Part b unit 4

Your answer is correct Which of the following is NOT a way to maintain a positive pressure on a boiler during a wet layup? use a nitrogen blanket. use a head tank. use a steam blanket. use an oxygen scavenger.

use an oxygen scavenger.

The safety valve of a steam heating boiler pops open at 100 kPa. Which of the following is a code-acceptable re-seating pressure? 98 kPa 65 kPa 80 kPa 50 kPa

80 kPa

The most important rule in safe operation of steam boilers is to: keep the heat transfer surfaces clean. maintain the boiler room log try to keep make-up water to a minimum. keep water in the boiler at the proper level.

keep water in the boiler at the proper level.

In the event of a power failure, which of the following will likely require a manual restart when power is restored? small condensate return pumps large air compressors unit heater fans air dryers

large air compressors

Because natural gas is colourless and odourless, ___________ is added to the gas so that it is easier to detect a leak. fluorescent dye propane an irritant mercaptan

mercaptan

When locking out a cooled down steam boiler closethe water column and gauge glassvalves, and lock them. closethe non-return valve drain, and lock it. open the drum vent, and lock or tag it. open the continuous blowdown valve and tag it.

open the drum vent, and lock or tag it.

Water hammer can be caused by operators: opening valves too slowly. opening valves too quickly. starting a pump with the discharge valve closed. draining condensate prior to heating up steam lines.

opening valves too quickly.

How often should the low water cut-off of a low pressure steam heating boiler be blown off? Daily Monthly Twice per shift Weekly

Daily

One way to keep oxygen out of the boiler water system is to: Increase the continuous blowdown to remove water with high dissolved oxygen concentration. Keep make-up water to a minimum. Keep the drum vent closed when the boiler is not in operation. Control the boiler water pH.

Keep make-up water to a minimum.

A boiler pressure explosion: Could be the result of water in the fuel oil Could be the result of inadequate ignition May be caused by a low water condition Could result from a defective flame scanner

May be caused by a low water condition

A high water level in a boiler: Will cause the high water cut-off to shut down the boiler Is usually caused by a boiler feed pump malfunction Will necessitate an immediate shutdown and cool down May cause water carryover into the header

May cause water carryover into the header

How should the operating limit pressure control switch on a steam boiler be tested? Jumper the contacts and observe when the boiler shuts off Remove the control from the boiler and test with a pressure source and a master pressure gauge. Observe that the boiler cuts in and cuts out during routine boiler operation. Install a new control annually, because the operating limit cannot be easily tested.

Observe that the boiler cuts in and cuts out during routine boiler operation.

Which of the following is NOT done prior to start up of a boiler? Check the fuel supply Fill the boiler with water Open the blowoff valve Check for a valid operating certificate

Open the blowoff valve

Although boilers have many different ignition systems, they all follow the same sequence of steps. Which of the following is the first step? Pre-purge Pilot ignition Main burner ignition Run period

Pre-purge

When cooling down a steam boiler that has been taken out of service, a vent valve on a steam drum should be opened to: Prevent a vacuum from forming in the boiler Release air from the boiler Allow for the increase of the water content as steam condenses Let the operator know when the steaming has ended

Prevent a vacuum from forming in the boiler

Which is the first step when starting a boiler's fuel oil system? Check the pressure drop across the fuel filter. Reset the low oil pressure cut-off switch. Check for leaks. Start the fuel pump.

Start the fuel pump.

Prior to shutting down a hot water boiler for an extended shutdown: Test all operating and limit controls. Raise the pressure to test the safety relief valve. Start draining the boiler slowly. Shut the boiler off when firing on high by closing the main test firing valve.

Test all operating and limit controls.

Furnace explosions may be caused by: Inoperative low water fuel cut-offs The accumulation of fuel-air mixture in the furnace Scale accumulations on the boiler surfaces Excessive furnace purging

The accumulation of fuel-air mixture in the furnace

Furnace explosions occur when the boiler is being over-fired. a pressure part of the boiler, such as the shell, a watertube, or a firetube, bursts. an accumulation of combustible gases ignites and explodes within the furnace. excessive internal pressure or structural weakening has occurred.

an accumulation of combustible gases ignites and explodes within the furnace.

