Boiler Operation and Maintenance Quiz3

The steam injector lifts the water but fails to force it into the boiler. The trouble may not be due to:

• Dry Steam

• Insufficient Steam Pressure

• Leak in the water pipe

• All of the above

The pH value of water in steel tube economizers should be:

• 5-6

• 8-9

• 10-12

• 13-14

The best suited coal for chain or travelling grate stoker boiler is:

• Caking coal

• None Caking coal

• Pulverized coal

• High Sulphur coal

Which material is used in construction of convective and radiant super-heaters?

• High Alloys Cr-Ni Austenitic class steel

• Aluminium Alloys

• Cast Iron

• Any Steel

A packaged boiler is one in which various parts like firing equipments,fans, feed pumps and automatic controls are:

• Supplied by same manufacturer in loose and assembled at site

• Supplied mounted on a single base

• Purchased from several parties and packed together at site

• Does not exist

Which is not correct statement about the effect of sulphur in fuel?

• It has heating value

• It helps in electrostatic precipitation of ash in the flue gases

• It leads to corrosion of air heater and ducting etc. if flue gas exit temp is low

• All of the above

Device used to put off fire in the furnace of boiler when water level falls to unsafe limit:

• Safety Valve

• Fusible Plug

• Stop Valve

• Blow off cock

What is the height of nozzles above the base plate?

• 50-100mm

• 130-155mm

• 110-125mm

• None of the above

The maximum discharge through a chimney occurs when the chimney height is:

• Infinite long

• Equal to height of hot gas column producing draft

• Outside temp is very low

• More than the tallest building nearby

In a three-element control system, feed water control system uses:

• Fuel flow, steam pressure and temperature

• Loop correcting feed flow to drum level

• Feed water flow, steam flow and drum level

• None of the above