Flashcards
45 Q
What types of connections are allowed on boilers?
Tapped (threaded) bolted flange or welded (socket or butt) but not victaulic
What are the minimum connections for feed water piping in power boilers?
Less than or equal to 100 sq. ft water heating surface ½ “NPS
Greater than 100 sq. ft water heating surface ¾” NPS
1 Q
What is hanger spacing on 6 inch pipe?
Water -
Gas -
Water — 17
Gas — 21
3Q
What is required when pressure in the discharge pipe can exceed pressure in the inlet pipe?
A check valve in the discharge line
5 Q
Why does each gauge connection need a syphon (pigtail)?
To develop and maintain a water seal that will prevent steam from entering the gauge tube
11 Q
At what size must hangers be designed to permit adjustment while supporting load?
Greater or equal to 2 1/2 inches
48 Q
What is the common length that pipe comes?
22 feet
49 Q
What is the approximate hanger rod size
2” and less — 3/8
2-1/2 and greater — 1/2
50 Q
What is the approximate support spacing for 6 inch NPS for water and for air/steam?
Water — 17 foot
Air/steam — 21 foot
51 Q
Socket weld flanges may be used up to what size?
3 inch NPS 600 lbs
52 Q
When is a journeyman pipefitter license required for anyone installing repairing replacing maintaining or altering any apparatus for piping appliances devices or accessories for heating systems?
What chapter is this listed?
For systems in excess of 700,000 btu per hour
Chapter 146
53 Q
What acceptable method of meeting the requirements for internal inspection and cleaning shall be made for steam and water connections to a water column?
Fitting with a back outlet at each right angle turn
54 Q
What is required when 2 or more traps discharge into the same header?
A stop valve in each discharge line
55 Q
How many pressure gages must a power boiler have and where?
At least one easily readable
35 Q
What is a slow opening valve?
One that requires five 360° turns to fully open or fully close
36 Q
Steam boiler gages shall not be less than how many psi?
30 psi
56 Q
What size must the connection from the boiler to the water column be?
@ least 1”
14 Q
The minimum temperature rating of all valves on a heating boiler shall be at least equal to how many degrees F?
250°F
57 Q
What is the drain for on a gage glass?
To facilitate cleaning
58 Q
When does power boiler code (section l) apply?
- For boilers with gas pressure greater than 15 psig (high pressure)
- For boilers with high temp water with operating pressure greater than 160 psig and temp greater than 250 degrees F
59 Q
The lower edge of the steam connection to a water column shall be?
Not below the highest visible water level in gage glass
60 Q
What is boiler external piping?
Piping that begins at the first weld, thread or flange and includes all piping up to and including the second stop valve
61 Q
What is the service limit for non ferrous pipe or tubes (copper or copper alloys)?
406°F
62 Q
What is the minimum size of the gage connection to the power boiler?
Greater or equal to 1/4 but 1/2” NPS for steal or wrought iron
63 Q
What size is the minimum size of siphon for the pressure gage?
1/4” ID
64 Q
How must the pressure gage be graduated on a power boiler?
To approx. double the pressure of the safety valve but no less than 1.5 times the pressure
65 Q
How can the fuel cutoff be connected to the boiler?
Through tapped openings if nonferrous whys and tees are used
66 Q
What is the boiler proper?
Superheaters economizers and other pressure parts connected directly to the boiler without intervening valves.
67 Q
What are the minimum and maximum sizes for blowoff connections?
Greater than 100 sq ft heating area 1” to 2½” NPS
less than or equal to 100 sq ft heating area ¾ NPS
68 Q
Which is mandatory to have installed on a separate connection on a hot water heating boiler?
Thermometer
69 Q
What section of the code pertains to the construction of power boilers?
Section l
70 Q
What does the feedwater piping for all boilers except high temp water include?
It extends through the required stop valve and check valve.
71 Q
When should flanged or welded inlet connections be used on a safety relief valve?
Over 3” when pressure is greater than 15 PSI
72 Q
What section of the code pertains to the construction of heating boilers?
Section IV
6 Q
When can copper, copper alloys and other nonferrous material be used in dead end and steam or water services?
Up to 406° F connecting lines
What is the hanger spacing on 4” pipe?
Water —
Gas —
Water — 14 feet
Gas — 17 feet
12 Q
What is the maximum temperature for copper or brass or nonferrous pipe/tube?
406°F
25 Q
What cast iron item is not allowed on a high pressure boiler?
Nozzles and flanges
21 Q
The bottom blowdown line of a high pressure water tube boiler is connected to where on the boiler?
Mud drum
19 Q
What is the lowest permissible size of the drain on a gages glass on a power boiler?
1/4” NPS
7 Q
What is a blow down system?
