MECHANICAL AND ELECTRICAL ENGINEERING DEPARTMENT.
 

NOTES ON STEAM BOILERS.
 

By L. p. Breckenridge, M. E , Prof, of Mechanical Engineering,
University of Illinois.
 

It is by no means true that because a boiler of a certain de¬
sign and setting works well in one place that its design and set¬
ting can be followed at another. It is reasonable to suppose that
if exactly the same conditions existed at each place there would
be no difference in the workings of the boilers. It seldom occurs
that exactly the same conditions do obtain. Important differ¬
ences lie in feed water, draft, kind of fuel and the fireman.

What is true of boilers themselves is also true of the details
of the settings and attachments.

Accidents and difficulties are continually occurring, each of
which brings with it some suggestion as to what should be done
to prevent its occurrence in the future. The following are re¬
ported for the first time to the profession, although it is probable
that they have been duplicated in the experiences of others be¬
sides the writer.

AN  KXPKRIBNCK  WITH  A  BIvOW-OI^F  PIPK.

This plant consisted of six horizontal Tubular Boilers, two
being 60" and four being 48" in diameter. A steam pipe con¬
nected each boiler to the main steam pipe, and in each of these
connecting pipes was a globe valve closing against the pressure
in its own boiler. Each boiler was tapped on the underside near
the back end for a 2" blow-off pipe.

The blow-off pipe from each boiler was connected to a com¬
mon 2" pipe back of the battery. The connecting pipes for the
48" boilers were 1}^" being reduced to this size by means of a
bushing in a 2" ell about 4" under the connection to the boiler.