A Non-conducting Covering for Steam Boilers and the like.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
A Non-conducting Covering for Steam Boilers and the like.
I, JAMES AUGUSTINE DUFF, of Pearl Works, Otter Street, Belfast, County
Down, Merchant, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improved means for covering boilers and it has for
its object the making of the covering in sections and the arranging and securing
of these sections upon the boiler shell so as to admit of the removal of any or
them without materially disturbing the adjoining sections and in this way
to facilitate examination and caulking of leaky seams or rivets and also to com-
pletely localise damage to covering from same.
Each section of the covering is composed of a shallow rectangular curved
pan having wires strung across its length and breadth at about midway of its
depth into which pan the non-conducting-composition is run in a plastic state,
the wires being thereby embedded in the composition and serving to support
the composition atter it has dried and set. In lieu of or in addition to the cross
wires the sides of the pan may have lips formed on them to retain the com-
position in place within the pan.
At a convenient stage in process of drying the composition is perforated three
quarters of its depth preferably with heckle pin stamps to ensure minute per-
forations. These perforations are then closed up on surface with a finishing
skin of composition, or in lieu thereof the composition may be deeply corrugated
or grooved on the surface. The whole section is thereafter lacquered to render
it thoroughly waterproof.
In arranging the sections for example on the shell of a double ended marine
tubular boiler, I provide a retaining bar for the sections, extending about half
round said shell, and bind it thereto by means of studs secured to the boiler
shell and nuts, thimbles being provided round the studs to keep the retaining
bar at a distance slightly greater than the depth of the pan. This retaining
bar may either be rigid or be slotted at stud holes to allow free movement for
tightening down by means of knees or otherwise. The first retaining bar is
secured to the boiler shell with its centre line at a distance from one end of
the boiler approximately equal to the length of the covering section, and one
end of the section is inserted under the bar the other end covering the seam
formed by the junction of the boiler end and the first side plate. This section
is held in position by a set pin through retaining bar clamping it underneath
the bar until the other sections have been placed similarly in position all round
this portion of the boiler shell; a second and similar retaining bar being secured
in the same manner to the lower portion of the circumference of the boiler.
These bars together form one complete bar equal to the circumference of the
boiler, less the breadth of the butt strap of the boiler shell, the object of stopping
the section retaining bar short of the butt strap joint being to admit of one or
more sections being placed over the joint entirely independent of strapping of

page_text: '
other sections and thus facilitate repairs. This section or sections are retained in
position by a short bar extending from the stud at one end of the above mentioned
bar to the stud at its other end A binding strap preferably not secured in
any way to the boiler shell may be placed around the sections near their free
ends, and tightened to clamp the sections to the boiler shell. On the other
side of the centre line of the retaining bar the sections are placed in a similar
manner, and at the centre of the length of the boiler shell retaining bars are
secured in a similar manner and covering sections placed under them as already
described. The circumferential seam and rivets between the free ends of these
latter sections and the free ends of those under the first mentioned retaining
bar are filled in with like sections retained in position upon the boiler shell by
cross straps extending between studs on the free ends of the sections. The other
length of the boiler shell extending from the centre to the other end is covered
in the same manner, the butt strap being in each case covered by one or more
sections strapped independently.
Dated this 26th day of September 1899.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow,
Agent for the Applicant.
I, JAMES AUGUSTINE DUFF, of Pearl Works, Otter Street, Belfast co. Down,
Merchant, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in
and by the following statement:—
This invention relates to improved means for covering boilers and it has for
its object the making of the covering in sections and the arranging and securing
of these sections upon the boiler shell so as to admit of the removal of any of
them without materially disturbing the adjoining sections; and, in this manner
to facilitate examination and caulking of leaky seams or rivets and also to
completely localise damage to the covering due to such leaky seams or rivets.
In order that my said invention may be properly understood I have hereunto
appended, by way of illustration or example, an explanatory sheet of drawings,
whereon,
Fig. 1 is a side view of a double ended marine boiler showing the covering
applied to a portion of the same.
Fig. 2 is a cross section of the boiler showing the various covering sections
secured to the shell.
Fig. 3 is a detail view, drawn to an enlarged scale, of a portion of the shell
and its covering and showing the method of fastening the sections thereto.
Figs. 4 and 5 are respectively a cross section and plan of one of the rectangular
pans for containing the non-conducting composition.
Fig. 6 is an elevation and Fig. 7 a plan of a donkey boiler having the covering
applied thereto. The boiler in Fig. 6 is shown lying on its side.
Fig. 8 is a side view and Fig. 9 an enlarged section showing the covering as
applied to a length of steam piping.
Referring to the drawings whereon the same reference letters wherever
repeated indicate the same or similar parts.

