4Th Class Power Engineering Chapter 52

What is a major disadvantage of a firebox boiler?

A. First cost is relatively high

B. Cleaning and inspection can be difficult.

C. It is not very compact

D. It has a low heat transfer efficiency

For what use was the wet back Scotch boiler primarily designed for?

A. A very high capacity electric generation

B. Marine service

C. Building heating service

D. Railway service

What boiler type is built ready for installation?

A. Locomotive boiler

B. Scotch marine boiler

C. HRT boiler

D. Packaged boiler

A hot water heating boiler may not exceed _______ kPa operating, nor a water temperature of _______°C.

A. 15, 80

B. 50, 100

C. 80, 200

D. 103, 121

List the limiting factors used to classify hot water supply boilers.

A.

B.

C.

The forerunner of the modern packaged firetube boiler was the:

A) Horizontal return tubular boiler

B) Sterling boiler

C) Scotch Marine boiler

D) Firebox boiler

E) Locomotive boiler

One of the earliest firetube boilers was the:

A) Locomotive boiler

B) Haycock boiler

C) Marine boiler

D) HRT boiler

E) Firebox boiler

A firetube boiler commonly used for hot water heating systems in residences and small apartments is the:

A) Tubular unit

B) Scotch firetube packaged unit

C) HRT unit

D) Steel plate vertical unit

E) Firebox unit

The firebox boiler is a _____ pass firetube boiler:

A) Two

B) Horizontal

C) Single

D) Three

E) Vertical

A boiler that utilised a water leg and was primarily used for heating purposes was the:

A) Firebox boiler

B) HRT boiler

C) Marine boiler

D) Scotch boiler

E) Locomotive boiler

The fire line in a firetube boiler:

A) Will be 76 mm above the bottom most part of the gage glass

B) Will be the end of the flame in the furnace

C) Is the end of the furnace tube

D) Will be 53 cm above the lowest permissible water level

E) Will be the highest part of the heating surface

The corrugated furnace was used in the:

A) Locomotive Type Boiler

B) Watertube Boiler

C) Scotch Boiler

D) Firebox Boiler

E) Horizontal Return Tubular Boiler

Smaller firetube boilers are low cost and:

A) Have simple rugged construction

B) Do not cause much damage on waterside rupture

C) Require very critical water treatment

D) Reach operating pressures very quickly from cold start

E) Are not very suitable for on-off operation

Which of the following boilers is considered a single pass boiler?

1. HRT boiler

2. Scotch marine boiler

3. Packaged firetube boiler

4. Vertical firetube boiler

5. Steel plate heating boiler

A) 1, 2

B) 4, 5

C) 1, 3

D) 2, 5

E) 1, 4

A hot water boiler falls under ASME Section IV when its:

A) Temperature is greater than 120ºC

B) Both a and c

C) Temperature is less than 120ºC

D) Pressure is less than 1 100 kPa

E) Pressure is greater than 1 100 kPa

The disadvantages of the HRT boiler include:

1. Ease of cleaning

2. Limited steaming and operating pressure

3. High cost of brickwork setting

4. Low cost

5. Adequate foundation is required

6. Large water capacity

A) 2, 3, 4

B) 3, 4, 5

C) 1, 2, 3

D) 2, 3, 5

E) 4, 5, 6

A component used to increase the volume of the steam space in a locomotive boiler was the:

A) Crown sheet

B) Dry pipe

C) Steam leg

D) Shell head

E) Steam dome

A device used to prevent the carry over of moisture with the steam of a scotch marine boiler is the:

A) Nozzle

B) Crown tube

C) Head pipe

D) Dry pipe

E) Internal pipe

A steel plate vertical firetube unit is divided into two sections and the upper part is often called the:

A) Flue gas collector section

B) Reversing section

C) Expansion tank

D) Furnace

E) Heat exchanger

Which of the following is not true about steel plate heating boilers?

A) The combustor is located in the lower part

B) The upper section of the boiler is filled with water

C) They use a circulating pump to force water from radiators into the boiler

D) They use normal tubes to allow the combustion gases to flow through the boiler

E) They use firetubes with thin steel strips installed on the inside of the tubes

Initially, the firetube boiler was not up to manufacturing expectations because:

A) Too many equipment suppliers were involved in its manufacture

B) Tradesman were not licensed and properly qualified

C) The unit was constructed at the factory

D) There were no legislative standards set

E) Boiler plate was inferior

In order to maintain gas velocity throughout all boiler gas passes, a firetube boiler has:

A) Fewer tubes in each pass and increasing in diameter with each pass

B) The same number of tubes in each pass when both an FD and ID fan are used

C) Fewer tubes in each pass so that tubes of the same size can be used

D) The same number of tubes in each pass with a gas bypass around the first two passes to induce flow

E) The same number of tubes in each pass but decreasing in diameter with each pass

One of the advantages of the firetube boiler over the watertube and tubular boiler is in the:

A) Operation safety area

B) Water consumption area

C) Fuel and combustion area

D) Electricity consumption area

E) Water treatment area

In a packaged firetube boiler, the flue gas velocity within the unit is maintained by:

A) Decreasing forced draft fan speed

B) Increasing forced draft fan speed

C) Constructing a taller stack

D) Varying the firetube diameters

E) Varying the number of firetubes

Packaged firetube boilers:

A) Are not very rugged relative to portability

B) Require special foundations or footings

C) Have very specific design pressures to meet customer needs

D) Have maintenance access difficulties

E) Require relatively small building volumes