72.

73.

74.

75.

76.

77.

78.

79.

The boiler draught is

(A) The flow of adequate supply of steam

(B) The difference of pressure is maintained above and below the fire grate
(C) The flow of adequate quantity of water in the boiler

(D) The pressure maintained in the chimney

The factor of evaporation of boiler is
(A) Unity (B) Less than unity
(C) Zero (D) Greater than unity

When the enthalpy of steam is h KJ/Kg and the enthalpy of feed water is hf,KJ/Kg then
the factor of evaporation is given by

(A) h — hf,/2257 (8) h + hf,/2257

(€) ൨. hf,/2257 (೧) h/ hf,x 2257

The performance of a steam boiler is measured in terms of its

(A) Feed water temperature (B) Working pressure
(C) Fuel (D) Evaporative capacity

Heat balance sheet of a steam boiler shows

(A) Overall efficiency of the boiler

(B) Percentage of available heat utilised

(C) Complete account of heat supplied by 1 Kg of dry fuel and heat consumed
(D) Thermal efficiency of the boiler

The main objectives of a boiler trial are:

(A) To determine the feed water temperature

(B) To determine the generating capacity of the boiler
(C) To determining the overall efficiency of the boiler

(D) To determining the temperature of steam produced

Boiler efficiency does not depend on
(A) Calorific value of fuel used (B) Specific heat of steam generated

(C) Boiler design (D) Operating time

The evaporative capacity of a steam boiler is expressed in
(A) Kg/hr of fuel burned (B) Kg/Kg of fuel burned
(C) Kg.hr/Kg of fuel burned (0) KJ/Kg of fuel burned

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