant in relation to fuel is to _____

Back 15

Recover as much heat as possible from the fuel

Front 16

A ____ is a boiler fitting that reduces the turbulence of boiler water to make it easier to measure the water level

Back 16

Water column

Front 17

The piping that connects a water column to the boiler must be a minimum of ____ “ and must meet the ASME code requirements for pressure and temperature

Back 17

1

Front 18

____ is the process where the water level in a boiler momentarily rises with an increase in steam demand

Back 18

Swell

Front 19

____ feedwater regulators are found on package firetube or watertube boilers where feedwater pumps run either intermittently or continuously

Back 19

Float

Front 20

A three-element feedwater regulator measures the steam flow from the boiler, the ____ into the boiler, and the water level

Back 20

Feedwater Flow

Front 21

After blowing down a thermohydraulic feedwater regulator, approximately 60 min should be allowed for the regulator to ____ before being returned to service

Back 21

Stabilize

Front 22

A(n) ____ is used in applications where there are varying flows of condensate and additional condensate storage capacity is required

Back 22

Surge Tank

Front 23

The ____ pump uses the shape of its casing to direct the discharge

Back 23

Centrifugal

Front 24

Some boiler rooms use ____ pumps for reserve or back-up units in the event of an electrical power failure

Back 24

Reciprocating

Front 25

A(n) ____ feedwater heater allows steam and feedwater to mix with each other at atmospheric pressure to raise the temperature of the water

Back 25

Open

Front 26

The primary function of a low-water fuel cutoff is to ____ the burner limit circuit and shut down the burner

Back 26

Deenergize

Front 27

The water column is connected to the ____ and to the water side of the boiler

Back 27

Top of the steam space

Front 28

____ gauge glasses are used at pressures up to about 300 psi, depending on the type and thickness of the glass material

Back 28

Tubular

Front 29

For every 10 degree Fahrenheit rise in feedwater temperature, there is a ____ % fuel savings

Back 29

1

Front 30

A(n) ____ is a shell-and-tube feedwater heater used to capture heat from continuous blowdown water from a boiler or flash steam from a process

Back 30

Closed Feedwater Heater

Front 31

ASME code states that boilers having over ____ sq ft of boiler heating surface must have at least two means of supplying feedwater to the boiler

Back 31

500

Front 32

The ____ is the rotating element in a centrifugal pump that imparts centrifugal force to the liquid

Back 32

Impeller

Front 33

A ____ feedwater pump is a rotary positive-displacement pump that uses a flat impeller to discharge feedwater into the boiler

Back 33

Turbine

Front 34

Most pump manufacturers do not recommend operating a variable-speed feedwater pump below approximately 40 ____

Back 34

Hz (hertz)

Front 35

When two or more boilers are fed from a common feedwater source, a gate valve is installed on each ____ between the check valve and the main line

Back 35

Branch line

Front 36

For boilers with a MAWP above 400 psi one of these is needed:

Back 36

- two gauge glasses that are in continuous service and visible to the operator

- two remote water level indication systems independent of each other that are continuously displayed, along with a single gauge glass, which may be isolated from continuous operation but must be maintained in an operable condition.

- one independent remote water level indication system and one gauge glass, both of which must be in continuous operation at all times.

Front 37

How often do you blow a water column down?

Back 37

Once a shift and when you’re not sure if the water level is correct.

Front 38

How fast should valves be opened and closed?

Back 38

Slowly

Front 39

What happens if you close a valve too fast?

Back 39

Can cause a drastic increase in steam pressure and raise water level.

Front 40

A 10 degree Fahrenheit rise in feedwater temperature there is how much savings in fuel?

Back 40

1% savings in fuel.

Front 41

ASME CSD-1 requires all steam boilers to have at least _____ low-water fuel cutoff(s) even though the boiler may be equipped with an automatic makeup water feeder.

Back 41

One

Front 42

A _____ pump uses the shape of its casing to direct the discharge.

Back 42

Centrifugal

Front 43

Feedwater heaters can improve water quality because ______ in warm feedwater.

Back 43

Oxygen dissolves

Front 44

A low-water fuel cutoff is a boiler control that secures the ___ in the event of a low-water condition.

