84. Q. What is superheated steam?

A. It is the saturated steam separated from the water from which it is

generated with more heat added, increasing its temperature from 100

degrees to 250 degrees Fahrenheit above the saturated steam temperature.

85. Q. What is the advantage of superheating or increasing the

temperature of the steam?

A. By increasing the temperature of the steam the volume of a given

weight of steam is increased and all losses due to cylinder condensation

are eliminated, which result in a reduced steam consumption, a saving in

coal and water and increased boiler capacity.

86. Q. How is the increased temperature obtained by the use of the

superheater?

A. By admitting the saturated steam into a partitioned receiver which

has a number of 1-1/2-inch pipes attached to it. These are located in

and extend nearly the full length of the large flues, the steam having

to pass through these 1-1/2-inch pipes on its way back to the receiver,

absorbs the heat from the gases passing through the large tubes, causing

its temperature to rise, or in other words, become superheated.

The Traveling Engineers' Association to Improve the Locomotive Engine Service of American Railroads Examination Questions and Answers for Firemen for Promotion and New Men for Employment · 第 80 / 436 题