Homework

Question 1

Charles second law

Answer 1

For a constant volume process, pressure increases as temp increases

Question 2

Saturated steam

Answer 2

Temp corresponds with pressure

Question 3

Superheated steam

Answer 3

Temp above corresponding pressure

Question 4

Charles first law

Answer 4

For a constant pressure process, volume increases as temp increases

Question 5

Boyles law

Answer 5

Constant temp process, change in pressure causes opposite change in volume

Question 6

Solid and hollow Staybolts

Answer 6

Hold inner and outer wrapper sheets together. 3/16” telltale hole

Question 7

Girder stay

Answer 7

Used on crown sheet of scotch marine

Question 8

Radial stay

Answer 8

Superseded girder stay, more flexible and hold less scale.

Question 9

Diagonal stay

Answer 9

Above tubes to stay flat portions of heads not supported by tubes

Question 10

Caustic embrittlement

Answer 10

High alkaline material leads to breakdown and weakening of boiler metal

Question 11

Dog stay

Answer 11

Used on man and hand holes

Question 12

Solid through stays

Answer 12

Holds rear and front tube sheets. Nuts on inside and outside of boiler drum

Question 13

Float feedwater regulator

Answer 13

Float operates off water level and moves a mercury switch

Question 14

Bhp

Answer 14

33475 btus

Question 15

One vertical foot water column

Answer 15

.433

Question 16

Water column pipe requirements

Answer 16

Minimum 1” pipe. 3/4” blowdown.
0-250F cast iron
251-350 malleable iron
351+ steel

Question 17

Thermodynamic steam trap

Answer 17

Single moving disk. Steam pushes disk down to close discharge and condensate pushes disk up to open.

Question 18

Blowdown pipe requirements

Answer 18

1” minimum 2.5” max.

Boilers over 100psi require two

Question 19

How many turns to open slow opening valve

Answer 19

5

Question 20

Carryover

Answer 20

Small amount of water enters header

Question 21

Priming

Answer 21

Large amount of water enters header

Question 22

Hp

Answer 22

33000 ftlbs/min

Question 23

Float thermostatic steam trap

Answer 23

Ball and float. Rises with condensate level. Thermostatic element opens air vent

Question 24

Inverted bucket steam trap

Answer 24

Steam flows into an inverted bucket and holds bucket up and closes discharge. When condenses bucket falls and opens discharge.

Question 25

Blowdown or blowback

Answer 25

Drop in pressure that closes safety valve. Normally 2 to 8 lbs below popping pressure but not more than 4%

Question 26

When are extra heavy blowdown pipes needed?

Answer 26

Above 125psi

Question 27

Safety valve pipe requirements

Answer 27

3/4" minimum and 4 1/2" max pipe size

Question 28

Impulse steam trap

Answer 28

Works on pressure differential

Question 29

Thermostatic steam trap

Answer 29

Bellows filled with fluid that expands and contracts

Question 30

Safety valve relieving capability

Answer 30

Must relieve enough pressure to allow boiler to not exceed 6% of the mawp

Question 31

Hydrostatic test

Answer 31

Pressure brought up to 1.5 times the mawp. Water temp at least 70F

Question 32

Thermoexpansion feedwater regulator

Answer 32

Thermostat attached to mechanical linkage.

Question 33

Thermohydraulic feedwater regulator

Answer 33

Tube within a tube. Inner tube connected to water and steam side of boiler. Outer tube filled with distiller water and connected to bellows and valve.

Question 34

MAWP=

Answer 34

Tensile strength x metal thickness x joint eff. / safety factor x radius of drum in inches

Question 35

Two or more safety valves needed if

Answer 35

Over 500 sqft heating surface equipped with superheaters one is not of sufficient capacity or if mawp is lowered by inspector

Question 36

1 gallon of water=lbs

Answer 36

8.33 lbs

Question 37

1 gallon = cubic inches

Answer 37

231

Question 38

A therm =

Answer 38

100,000 btu

Question 39

Matt

Answer 39

Mixture atomization temp time. All needed for complete combustion

Question 40

Gpms of recip pump

Answer 40

Lane/231

Question 41

Bituminous coal

Answer 41

Soft coal high volatile matter

Question 42

Pressure atomizing burner

Answer 42

Fuel oil burner atomizes fuel without using steam or air. Uses mechanical. Tip and plate.

Question 43

Sulfur dioxide

Answer 43

Byproduct of high sulfur content coal.

Question 44

Specific gravity

Answer 44

Ratio of any volume of fuel oil @ 60F to the weight of any equal volume of water @ 60F. Measured by a hydrometer.

Question 45

Stoker

Answer 45

Mechanical coal feeder

Question 46

Ultimate analysis

Answer 46

NOCASH

Question 47

Pressure reducing governor

Answer 47

Low pressure gas systems. Reduces to 0lbs

Question 48

Carbon dioxide

Answer 48

Co2. Not so bad. What plants breath. Byproduct of complete combustion

Question 49

Carbon monoxide

Answer 49

Co. Byproduct of incomplete combustion. Very bad. Not all fuel burned

Question 50

Steam atomizing burner

Answer 50

Uses steam at a pressure above 20psi or higher to atomize fuel

Question 51

1" mecury = psi

Answer 51

.491

Question 52

Anthracite coal

Answer 52

Hard coal very high carbon content