問題一覧
1
_____ is exertion of equal forces and opposite direction.
Shear
2
______ Is the ability of a material to return to its original shape after being deformed.
Resiliency
3
_______ Is the ability of a material to bend without cracking.
Malleability
4
_______ Is the ability of a material to withstand pressure before cracking.
Tensile Strength
5
Changing a controlled device to a degree that is proportional to the need is called______.
Modulation
6
What provides circulation to the waterfall tubes?
Down comers tubes
7
What is the last valve to be closed before lighting of?
Economizer vent
8
They say bolt this viscometer is used for_____.
Testing and grading of oil.
9
To prevent caking and drying coat entering the pulverizer______.
Warm air is used
10
_______ result in high carbon dioxide reading in gases of combustion.
Complete combustion
11
______ Air supply to the furnace to control the rate of combustion.
Primary air
12
______ Air supply to the furnace to control combustion efficiency?
Secondary air
13
_______ air supply to the furnace when you complete combustion?
Excess air
14
______ results in a high O2 reading?
Incomplete combustion
15
_______ is a control in which flow of fuel and air or precisely measured so it is always correctly proportion.
Metering control
16
Define cogeneration boiler system?
Is the process of generating electricity then using the leftover heat from the generation process for heating buildings
17
Define combined-cycle boiler system?
Is an electric powered generating system that uses both a gas-turbine generator and a steam-turbine driven generator.
18
The telltale of a stay bolt is usually_____in diameter?
3/16”
19
Hand holes are typically about_____ in size
4”x5”
20
1 sq ft equal how many sq inch’s?
144 sq in
21
1 cu ft equals how many cu inches?
1728 cu in
22
What is the difference between the safety valve and a relief valve?
Safety valve pops open and reseats when there is measured pressure drop, while relief valve opens in proportion to the excess pressure.
23
What is blowdown of a safety valve?
Is the amount of pressure that must be reduced before a safety valve will reseat
24
What happens to the pressure of the discharge side of a centrifugal pump if the pressure from the suction side increases?
Increase in pressure
25
What prevents leakage around a pump shaft?
Packing
26
What is a lantern ring?
Is a spacer installed in between two rings of packing
27
How do you adjust packing?
Tighten one half of a flat on each packing nut at a time alternating from side to side until the leak stops.
28
How do you adjust a mechanical seal?
There is no adjustment on a mechanical seal
29
Should a centrifugal pump be started with the discharge valve open or closed?
Closed
30
What is cavitation of a pump?
Is when water flashes into steam as it enters the impeller.
31
What is desired PH of boiler water?
10.5-11.5
32
What is a turn down ratio of a modulating burner?
Is the ratio between the maximum firing rate and the minimum firing rate of a burner
33
A low water cut-off usually placed on the boiler from_____to _____ below the NOWL.
2 “ to 6”
34
An______ is 1/1000 of an ampere.
Milliamp
35
A_____is an audible alarm that is created electrically or electronically.
Annuciator
36
A_______ is an instrument used to send information about the condition of a process to a control device.
Transmitter
37
Water column are made of?
Cast iron, ductile iron, steel
38
The slip of a pump typically ranges from_____% to______%
5%-10%
39
A______is a chemical that prevent corrosion in condensate and steam pipings.
Anime
40
A______is the burning of a fuel with precisely the amount of air required so that no unburned fuel or unused oxygen remains.
Stoichiometric Combustion
41
What stamp is put on safety valve after repair?
VR
42
After blowing down the boiler, the gauge glass slowly returning to normal is an indication of what?
Bottom gauge glass is clogged
43
What refrigerant classification is ammonia?
Type B2
44
What type of control operates from steam pressure?
On/Off
45
Which LWCO does not use mercury switch?
Electronic probe
46
What are the pressure control on a steam boiler?
Operating pressure cut-out & upper limit control
47
What are the temp control on a Hot Water boiler?
Operating limit control and upper limit control
48
What is hard forming scale?
Silica
49
Which chemicals is used to combat scale?
Combined phosphate treatment
50
What chemical other then sulfite is used to combat corrosion in Boilers?
Hydrazine
51
What will neutralize acid?
Alkali and lime soda
52
Describe three types of the dearator:
Tray Dearator= Causes water to cascade downward in a zigzag pattern and over small staggered trays. Spray Dearator= Uses self adjusting spray nozzles in the top section to break the water flow into a spray of small water droplets. Combination Tray-Spray Dearator= Uses spray and spray nozzle to break the water flow into a small droplets.