Improvements in Feed Water Filters used in connection with Steam Boilers.
Year: 1896

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 18 of the Patents, &c. Act, 1883) as allowed by
the decision of the Comptroller General of the 14th day of May 1898.
Date of Application, 30th Sept., 1896
Complete Specification Left, 11th Jan., 1897-Accepted, 25th Sept., 1897
PROVISIONAL SPECIFICATION.
Improvements in Feed Water Filters used in connection with Steam
Boilers.
We HENRY BURNETT WATSON, Engineer, High Bridge Works, City and County
of Newcastle-on-Tyne, and JOHN STANLEY WATSON, Engineer, High Bridge Works,
City and County of Newcastle-on-Tyne, do hereby declare the nature of this in-
vention to be as follows:-
Our invention has reference to improvements in Filters for purifying water
& consists of a series of flattened or oblong filtering Tubes forming supports
for the filtering medium. These filtering Tubes are arranged in a cylindrical
case between two plates, one of which forms the cover of the case. Feed-Water
to be filtered passes from outside to inside of the filtering tubes & through the
ends of the same and is controlled by a valve. The filtering tubes may be made
double or treble placed inside each other according to the extent the water has
to be purified before entering the Steam Boiler. Two or three Filters may be
worked together the feed-water passing from one to another, and thus with change
valves, either Filter can be isolated for cleaning.
To prevent undue pressure accumulating escape-valves are fitted to the case
on the external side of the filtering tubes, also sludge-cocks for blowing through
the Filters.
The filtering medium consists of towelling flannels or other suitable material
wrapped round the tubes and held in place by garters or wire clips.
By the arrangement we have designed and which we have briefly described we
get a maximum of filtering surface introduced into a minimum of space.
Dated this Twenty-ninth day of September 1896.
HENRY BURNETT WATSON.
JOHN STANLEY WATSON.
COMPLETE SPECIFICATION (AMENDED).
Improvements in Feed Water Filters used in connection with Steam
Boilers.
We, HENRY BURNETT WATSON, Engineer and JOHN STANLEY WATSON, Engineer,
both of High Bridge Works, Newcastle-on-Tyne, in the County of Northumber-
land, 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:-
Our invention relates to improvements in water filters more especially applic-

page_text: able for filtering water for use in steam generators, and has for its object to provide
a relatively large aggregate filtering area within a casing of relatively small
dimensions, and further to expeditiously effect the filtration and purification of
water in large quantity without the necessity of frequent cleansing or renewal of
the filtering material employed.
Our invention consists in the provision within the casing of a number of
reticulated or perforated cases around which the filtering medium is wrapped, of
such a form or of such a number or of such a disposition as will provide a
relatively large or a maximum filtering area, so that the internal area or dimen-
sions of such component cases shall be relatively small or the minimum necessary
for allowing the unrestricted passage of the percolating water there-through;
while the interstitial outer space may also be relatively small or the minimum
necessary to ensure the free access of the water to the surfaces of the filtering
cases.
In the accompanying drawings;-
Figures 1 and 2 illustrate in sectional elevation and sectional plan respectively
a filter made in accordance with our invention and designed for application to a
marine boiler.
Figure 3 is a modified duplex arrangement of filters in accordance with our
invention, while
Figure 4 is a plan thereof.
Figure 5 illustrates in part sectional elevation an enlarged view of a filter case
or frame, and
Figure 6 is a sectional plan thereof.
Figures 7 to 11 in sectional plan, different forms and sections of filtering cases
or frames;-
Figure 7 is a polygonal section.
Figure 8 is an oblong section.
Figure 9 is triangular section.
Figure 10 is a polygonal treble section, while,
Figure 11 is an oval double section.
Figures 12, 13 and 14 illustrate in diagrammatic sectional elevation an arrange-
ment of 3 filters with valve connections arranged for duplex working.
In carrying our invention into effect we provide a casing A preferably of
circular sectional form, having a diaphragm or false bottom surface B which
may be cast or formed integral with casing A or independently and capable of
removal. Upon this diaphragm B the filter cases or frames C are mounted,
such cases being provided with a firm and tight seat upon the diaphragm, and
being capable of ready removal therefrom. The filter casing A is provided with
a cover D which is bolted thereto and a removable cover C¹ which is set upon
the protruding heads of the filter cases C and holds the upper ends thereof in
position.
An intermediate chamber E is provided in the casing A and an outlet valve
aperture is centrally formed, through which a mushroom valve F is seated, such
valve with its stem being provided upon a bracket G bolted to the casing and
being operated by a hand wheel H. The inlet valve I is provided which with
its stem is mounted upon a bracket G and operated by a hand-wheel H. The
inlet passage J is in communication with the under surface of the relief or bye-
-pass valve K which is loaded with a spring L of determined pressure so that
when the filtering material; after an abnormal period of use becomes choked and
offers considerable resistance to the passage of the unfiltered water, the accumula-
tion of a great pressure is obviated by means of such relief valve K, which
immediately upon such determined pressure being exceeded is uplifted and the
water passes through the outlet M direct to the boiler.
This valve K is fitted with easing gear by means of which it is held open when
the filter is shut off.
The filter cases or frames C are provided with closed upper ends and with

