Improvements in Tubulous Steam Boilers.
Year: 1895

page_text: Date of Application, 14th May, 1895-Accepted, 15th June, 1895
Improvements in Tubulous Steam Boilers.
I, ALFRED BLECHYNDEN, of 276 Abbey Road, Banow 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 certain improvements in tubulous steam boilers of the
typo having an upper horizontal steam and water chamber connected by a group
or groups of tubes to a lower horizontal water chamber or chainbers though a part
of the invention is applicable to boilers varying somewhat from the type above
described.
My invention will be best understood by describing same with reference to the
accompanying drawings.
In Fig. 1 is shown a boiler of the type having an upper horizontal steam and
water chamber A and a pair of lower horizontal water chambers B connected to
the chamber A by means of groups of sloping tubes C which may be straight on
curved (the latter being shown on the right hand side of Fig. 1), the furnace D
being arranged between them In a boiler of this or similar type and where there
is a part of the shell (such as E) of the upper chamber D of a sufficient area to
accommodate them I attach tubes having their lower end closed and commonly
known as "Field" tubes F projecting downwards towards the file and so crense
the heating surface of the boiler and protect the lower part of the shell from the
great heat of the ne
4
In order to distribute the gases more uniformly over the surfaces of the tubes 1
employ a regulating baffle of distributing plate as shewn at G This is arranged
with slits or perforations so as to control the flow of gases and to ensure that each
part of the heating surface shall be effective. In some cases I prefer to employ
two such plates one outside the other and to operate one of them by suitable
means so that it can be moved at will in such Д manner that it will when
so moved partially close or open the slits or holes and regulate the opening to suit
varying rates of consumption of fuel.
In place of the arrangement shown I may employ Venetian shutters or louvres
but I prefer the auangement described.
Such regulating plates are particularly adapted to the particular form of boiler
shown but it is evident that they are applicable to other forms with tubes arranged
at other angles
Figs 2 and 3 are respectively elevation and section of a convenient arrangement
of the plates C in which it will be seen that they may be made in two parts and
operated from shafts GG by means of cranks or links G'G', or they may be in
more than two parts.
In the case of boilers with "diowned" tubes or tubes whose upper ends when
terminating at or slightly above the tube plate are covered by water when it is at
the working level, I prolong the upper ends of the tubes (by prefereuce of those
rows next to the fire in which the evaporation is most vigorous) up to or above
the water level. These prolongations may be parts of the tubes themselves as
shewn in Fig. 4 but I prefer to make them separate and portable inserting them
into the upper ends of the tubes as in the left hand side of Fig 5 or making them
of sufficient size to pass over their upper ends which would prolong a little
through the tube plate for that purpose as shown in the left hand side of Fig. 6 or

page_text: they may he screwed or otherwise affixed to them
In some cases 1 prefer to fix
them in groups. They may be straight or bent and may be fitted with a deflector
or dash plates H as shown. The effect of prolonging the tubes is to considerably
assist the circulation between the upper and low or chambors.
In boilers of the class which consist of chambers connected by tubes (straight or
curved) and where the tubes are of such a length that they cannot, as in the
l'regardien type of boiler, he withdiawn within one of the chambers, I provido
holes in the shell of one, or more, of the chambers at the opposite side from the
tube plate and cover the holes by domes or by a pocket or chamber leaving space
enough to enable the tubes to be withdrawn so far through the holes in the shell,
so that their other ends clear the tube plate, when they may be inclined and with-
dawn into the chamber, the holes being made laige enough for that purpose.
Sometimes I prefer to curve the tubes with the object of reducing the number of
holes provided for their withdrawal.
In the drawings Fig. 7 shews the upper chamber A provided with two rows of
small domes J one being placed over each of the holes in the shell of the chamber
the drawing shewing how a tube is withdrawn from the group of tubes C. Fig. 8
18 a longitudinal section of one of the drums shewn covering a hole while in Fig 9
there is shewn in longitudinal section a chamber A with a long pocket J' covering
a number of holes.
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 18:
1. In a tubulous steam boiler of the type described the arrangement of Field
tubes substantially as and for the purpose set forth.
2. The various constructions and anlangements of regulating baffle or distributing
plates for controlling the flow of gases through the tubes of steam boilers of the
type substantially as described.
3. In a tubulous steam boiler of the type descubed the employment of
prolonged tubes in the upper chamber with or without deflectors or dash plates for
the purpose set forth
4. In a steam boiler of the type described means for enabling the tubes to be
withdrawn though the upper chamber substantially as described
5 In a steam boiler the construction and arrangement of the parts for enabling
the tubes to be withdrawn through the upper chamber substantially as described
and illustrated in Figs. 7 to 9.
Deted thus 14th dow of ll 100
PHILIP M JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent,
For the Applicant