High Pressure Boilers Chapter 12

When taking over a shift, the boiler operator must first check the ___.

• steam pressure

• fuel oil supply

• water level on all boilers

• bottom blowdown valves

The low-water fuel cutoff can be tested by blowing down the low-water fuel cutoff or by ___.

• securing the feedwater and allowing the water level in the boiler to drop

• closing the blowdown valves

• modulating the firing rate

• a hydrostatic test

In order to prevent uneven expansion of the boiler on cold startup, the boiler must be ___.

• warmed up as quickly as possible

• thoroughly vented

• heated using steam from outside sources

• warmed up slowly

During startup, the boiler vent should remain open until a pressure of approximately ___ is reached.

• 0.1 psi

• 15 psi

• 50% of the MAWP

• 75% of the MAWP

A safety valve can be manually tested when the ___.

• pressure is at least 25% of the MAWP

• pressure is at least 75% of the MAWP

• burner is going through the firing sequence

• boiler is down for inspection

Boilers equipped with a superheater must be protected during warm-up by ___.

• keeping the superheater drain valve closed until the boiler is cut in on-line

• keeping the superheater drain valve open until the boiler is cut in on-line

• passing the feedwater through the superheater tubes

• bypassing the superheater tubes

Superheaters are prevented from overheated by the circulation of ___.

• air

• steam

• water

• gases of combustion

To ensure high heat transfer rates, ___ should be removed from boiler heating surfaces.

• flue gas

• condensate

• carbon dioxide

• soot

During boiler shutdown, the ___ should be opened when the steam pressure in the boiler has dropped to 10 psi to 15 psi.

• safety valve

• free-blowing drain

• boiler vent

• bottom blowdown valve

As the boiler is cooling down, the boiler operator must maintain ___.

• the NOWL

• the normal draft condition

• the normal feedwater temperature

• a 10% CO2 reading