Operates continuously to control concentration of dissolved solids
26 Q
ASME B31.1 power piping code requires that boiler blow off fittings shall be steel & the thickness of pipe & fittings shall not be less than that of schedule 80 pipe when the boiler pressure exceeds what pressure (psig)?
100 psig
22 Q
What section of the code pertains to the construction of pressure vessels?
Section VIII (8)
13 Q
Where can the lowest visible part of the gage glass in a power boiler be located?
Fire Tube (power boilers) @ least 3” above the lowest permissible water level or top row of tubes
Cast iron (heating boilers) 1”
Water tube at least 2”
8 Q
What is a blowoff system?
Operates intermittently to remove accumulation of sediment
27 Q
How shall slip on flanges be attached
Double fillet weld
29 Q
What size boiler does 522 CMR 16 apply to?
Units greater than 200,000 BTU but less than or equal to 700,000 BTU
15 Q
What is the melting point for braze welding
840°F
37 Q
Glass gage connections and pipe connections shall not be less than _______ NPS?
1/2”
38 Q
Why and how is the Hartford loop used?
THE return pipe in a gravity return steam boiler is arranged such that the water cannot be forced out below the safe water level
40 Q
How many safety valves or safety relief valves are required on a power boiler?
At least 1
2 for boilers with greater than 500 sq ft water heating surface
41 Q
What size connection must the drain on a power boiler water column be?
At least 3/4”
41 Q
The upper edge of the water connection to a water column shall be where in relation to the glass gage?
Not be above the lowest visible water level in the glass gage
43 Q
When are steel valves required?
When pressure is greater than 250 psi
44 Q
How should discharge piping be arranged?
As short and straight as possible with no undue stress on valves
46 Q
What must all boilers with a fixed water level have?
At least 1 gage glass
47 Q
Safety valves/relief are not generated to not let the boiler to rise above what percent.
6%
20 Q
When are OS & Y valves used?
- All valves greater than or equal to 2½
NPS at any pressure - All valves greater than or equal to 3-
inch NPS a pressure greater than 600
psi - When boiler steam outlet is over 2” NPS
- Shut off valves between a boiler and a water column
16 Q
When 2 or more boilers are fed from a common source, the piping shall be up to and include?
A globe or regulating valve located between the check valves
28 Q
After field assembly of a cast iron steam heating boiler, you are required to hydrostatically test it. the assembled boiler shall be subjected to a hydrostatic test of not less than what pressure (psig)?
45 (psig)
10 Q
How many sources of feed water are required on power boilers?
2 sources for all boilers greater than 500 sq ft water heating surface area
23 Q
ASME power piping code requires that when the boiler steam outlet is over what size NPS an OS &Y valve shall be used?
2 “
18 Q
When are 2 or more safety valves required?
When the size of the boiler requires a safety relief valve greater than 4 1/2” in diameter
9 Q
What are the limits for copper and brass pipe?
250 psi
406°F
24 Q
The ASME high pressure boiler code limits the use of non ferrous valves.
What is the temperature limitation for a 150 psi class bronze threaded gate
valve?
250° F
17 Q
What are the limits of nonmetallic pipe?
150 psi
& 140° F
30 Q
When 2 boiler stop valves are required on a high pressure boiler, what shall be required?
A blow drain placed between the stop valves
31 Q
All power boiler welding shall be performed in accordance to what code?
Section IX (9)
32 Q
Discuss the provisions for expansion and contraction of steam mains.
Provision anchorage at suitable points so there isn’t undue strain on the boiler
33 Q
Does the boiler external piping include the second stop valve and free blow drain?
Yes
34 Q
Slip on flanges may be used up to what size?
4” NPS
73 Q
Weld certifications and qualifications are covered under what section of the code
Section IX (9)
74 Q
What is the location of cylinder markers on high pressure gas cylinders?
Shoulder
75 Q
Wherever globe valves are used within BEP feedwater piping for either isolation or regulation, the inlet shall be _______?
Under the disk of the valve
76 Q
The simplist hand bending tool is the _______ bender.
Spring
77 Q
In the top and bottom of the acetelyne cylinder are safety plugs designed to melt at _______°F
220°F
78 Q
They type of copper tubing that has the thinnest type of wall is type ______
M
79 Q
Category ________ is the less hazardous service. It includes fluids that are nontoxic, nonflammable and not dangerous to human tissue and are at a pressuer less than 150psi and temperature from -20 degrees F through
186 degrees F.
D fluid service
81 Q
The flame temperature of propylene in oxygen is _________
5250°F
82 Q
The standard oxygen cylinder contains ________
2200 psi
80 Q
The moving part of a valve that directly affects the flow through the valve is
known as the ________.
Disc
39 Q
When installing a low water cut-off on a hot water heating boiler you many install it where?
Any place above the lowest safe permissible water level and before the first stop valve
