Power Engineering MCQ: February 2018

A ) The person who designed the boiler
B ) The ground support of the boiler
C ) The setting of the boiler
D ) The steel work of the boiler
E ) The support beams on top of a boiler

Answer: B

For pressures up to ______ and temperatures up to 454°C, handhole covers with gaskets are used and are bolted into place.

A ) 10,000
B ) 8370
C ) 5000
D ) 6210

Answer: B

When a manhole opening is made in a drum or shell, the area becomes _______ due to the amount of metal removed.

A ) stronger
B ) weaker
C ) flatter
D ) rougher

Answer: B

______ tubes have no welded joints.

A ) Boiler
B ) Superheater
C ) Seamless
D ) Cold

Answer: C

The drum is supported by U-bolts, which permit linear movement of the drum with ___________ variations.

A ) temperature
B ) size
C ) pressure
D ) small

Answer: A

The _____ form the connection for the attachment of the boiler steam generating tubes to the drum and the saturated steam outlet tubes from the top or steam space of the drum.

A ) tubes
B ) welding
C ) stubs
D ) manholes

Answer: C

Why do boilers have allowances for expansion?

1 To prevent the brickwork from cracking
2 To prevent undue stress on the pipework
3 To prevent thermal shock to the steam drum
4 Because the boiler is not always operating at the same temperature

A ) 1, 2, 4
B ) 2, 3, 4
C ) 1, 2
D ) 2, 4
E ) 2, 3

Answer: A

The function of the rolling mill is to ________ the tube and reduce the wall thickness to the approximate dimensions required.

A ) smooth
B ) roll
C ) protect
D ) lengthen

Answer: D

The bottom-supported boiler has concrete drum _________, which support the bottom drum and bottom headers.

A ) hangers
B ) holders
C ) foundations
D ) feet

Answer: C

The steam drum is usually the _______ major pressure component placed in the steel structure.

A ) last
B ) first
C ) second last
D ) only

Answer: B

Drumheads are formed from flat plate by hot pressing with suitable forming dies, and then machining the circumferential welding grooves.

A ) True
B ) False

Answer: A

Nozzles and stubs for connecting the drum to tubes and piping are formed by hot forging from a solid steel cylinder or ______.

A ) billet
B ) stub
C ) pipe
D ) connector

Answer: A

It is not allowed to make any welds directly to the drum _____ stress relieving has been completed.

A ) after
B ) before
C ) during
D ) until

Answer: A

All piping and ductwork must have provision for _______.

A ) expansion
B ) installation
C ) vibration
D ) shrinkage

Answer: A

Cladding (also called lagging) is the metal covering, which protects the _____ surface of the boiler.

A ) inner
B ) outer
C ) wet
D ) bottom

Answer: B

Handholes and manholes are provided in drums and ________ to give access to allow for cleaning, inspection, and repair during the life of the boiler.

A ) furnaces
B ) tubes
C ) headers
D ) superheaters

Answer: C

The boiler pressure parts are allowed to expand __________ from the main supports at the top.

A ) up wards
B ) sideways
C ) downwards
D ) static

Answer: C

Boiler ______ is the term used to describe the airtight metal casing of a boiler wall.

A ) wall
B ) metal
C ) casing
D ) house

Answer: C

Combustion air is fed at three elevations of the furnace: primary, secondary, and ________.

A ) upper
B ) lower
C ) tertiary
D ) after

Answer: C

The combustion products from burning municipal waste are very ________.

A ) hot
B ) corrosive
C ) many
D ) wet

Answer: B

The higher the tube metal temperature, the ________ the degree of tube metal loss.

A ) less
B ) greater
C ) minimum
D ) smaller

Answer: B

The vibration also serves to aid combustion by _______ out the bed of burning biomass.

A ) shaking
B ) leveling
C ) turning
D ) moving

Answer: B

The concept of using waste energy to generate steam has been gaining in popularity. This is mainly because of ______ fuel costs.

A ) lower
B ) moderate
C ) higher
D ) more

Answer: C

Corrosion of the ______ furnace area of the boiler can be severe during refuse firing.

A ) upper
B ) middle
C ) lower
D ) recovery

Answer: C

In order to keep the salts in the boiler water dissolved, and to avoid deposits on the tubes, the steam produced contains _____ moisture.

A ) 30%
B ) 50%
C ) 20%
D ) 10%

Answer: C

If water contacts molten smelt, a violent explosion will result. It is not a _ reaction but a ___ reaction.

A ) chemical, physical
B ) physical, chemical
C ) violent, mild
D ) small, large

Answer: A

The vibrating grate systems, have grate bars attached to a frame that _______ to remove the ash.

A ) rotate
B ) move
C ) vibrate
D ) turn

Answer: C

Steam injection is a procedure for increasing the recovery of oil from wells, which have been _______ depleted.

A ) completely
B ) partially
C ) entirely
D ) almost

Answer: B

Only some of the firetubes in firetube boilers are:

Boiler tubes may be fabricated in a _________ form, or they may be welded.

To form a drum or shell of the required diameter, the plates must be rolled to the correct _________.

Boiler tubes are sometimes welded to _____, which have already been welded to the headers or drum.

Directly after rolling and while the tube is still hot, a reeling machine shown in Fig. 14 smooths the outer surface. This is called __________.

_______ boilers must be built or put together in the field (field erected).

In the field, the stress relieving of welded pipe joints may be accomplished by means of __________ induction coils, which are wrapped around the welded section of the pipe.

The ASME Code Section __ specifies that the size of an elliptical manhole shall not be less than 280 mm by 380 mm or 250 mm by 410 mm.

Postweld heat treatment, often called stressrelieving, consists of heating the welded parts uniformly, to a temperature sufficient to relieve most of the stresses created by the heat from the welding. The parts are then cooled at a constant rate.

Drum manhole openings may be elliptical or _____.

The gaskets used are the woven type for pressures up to _____ kPa and the metallic type for higher pressures.

The drum is used as the major anchor point for other boiler components, and for this reason, accurate location is important.

Coal pulverizers must be installed _____ to allow installation of coal piping to the boiler.

The _________ steel carries the weight of the steam drum and the major pressure components.

Large quantities of ______ are used to complete the foundations, which must support the loads from the boiler and all of the auxiliary equipment.

The covers fit on the ______ of the drum and are held in place by means of bolts and yoke pieces.

The boiler tubes themselves are used to support the top _____ in a bottom-supported boiler.

The use of a membrane or water-cooled walls has reduced the use of __________ in modern water tube boilers.

Tubes for boiler application are either hot-finished, or _____ -drawn depending on the size, tolerance, and finish desired.

Another method used to produce seamless tubes is known as ________.

Nozzles and stubs for connecting the drum to tubes and piping are formed by _____ forging from a solid steel cylinder, or "billet".

Upon completion of the structural steel installation, the "U" shaped hangers are attached to the structural steel for support of the main steam ______.

A final test which is carried out in the manufacturer's shop is a hydraulic or hydrostatic test, (conducted according to the ASME Code Section I, PW-54), at a pressure of ____ times the design pressure.

What is meant by the foundation of a boiler?