Improvements in Water Tube Boilers.
Year: 1890

page_text: Date of Application, 22nd May, 1890
Complete Specification Left, 29th Jan., 1891-Accepted, 14th Mar., '1391
PROVISIONAL SPECIFICATION.
Improvements in Water Tube Boilers.
We, CHARLES JOHN GALLOWAY and JOHN HENRY BECKWITH, both of
Knott Mill Iron Works, Manchester, in the County of Lancaster, Engineers, do
hereby declare the nature of this invention to be as follows :—
Our invention relates to that class of boilers in which there are two water
chambers connected by a number of tubes around which play the flames and hot
products of combustion from the furnace. The water chambers extend upwards
above the tubes and open into a common horizontal chamber affording a water and
steam space.
Such boilers are usually set so that the tubes which connect the
water chambers are somewhat inclined in order that the water heated and the steam
generated in the tubes shall flow freely along the tubes to their upper ends and
thence up one of the end chambers into the horizontal chamber above, from which
the cooler portions of the water descend the other end chamber to pass again
through the tubes.
There is thus produced a rapid circulation causing such ebullition and commotion
of the water in the upper chamber that the steam, as it passes from the chamber, is
apt to carry water spray with it. One of the objects of our invention is to prevent
this violent commotion of the water by dividing the upward current by a number of
inclined partitions radiating from the mouth of the end chamber, so that the current
is divided into a number of separate currents expanding in width and losing velocity
as they ascend and flow towards the farther end of the water space, the steam
separating itself from them gradually and uniformly along the whole length of the
chamber.
The mouth of the farther water chamber down which the circulation current has
to descend, we, by preference, raise some distance above the bottom of the horizontal
chan.ber, so that there is in the lower part of the chamber a layer of undisturbed
water in which deposit of impurities can take place; and we provide a blow off
cock by which these can from time to time be blown out.
For the purpose of cleaning the exterior of the water tubes we utilise the stays of
the water chambers in the following manner. We make these stays tubular and
screw or otherwise fix them into the two sides of each water chamber, placing the
stays preferably in such positions that one of them is in the middle of the space
between a group of the water tubes.
Usually, the perforations of these stays are closed by plugs or covers, to prevent
access of air into the flame chamber, but some of them may be left open to admit
air locally for promoting combustion. When it is desired to clear the exteriors of
the water tubes from soot or other matter deposited on them, we insert, through the
perforation of a stay, a nozzle by which we direct a jet of steam on the exterior of
the tubes within reach of the jet, and we repeat this at the different stay openings,
the nozzle being connected to a flexible tube so that the jet can be applied through
any of the stays.
In some cases, instead of using a steam jet as above described, we may insert,
through the stays, brushes or other tools suitable for clearing the exteriors of the
tubes.
Dated this 22nd day of May 1890.
ABEL & IMRAY,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Water Tube Boilers.
We, CHARLES JOHN GALLOWAY and JOHN HENRY BECKWITH, both of
Knott Mill Iron Works, Manchester, in the County of Lancaster, Engineers, dc
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:―
Our invention relates to that class of boilers in which there are two water
chambers connected by a number of tubes around which play the flames and hot
products of combustion from the furnace. The water chambers extend upwards
above the tubes and open into a common horizontal chamber affording a water and
steam space. Such boilers are usually set so that the tubes which connect the
water chambers are somewhat inclined in order that the water heated and the steam
generated in the tubes shall flow freely along the tubes to their upper ends and
thence up one of the end chambers into the horizontal chamber above, from which
the cooler portions of the water descend the other end chamber to pass again
through the tubes. There is thus produced a rapid circulation causing such
ebullition and commotion of the water in the upper chamber that the steam as
it passes from the chamber is apt to carry water spray with it. One of the
objects of our invention is to prevent this violent commotion of the water and
we effect this by dividing the upward current by a number of inclined partitions
radiating from the mouth of the end chamber, so that the current is divided
into a number of separate currents expanding in width and losing velocity as
they ascend and flow towards the farther end of the water space, the steam
separating from them gradually and uniformly along the whole length of the
chamber. The mouth of the farther water chamber down which the circulation
current has to descend, we raise some distance above the bottom of the horizontal
chamber, so that there is in the lower part of the chamber a layer of undisturbed
water in which deposit of impurities can take place; and we provide a blow off
cock by which these can from time to time be blown out.
For the purpose of cleaning the exterior of the water tubes we utilise the
stays of the water chambers in the following manner. We make these stays
tubular placing them preferably in such positions that one of them is in the
middle of the space between every three of the water tubes. Usually the per-
forations of these stays are closed by plugs or covers, to prevent access of air
into the flame chamber, but some of them may be left open to admit air locally
for promoting combustion. When it is desired to clear the exterior of the water
tubes from soot or other matter deposited on them we insert through the perfora-
tion of a stay a nozzle by which we direct a jet of steam on the exterior of
the tubes within reach of the jet, and we repeat this at the different stay openings,
the nozzle being connected to a flexible tube so that the jet can be applied
through any of the stays.
Fig. 1 of the accompanying drawings, is a longitudinal section, and Fig. 2 is
an end view of a boiler embodying our invention. From the fire A the flames
and hot products of combustion are caused by baffle plates B to take a zig zag
course between the tubes as indicated by the arrows to the flue leading to the
chimney. At the top of the front water casing C where it communicates with
the steam and water chamber D we form between inclined diverging plates E
a number of expanding passages dividing the currents of mixed steam and water
that ascends from C, gradually retarding the divided streams and allowing the
eam to separate quietly therefrom. At the top of the passage by which the
fear water casing communicates with the chamber D we provide a part G
raised above the bottom of D so that impurities may become deposited in the
quiescent water below without descending by G to F; these impurities may from
ime to time be cleared out by opening a blow off cock or valve applied at H.

page_text: The stays K of the water chambers C and F are tubular and preferably so
placed that there is one between every three of the tubes T as shewn in Fig. 2.
Usually these tubular stays are closed by plugs or covers, or some of them may
be left open for admission of air to promote combustion.
For the purpose of clearing soot off the tubes T we introduce through any
of the tubular stays K a nozzle L connected by a flexible tube to a steam pipe,
so that we can direct a jet of steam along the surface of the tubes within range
of the jet thus sweeping off the matters adhering to them. Obviously scraping
or other tools might also be introduced through the tubular stays.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
A water tube boiler having tubular stays for its water chambers, having a set
of divided expanding passages for the current ascending from the higher water
chamber, and having the mouth of the passage from the lower water chamber
raised above the bottom of the upper chamber, all substantially as and for the
purposes herein set forth.
Deted this 20th day of January 1891.
ABEL & IMRAY,
Agents for the Applicants.