Improvements in Tubular Steam Boilers.
Year: 1893

page_text: Date of Application, 29th Nov., 1893
Complete Specification Left, 21st Aug, 1894-Accepted, 22nd Sept., 1894
Improvements in Tubular Steam Boilers.
I, ALFRED BLECHYNDEN, of Cavendish Park, Barrow-in-Furness, in the
County of Lancaster, Engineer, do hereby declare the nature of this invention to
be as follows:-
My invention relates to improvements in tubular steam boilers of the class in
which an upper steam and water chamber is connected with a pair of lower
chambers (preferably of D section) by means of nests of tubes, the upper
chamber being at the apex of the triangle so formed though the invention is
equally applicable to any form of tubulous boiler having one or more groups of
tubes connecting two chambers.
According to my present invention I form in the upper part of the steam and
water chamber or in the lower part of the lower or water chamber or chambers or
in both one or more rows of holes fitted with suitable plugs or doors on the
removal of which plugs or doors I am enabled to withdraw and replace the
tubes.
In order to reduce the number of holes for this purpose I curve all or some of
the tubes to facilitate the removal and replacing of same.
Dated the 29th day of November 1893.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent,
For the Applicant.
COMPLETE SPECIFICATION.
Improvements in Tubular Steam Boilers.
I, ALFRED BLECHYNDEN of Cavendish Park, Barrow-in-Furness, in the
County of Lancaster, Engineer, 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 :-
My invention relates to improvements in tubular steam boilers of the class in
which an upper steam and water chamber is connected with a pair of lower
chambers (preferably of D section) by means of nests of tubes, the upper chamber
being at the apex of the triangle so formed, though the invention is equally
applicable to any form of tubulous boiler having one or more groups of tubes
connecting two chambers. According to my present invention I form in the upper
part of the steam and water chamber, or in the lower part of the lower or water
chamber or chambers, or in both, one or more rows of holes fitted with suitable
plugs or doors, on the removal of which plugs or doors I am enabled to withdraw
and replace the tubes. In order to reduce the number of holes for this purpose I
curve all or some of the tubes to facilitate the removal and replacing of same.
In the accompanying drawings it will be seen that my invention is illustrated as
applied to the three chambered type of boiler above described.
.
Fig. 1 is a cross section of such a boiler.
Fig. 2 is a longitudinal section on line xx, Fig. 1.
Fig. 3 is a detail showing one form of plug, and
Fi
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page_text: The upper steam and water chamber 1, is connected to a pair of lower water
chambers 2, by tubes 3 which may be curved as shown.
The chambers 2 may be of ☐ section, the flattened portion 4 forming the tube
plate as shown. These tube plates are in some cases preferably thickened as
shewn, to compensate for the weakening of them by the number of tubes inserted
therein.
The grate is represented by the line 5, and 6 are tubes which start from
different levels in the upper and lower chamber but are bent so as to run side by
side at 7, and form a wall to prevent the escape of heat.
For the purpose of withdrawing and inserting the tubes 3 I form in the upper
chamber plug holes 8 which may be closed by plugs 9 as shown in Figs. 1 and 2,
the holes being of considerebly larger diameter than the tubes 3. In the form
shown the plug 9 has a short bolt 10 attached to it which passes through a washer 11
which bears on a re-enforcing plate 12, the bolt 10 being provided with a nut 13.
Screw plugs or plugs of other suitable forms may however be employed.
It will be seen that when the boiler is emptied and the plug 9 removed the
tubes 3 of the group after being loosened from the bottom chamber 2 may be
withdrawn through the plug holes 8 opposite to same as shown by the dotted lines
in Fig. 1, the curve of the tubes facilitating the operation. The tubes are inserted
into holes in the tube plate of the upper chamber, such holes being of slightly
larger diameter than the tube, the latter being then expanded into same as usual.
The increased size of the holes will be found to allow the tubes when being
withdrawn being angled sufficiently to pass through the plug holes easily.
Each plug hole 8 will serve for the withdrawal of a number of tubes. The
tubes are withdrawn in the ordinary way. In Fig. 41 employ only one row of
plug holes 8, and use curved tubes 3, all the tubes of each group being curved in
one direction only as shown, so that the tubes of each group may be drawn out
through the one row of holes as illustrated.
It will be evident that in the case of Fig. 1 a few of the centre tubes of each
group may be straight, and that in Fig. 4 a few of the outside tubes (or those
nearest the tubes 6) of each group may be straight, or that each group may be
made up of straight and curved tubes in any proportion so long as all of them may
be withdrawn through the plug holes. Although the tubes of each group are
shown in Fig. 1 as all passing through the same set of holes it will be evident that
if the inner portion of each group were sufficiently curved, the tubes forming such
curved groups might be withdrawn through the holes directly above same.
It will be evident that although the openings in the shell for the withdrawal of
the tubes have been described above as applied to the upper chamber, they may be
applied to one or both of the lower chambers should it be found desirable.
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 :-
1. In a tubular steam boiler an upper and lower chamber, a group or groups of
curved tubes connecting them, openings in the upper or lower chambers or in both
for the purpose of withdrawing the tubes through, and plugs or the like for closing
the openings, substantially as described.
2. In a tubular steam boiler an upper chamber, a pair of lower chambers, a
group or groups of tubes connecting the upper with the lower chambers, some of
said tubes being straight and some curved, openings in the upper chamber through
which the tubes are adapted to pass, and plugs or the like for closing the holes,
substantially as described.
3. In a tubular steam boiler an upper chamber, a pair of lower chambers, a row
of plug holes in the upper chamber, groups of curved tubes connecting the upper
with the lower chambers adapted to pass through the plug holes, and plugs for
closing the holes, substantially as described and illustrated in Fig. 4.

page_text: 4. The arrangement of parts whereby the tubes connecting the chambers can be
withdrawn through openings in the upper chamber, substantially as described and
illustrated in Figs. 1 and 2.
5. In a boiler having groups of tubes connecting two or more chambers, said
tubes arranged to be withdrawn or inserted through holes in one or both of
the said chambers, curving the tubes with the object of reducing the number of
holes necessary for the withdrawal or insertion of the tubes, substantially as
described.
Dated the 20th day of Auest 1894
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent,
For the Applicant.