Back 44

Burner.

Front 45

The low-water fuel cutoff is located ___.

Back 45

Slightly below the NOWL.

Front 46

The low-water fuel cutoff is located ___.

Back 46

Slightly below the NOWL.

Front 47

If only one low-water fuel cutoff is used, it must have ___.

Back 47

A manual reset.

Front 48

A ___-type low-water fuel cutoff consists of a cylindrical object that is immersed in the water and connected to a spring or torsion device that twists in response to the weight of the cylinder.

Back 48

Displacer.

Front 49

An evaporation test needs to be performed on a low-water fuel cutoff at least every ___.

Back 49

30 days.

Front 50

On firetube boilers, the ___ is located so that the lowest visible part of the gauge glass is 2′′ to 3′′ above the top of the tubes.

Back 50

Water column.

Front 51

For boilers with an MAWP up to ___ psi, the minimum ASME Code requirement for gauge glasses is to use at least one gauge glass that is in service at all times.

Back 51

400.

Front 52

___ are valves located on the water column of a boiler that are used to determine the boiler water level if the gauge glass is not functioning.

Back 52

Try cocks.

Front 53

The water column and gauge glass should be blown down ___ or whenever the operator is in doubt as to the true water level.

Back 53

Once every shift.

Front 54

Some flat glasses have ___ between the glass and steam or water to prevent the steam or water from coming into direct contact with the glass.

Back 54

Mica.

Front 55

___ is a process where the water level in a boiler momentarily rises with an increase in steam demand.

Back 55

Swell.

Front 56

A ___ remove sludge and sediment from a float chamber.

Back 56

Blowdown line and valve.

Front 57

Float feedwater regulators should be opened once every ___ for cleaning and inspection.

Back 57

Year.

Front 58

___ are used to isolate steam and water to the generator.

Back 58

Stop valves.

Front 59

A ___ feedwater regulator is typically used with power boilers that generate electricity.

Back 59

Three-element.

Front 60

For every 10°F rise in feedwater temperature, there is a ___% fuel savings.

Back 60

1%.

Front 61

A(n) ___ is a feedwater heater that operates under pressure and is used to separate oxygen and other gases from steam before releasing the gases to the atmosphere through a vent.

Back 61

Deaerator.

Front 62

An open feedwater heater is located ___.

Back 62

Above the feedwater pumps.

Front 63

Economizers are used to ___.

Back 63

Reclaim heat from the hot gases of combustion and heat the feedwater.

Front 64

A(n) ___ is used to divert the acidic condensate to a drain in a condensing economizer.

Back 64

Baffle.

Front 65

The ASME Code states that boilers having over ___ sq ft of boiler heating surface must have at least two means of supplying feedwater to the boiler.

Back 65

500.

Front 66

A(n) ___ is the rotating element that imparts centrifugal force to a liquid.

Back 66

Impeller.

Front 67

Turbine pumps must be equipped with a ___ on the discharge line to protect the pump from excessive pressure.

Back 67

Relief valve.

Front 68

A(n) ___ is a motor controller used to vary the frequency of the electrical signal supplied to an AC motor in order to control its rotational speed.

Back 68

Variable speed drive.

Front 69

A typical application for ___ in boiler feedwater pumps and deaerator systems includes continuously running centrifugal pump applications where the motor horsepower is 15 HP and greater.

Back 69

Variable speed drive.

Front 70

A ___ valve is the valve closest to a boiler.

Back 70

Stop.

Front 71

Why is feedwater heated?

Back 71

Efficiency, there is a 1% savings in fuel per 10 degree Fahrenheit rise in feedwater.

Front 72

What is the difference between a reciprocating pump and a centrifugal pump?

Back 72

A reciprocating pump is a positive displacement pump which is forced by a piston. It does not discharge fluid continuously. It is more efficient than a centrifugal pump. A centrifugal pump uses centrifugal force of a rotating element to continuously pump fluid.

Front 73

How do you know when a centrifugal pump is full?

Back 73

Water will start spraying out.

Front 74

What is pump cavitation and how do you control it?

Back 74

Caused by heated water bubbles and can cause a pump to fail. You control this by keeping the pump full. Make sure the suction and discharge sides are okay.