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24 Cards in this Set
- Front
- Back
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LP steam boilers must be equipped with a marker indicating the
a) maximum water level line b) low water fuel cut-off line c) lowest permissible water line d) lowest visible water line e) fireline |
C
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A gage glass may be surrounded by a number of thin rods a) when the boiler is a high pressure unit b) to protect the operator from injury c) to prevent cold draft damage d) to protect the glass from damage e) if the glass is attached to a water column |
D
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Quick-closing gage glass valves a) prevent loss of water automatically should glass rupture b) should be installed on all boilers c) will not permit gage glass blowdown d) are designed to prevent operator injury e) require 90 degrees for full travel |
E
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A disadvantage of a gage glass safety-shutoff valve is a) the glass cannot be blown down b) it requires more maintenance c) it cannot withstand high pressure d) loss of water is not prevented e) it makes gage glass replacement more difficult |
B
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Should the steam line or water line to a gage glass become plugged with sludge a) gage glass level will drop in both cases b) gage glass level will drop in the first case and rise in the second c) gage glass level will remain where it was d) the gage glass will read high e) gage glass level will rise in the first case and drop in the second |
D
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Water column supply line crosses will a) permit piping inspection b) allow for piping cleaning and inspection c) replace safety shut-off valves d) be installed only on boilers not under continuous supervision e) prevent gage glass blowout |
B
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Gage glass rupture may be caused by a) maximum allowable boiler pressure b) a cold draft c) a sudden pressure drop d) warming the boiler up too quickly e) improper boiler water treatment |
B
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When gage glass nuts are leaking a) the gage glass should be replaced b) they should be tightened immediately c) new packing should be installed d) the glass should be isolated and depressurized before tightening e) they should be replaced |
D
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When the water connection between boiler and gage glass becomes plugged, the water level in the glass will show a level after a while, that is a) higher than the level in the boiler b) lower than the level in the boiler c) the same as the level in the boiler d) fully filled e) lower than the bottom of the sight glass |
A
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The lowest visible part of the water gauge glass shall be at least __________ mm above the lowest permissible water level recommended by the manufacturer. a) 25 b) 50 c) 75 d) 100 e) 125 |
A
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The ASME code states that each steam boiler shall have one or more water gauge glasses attached either directly to the boiler or to a water column by means of valve fittings not less than __________ mm pipe size. a) 75 b) 51 c) 24 d) 13 e) 10 |
D
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On a multiple steam boiler heating system, a stop valve must be placed at each boiler outlet to a) permit slower system warm-ups b) allow boiler isolation from the system c) prevent steam from entering another boiler d) allow each boiler to supply only a part of the system e) permit different system pressures |
B
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Boiler outlet valves are usually a) gate valves because of their low resistance to flow b) gate valves because of the ability to control flow c) globe valves because of their throttling capability d) globe valves because of their low flow resistance e) installed in tandem |
A
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An outside screw and yoke valve a) is always a gate valve b) readily shows its operating position c) is difficult to lubricate d) requires no packing e) has a non-rising stem |
B
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The quick closing valves on the water gauge requires only a/an __________ of a turn of the valve spindle to change the valve from the full open to the full closed position and vice versa. a) eighth b) quarter c) one-third d) fifth e) half |
B
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The feedwater pipe, before it enters the boiler must be fitted with a __________ valve adjacent to the boiler. a) stop b) gate c) globe d) check e) plug |
D
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A boiler feedwater stop valve a) should never be used to control water level b) is used to isolate the deaerator c) should be a globe valve d) should be located close to the feedwater pump e) is used to isolate the feedwater line |
E
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A globe valve should be used in the feedwater line a) at all times b) whenever it may be used for control purposes c) if it is of the OS&Y type d) when the system is of multiboiler installation e) because of its low flow resistance |
B
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A stop valve is fitted between the boiler and the feed water check valve a) to regulate the feedwater to the water column b) for isolation and to provide a positive shut-off c) if the boiler is a hot water boiler d) if the boiler is gas fired e) to provide feed water regulation to the boiler |
B
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Boiler water foaming may be the result of a) low pH b) excessive blowdown c) low TDS d) high TDS e) dissolved gases |
D
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Boiler blowdown lines have a specific size range based on a) water impurities b) the amount of blowdown required c) boiler capacity d) operating pressure e) line length |
C
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Boiler blowdown piping a) can be reduced in size after the blowdown valves b) must be full size to the point of discharge c) must be at least 51 mm in size d) can have valves of a smaller size than piping e) may discharge to the sewer system |
B
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A steam boiler is blown down in order to a) clean the soot and carbon out of the firebox and tubes b) lower the operating water level in the boiler c) discharge sediment and scale forming matter from the boiler d) test the rated relieving capacity of the safety valves fitted to the boiler e) locate the steam level |
C
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The purpose of the small vent valve or cock located on top of the shell or on top of the water column on most boilers is a) to allow water to escape from the boiler when the boiler is being filled with air b) to allow air in to the boiler when the boiler is being filled with water c) to allow water to escape before the steam stop valve is opened during the warm-up period d) to allow air to escape from the boiler when the boiler is being filled with water e) to allow water into the boiler when the boiler is being drained or cooled preventing the formation of a vacuum |
D
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