page_text: apertures or perforations Caround their peripheral surface, upon which the
filtering flannel or material e, may be wrapped and after wrapping be clipped
and retained upon the cases or frames by means of clips, straps or bands c¹ disposed
at each end of the cases or intermediate thereof or otherwise as may be necessary.
The lower extremity of each of the cases is provided with a boss C, upon which
the case rests and whose extremity fits and is retained within the seat provided
in the diaphragm B by any suitable means, while the upper extremity of each
of the cases is provided with a screwed plug C
The action of the filter is as follows:-
-
The inlet valve I and the outlet valve F are opened and the unfiltered water
from the feed pump enters the casing A and surrounds the cases C percolating
through the filtering material wrapped thereupon and passing internally into the
cases and into the intermediate chamber E where the filtered water passes through
the common valve aperture to the outlet M, thence to the boiler as indicated by
the arrows.
When it is desired to cleanse the filter in a case where only one is employed, the
inlet valve I and the outlet valve F are closed and the bye-pass valve K is opened,
thus permitting the feed water to pass direct through the outlet M to the boiler
without filtration. The inlet valve I may be eased and the water may drain
through the sludge cocks N and O. For the purpose of cleaning the exterior
surface of the filtering material or flannel the inlet valve I is eased from its seat
and the sludge cock N is opened, while for cleansing the interior surface of the
filtering material or flannel the outlet valve F is eased and the water allowed to
drain through the sludge cock 0.
When the filtering material employed has become saturated to such an extent
as to be substantially unaffected by cleansing in this way, the cases are removed
and new material is placed thereupon, and for this purpose the cover D is
removed and each case removed singly, or if an independent diaphragm is
employed that together with the cases mounted thereupon is entirely removed
for this repair.
Figures 3 and 4 show in elevation and plan a duplex arrangement of filters
substantially the same in construction as that illustrated in Figures 1 and 2.11
A change valve P is here shown for diverting the unfiltered water from the feed
pump to one of the filters when the other is required to be cleansed. The common
inlet J is shown and the duplex change valve P works upon opposing seats within
the valve casing Q.
When it is desired to divert the water from the filter A¹ to the filter A³, the
duplex valve is screwed down to the lower seat and the supply cut off from the
inlet J of the filter A', while the upper part of the valve is opened and the feed
water issues through the inlet passage J to the filter A. It will be seen that
by means of this arrangement it is possible to filter continuously the periodic
isolation of the one filter allowing for regular cleansing while the other is in
operation.
A suitable indicator p is employed to show the position of the valve.
filtered water issues in each case to a common outlet M¹, and independent outlet
valves Fare employed as also independent bye-pass or relief valves K'. The
operation of the duplex filter is substantially the same as the single filter herein-1
before described.
Figures 12, 13 and 14 illustrate a system of continuous filtration in which
three filters are employed for duplex working, the filters in each case being
arranged and operating substantially as hereinbefore described and being used in
continuous succession. The filters A3 and A are shown in Figure 12 as being
in use, the filter A³ being the primary filter, while the filter A is the secondary
filter. The feed water passes from the pump through the inlet pipe J through
the inlet valve I through the filter A3 thence to the intermediate chamber E¹
through the valve I to the filter A into the intermediate chamber E to the
valve F thence through the outlet pipe M to the boiler.

page_text: After a determined period of filtration the inlet valve I is opened and the inlet
valve I and communication valve I³ closed, and the feed water passes from the
inlet pipe J2 direct to the filter A. The outlet valve F3 is closed so that the
water after passing into the intermediate chamber E2 passes through the com-
munication valve 15 which is previously opened through to the filter A³ into the
intermediate chamber E3 and thence through the outlet valve F' direct to the
boiler. The filter A³ is meanwhile cleansed and after a further determined period
of filtration the filter A is cut off, and the feed water passes through the valve 16
direct to the filter A5 into the intermediate chamber E3 thence through the com-
municating pipe J³ and communicating valve I' to the filter A3 passing to its
intermediate chamber through the outlet valve F3 and thence through the outlet
pipe M to the boiler.
The Figures 12, 13 and 14 show the cycle of operations, the valves being shown
closed or open as required and the direction of the feedwater in each figure
indicated by arrows.
It will be understood that two filters are continuously employed, while the
other is cut out of circuit and cleansed ready to be used as the secondary filter
when the primary filter becomes surcharged, and after a period of use as a
secondary filter the feed water is passed direct there-through and the filter acts
as a primary filter, while the other filter previously cut out of circuit and cleansed,
is used as a secondary filter and so on.
We do not limit our invention to the specific instances of construction and
arrangement herein before described as we may employ the essential features of
our invention as hereinbefore described in any modification of design to suit
particular requirements.
It is obvious that the course of the feed water may be reversed and any necessary
or desirable modifications made in the arrangement or construction to adapt the
filter for filtration of the water from the interior to the exterior of the filtering
cases without departing from the essential features of our invention, and that we
make no claim to the relief or byepass valve K.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. In apparatus for filtering fluids and more especially boiler feed water the
provision of a number of reticulated cases or frames upon which the filtering
material is wrapped, such cases or frames being of eliptical oval or oblong form,
thereby providing a relatively large superficial filtering area, a relatively small
internal area of the component cases or frames and a relatively small interstitial
area adequate for the unrestricted passage of the water substantially as described.
2. The provision of a number of apparatus in connection and communication
for filtering fluids and more especially boiler feed water, having the cycle of
operation substantially as and for the purpose herein before described with refer-
ence to Figures 12, 13 and 14 of the accompanying drawings.
3. Improvements in apparatus for filtering fluids and more especially boiler
feed water substantially as and for the purposes hereinbefore described and illus-
trated in the accompanying drawings.
Dated this 11th day of January 1807
MARKS & CLERK,
18, Southampton Buildings, London, W.C., Agents.