DEVICES FOR PROTECTING BOILER TUBES
Year: 1888

page_text: I, WALTER HAGUE a Machinest, residing at Pittsburgh in the county of Allegheny
and State of Pennsylvania, do hereby declare the nature of my invention for
"DEVICES FOR PROTECTING BOILER TUBES," and in what manner the samo is to
be performed to be particularly described and ascertained in and by the following
statement:-
My invention relates to an improved device for protecting and equalizing the
temperature in the front portion of boiler tubes, the object being to provide a means
whereby that portion of the boiler tubes subjected to the greatest heat may be
protected or shielded, thereby to some extent equalizing the temperature of the tubes,
which allows the same to expand and contract more evenly, which being the case will
prevent leakage at that point; and with this end in view my invention consists in a
corrugated shield or inner cover placed in the end of each tube at the point of
connection with the fire-box of the boiler, together with certain other details of
construction and combination of parts as will be fully described hereinafter.
In the accompanying drawings-
Fig. 1, is a sectional elevation of a portion of a boiler tube attached to the rear
wall of a fire-box-such as are now in common use and having attached thereto one
of my improved protectors, constructed in accordance with my invention.
The
Fig. 2, is a perspective view of my improved protector, detached from the tube.
To put my invention into practice with the ordinary boiler tubes a, attached to the
rear wall b, of a fire-box, forming a part of a locomotive or other boiler, I provide a
short section of a tube c, somewhat less in diameter than the boiler tubes.
section c, is corrugated at e, in the direction of its length and provided with an
outwardly-projecting flange f. This section e, I divide by a single cut, g, extending
lengthwise of the same, for the double purpose of allowing the section c, to freely
expand and contract, and be easily entered into the tubes a.
If desired, the sections c, may be constructed without the corrugations e, as a plain
surface will answer the purpose.
In all boilers it has been ascertained by actual practice that the first leakage of the

page_text: boiler will take place at the intersection of the front portion of the tubes a, with the
fire-box, which portions are subjected to an intense heat, being in close contact with
the fire, therefore expanding and contracting unevenly with the other part of the
tubes a.
To obviate this I secure a shield or protector c, such as described, in each of
the tubes a, at a point where the same is secured to the fire chamber. The
corrugations e, along the sides of the shield c, serve to hold the same away from the
inner wall of the tube a, leaving an air space, thus protecting the tubes a, and
equalizing the temperature of the same.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
In combination with a boiler fire tube, the corrugated section c, provided with an
outwardly-projecting flange f, and cut or divided along one side in the direction of its
length, as and for the purpose described.