A typical natural gas flame should be bright yellow, with orange tips. bright yellow, with black tips. asymmetrical, and as close as possible to the heat transfer surfaces. blue, with orange at the tip of the flame

blue, with orange at the tip of the flame

New boilers require a _____________ and a _____________ dry-out before entering operation. boil-out, refractory certificate, complete refractory curing, waterside mechanical cleaning, fireside

boil-out, refractory

A well-planned PM system will respond quickly to equipment breakdown. ensure equipment longevity. create less need for rounds and inspections. will cover only the most critical plant equipment.

ensure equipment longevity.

When a power failure occurs, control valves go to a fail-safe position. fail open. fail shut. fail last.

go to a fail-safe position.

Rising stack temperatures, at a given firing rate, indicate Correct burner operation A defective stack thermometer Boiler corrosion heat transfer surfaces are becoming dirty.

heat transfer surfaces are becoming dirty.

When warming up a steam boiler, open the boiler drum vent to prevent over-pressurization of the boiler during start-up. permit the release of corrosive dissolved gases, such as oxygen and carbon dioxide, from the boiler water. ensure a flow of steam through the superheater banks. keep a vacuum from forming in the drum, if the burner trips off.

permit the release of corrosive dissolved gases, such as oxygen and carbon dioxide, from the boiler water.

What is usually considered the first task when coming onto a shift: Check water levels complete the water tests perform a complete set of operator rounds read the log book

read the log book

Mechanical chart recorders require regular replacement of paper and ink. need their charts replaced each month. require constant winding of their clock mechanisms. are used so regular readings do not need to be taken.

require regular replacement of paper and ink.

Standby equipment: should never run unless required. need annual run tests, witnessed by anauthorized inspector. should be run on a regular basis. require little or no maintenance.

should be run on a regular basis.

If the main burner goes out when warming up a cold boiler, the operator should immediately: turn off the boiler, purge the furnace, and restart the burner shut down the boiler, close the main and pilot test firing valves, and determine the cause of the trouble. re-light the burner to see if it goes out again. report the flame failure to the Chief Engineer.

shut down the boiler, close the main and pilot test firing valves, and determine the cause of the trouble.

Boilers should be warmed up with maximum combustion air, to prevent smoking rapidly, so the metal heats up faster slowly, to minimize differential expansion and thermal shock using only the pilot burner.

slowly, to minimize differential expansion and thermal shock

To prevent water hammer and the severe damage it causes, it is imperative that steam traps are isolated during warm up. boilers are warmed slowly. steam lines and headers are warmed up before admitting steam to the steam lines. steam lines and headers are isolated before boilers are started.

steam lines and headers are warmed up before admitting steam to the steam lines.

In many plants, the standby boiler feedwater pump starts automatically when the on-line pump fails to provide adequate feedwater pressure. the water level reaches the lowest permissible water level. a low water alarm occurs. the feedwater control valve opens greater than 95%.

the on-line pump fails to provide adequate feedwater pressure.

New refractory in a boiler must be thoroughly dried on low fire because high fire uses too much fuel. by operating only the pilot burner. for no longer than one hour. to dry the refractory slowly and keep it from cracking.

to dry the refractory slowly and keep it from cracking.

When warming up a boiler, it should be: warmed up quickly so there is not enough time for differential thermal expansion to occur warmed up quickly to prevent flue gas condensation warmed up at a rate of one degree every five minutes, to protect the refractory warmed up at 55 degrees Celsius per hour, to prevent thermal shock

warmed up at 55 degrees Celsius per hour, to prevent thermal shock

ASME VII states that a high-pressure steam plant comprised of a single power boiler may have its boiler and steam lines warmed-up at the same time, or independent of each other. interconnected with two other boilers. drained by the same steam trap. made of cast iron.

warmed-up at the same time, or independent of each other.

What is the recommended test frequency for flame safeguard devices? every shift daily weekly annually

weekly