page_text: In carrying out the invention each section of the covering is composed of
a shallow rectangular curved pan a constructed as shown at Figs. 4 and 5 of
the drawings. This pan may be made in various ways but, preferably consists
of two. light angle irons b, c, and two end pieces or strips de joined together
by means of rivets and. suitable corner. pieces f. A bottom plate g. is riveted" to
the angle. irons. The whole is or may be galvanized.
Wires or the like h
are strung across the length of the pan at about midway of its depth. The
non-conducting composition A is run into each pan in a plastic state and the
wires being thereby embedded in said composition serve to support it after it
has dried and set.
If desired, in lieu of the cross wires h or in addition thereto, the sides of the
pan may have inwardly turned lips or the like formed on them to retain.or
assist in retaining the composition in place within the pan.
At a convenient stage in the process of drying, the composition is, or maybe,
perforated three quarters of its depth preferably with heckle pin stamps to
ensure minute perforations.. These perforations are then closed up, on their
surface with a finishing skin of composition.
In place of perforating the composition as above described, it may be deeply
corrugated or grooved on the surface and the whole thereafter lacquered* to
render it thoroughly waterproof.
In applying the covering to a double ended marine boiler, such as illustrated
at Figs. 1 and 2 of the drawings, I provide retaining bars. for the sections:
These retaining bars are made in parts each part extending partially round the
shell of the boiler and being attached thereto by means of studs and nuts k
(see also Fig. 3). Thimble pieces are provided and fit round the studs j.
These thimble pieces are made of a slightly greater depth than the pans a and
serve to keep the retaining bars i at the proper distance from the shell of the
boiler. The retaining bars i may either be rigidly secured in place or be madė
with slots so as to permit of tightening up or adjustment, the slots allowing
"play room for the studs j.
وو
When covering a boiler having three plates in the circumference, such as
illustrated in Figs. 1 and 2, the first retaining bar i is secured to the boiler
shell with its centre line at a suitable distance from one end of the boiler and
one end of a section B, laid bottom upwards, is inserted under the bar, the other
end covering the seam formed by the junction of the boiler end and the first
side plate. This section is held in position, by set pins m (see also Fig. 3);
passing through the retaining bar i into the bottom g, and then the other sections
are successively placed similarly in position all round this portion of the boiler
shell. A second and similar retaining bar is secured in the same manner
to the lower portion of the circumference of the boiler and sections B' of
covering secured to it in the same manner as the sections B. Then a third
bar with its sections 132 of covering is similarly secured in placet These
bars i,,, together form practically one. bar or hoop which is equal to the
circumference of the boiler less the breadth of the butt straps n of the boiler
shell. The object in stopping the retaining bars i, 1, 2, at the butt straps n
is to admit of sections of the covering being placed over the joints entirely
independent of the strapping of the other sections and thereby facilitate exam-
ination and caulking. These sections () are retained in position by means of
short bars extending from and being secured by the stud j at one end and
the stud at the other end. After all the sections are secured in place the
set pins m and the nuts are tightened up.
The second series of sections of covering A are secured in position in a similar
manner and held in place by the second retaining bar or hoop and so on with
each series of sections.
Binding straps preferably not secured in any way to the boiler shell may be
placed around the sections at their free ends and tightened up by "means of

page_text: a bolt and nut or like arrangement thereby clamping the sections securely in
place round the boiler.shell.
The circumferential seams and rivets between the free adjacent ends of the
series of sections are covered by sections of covering C retained in position upon
the boiler shell by cross straps s extending between and secured by studs t¹
at the free ends of the sections. These studs are, preferably, fixed through
the bottoms of. the pans.
The joints at the butt straps are in each case covered by independent sections 0.
:. If desired the retaining bars i need only be studded to the boiler at each
end of the bars that is at the ends next the butt straps. In any event only
sufficient..studs. need be used to hold the retaining bars in place with enough
rigidity to retain each pan temporarily in place until all the pans are fitted.
In the case of a donkey boiler (see Figs. 6 & 7) the bars i would not be
secured to the boiler by studs but be simply made in the form of hoops and
rolled to a diameter about four or five inches greater than the diameter of the
boiler. These hoops would be passed round the boiler and tightened up by
screw bolts r. m (Fig. 7) are the pins for holding the sections in place. The
top sections may be secured together by straps and to the top bar i by straps u¹.
Thimbles or distance pieces would be used to keep the hoops at the proper dis-
tance away from the boiler shell whilst the sections were being fitted in place.
. In the case of covering for steam pipes (see Figs. 8 and 9) the ends of each
pan may be formed by ordinary stamped "bottoms" of paint drums or roving
cans split in halves whilst the curved body of the pan may be rivetted to these
ends. Of course a hole equal in diameter to the outside diameter of the steam pipe is
cut out of the "bottom" before splitting. The sides of the body of each pan are
flanged and these flanges are corrugated or beaded so as to interlock as shown
at Fig. 9. The flanged sides are not made as deep as the covering but slightly
less so as to prevent the iron touching the pipe and also to allow sufficient
cushion to compensate for the slight differences in girth of cast pipes. The
sections A, Fig. 8, are secured in place by hoops i bolted together at the ends.
"
.6
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what
I consider novel and desire to claim. is:-
1. A non-conducting covering made in sections each section consisting of a
hollow pan filled with non-conducting composition, substantially as hereinbefore
described.
2. A boiler covering section consisting of a hollow metal pan having wires
or equivalent stretched across it and filled with non-conducting composition
substantially as hereinbefore described with reference to the drawings annexed.
3. The method of covering boilers; substantially as hereinbefore described with
reference to the drawings annexed.
Dated this 25th day of June 1900
H. D. FITZPATRICK,
100, Wellington Street, Glasgow, Agent.