Improvements in Apparatus for Filtering Water, especially applicable to Apparatus for Filtering Feed Water for Steam Generators.
Year: 1896

page_text: Date of Application, 16th Mar., 1896
Complete Specification Left, 16th Dec., 1896-Accepted, 13th Feb., 1897
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Filtering Water, especially
applicable to Apparatus for Filtering Feed Water for Steam
Generators.
I, DANIEL ARTHUR QUIGGIN, of 11 Harlech Road, Blundellsands, near Liverpool
in the County of Lancaster, Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to filters and is especially applicable to filters for feed
water for steam generators, the object being to provide a filter having a very large
area of filtering material in a comparatively small space, and so arranged that the
filtering material may be readily removed and replaced.
In carrying out my invention I provide a suitable casing having an inlet and an
outlet, and I form across the water way a series of vee shaped perforated gratings,
the depth of the vees being nearly equal to that of the casing, and the apices
pointing alternately in opposite directions; when the casing is square in plan the
vee shaped gratings run across from one side to the other, but when the casing is
made circular in plan, as is usual in the case of high pressures, the gratings are,
in plan, arranged in the form of concentric circles and form a series of reversed
truncated cones.
In the square arrangement the filtering medium, which may be flannel, felt, or
other suitable material, is first cut in the form of a rectangle of width equal to
the width of the casing, (which is somewhat greater than the perforated portion of
the gratings), and of length equal to the zig zag length of the vees; the medium
is secured at one narrow end and arranged to follow the contour of the successive
gratings and then secured at the other end; the medium is placed on the pressure
side of the gratings and thus lies across the water-way, but it will be seen that its
area, on account of the zig zag gratings, is inany times greater than the transverse
area of the casing. As stated the width of the filtering medium is greater than the
overall width of the perforations, and the margin suffices to make the joint so that no
liquid can pass from the inlet to the outlet through the perforations except by
passing through the medium. Wedge shaped side pieces may also be provided and
inserted from above so as to press the margin of the medium on the plain edges
of the gratings; these side pieces may be cast integral and may be kept in position
by springs interposed between them and the removable top of the casing.
When the casing is made circular in plan the gratings consist of a number of
concentric reversely set conical surfaces, diminishing in diameter towards the centre,
and the filtering medium has consequently to be of special construction. The
medium is prepared as follows:-A conical bag of suitable material is made, the
length of the slant side being equal to the radial zig zag distance from the apex
of the central cone to the periphery of the outer one, and the base circle being
equal in diameter to the diameter of the outer cone. It will be seen that a bag
of this kind, can, by suitably folding it in reverse directions at equal distances
along the slant side, be made to just fit over the concentric conical gratings; and
if put on the pressure side and the periphery secured to the outer cone by a garter
spring, it forms a filtering medium of considerable area across the water-way and is
naturally kept in position by the water pressure.

page_text: In each of the arrangements described the filtering material can be removed
and replaced without of necessity having to disturb the gratings, which is a feature
of considerable advantage and not usually possessed in this class of filter.
Dated this 14th day of March 1896.
SLOAN & LLOYD BARNES,
Castle Chambers, 26 Castle Street, Liverpool, Agents for the Applicant.
Improvements in Apparatus for Filtering Water, especially
applicable to Apparatus for Filtering Feed Water for Steam
Generators.
I, DANIEL ARTHUB QUIGGIN, of 11 Harlech Road, Blundellsan ls, near Liverpool
in the County of Lancaster, Engineer, do hereby declare the nature of this inven-
tion 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 filters and is especially applicable to filters for feed
water for steam generators, the object being to provide a filter having a very large
area of filtering material in a comparatively small space, and so arranged that the
filtering n:aterial may be readily removed and replaced.
In carrying out my invention I provide a suitable casing having an inlet and an
outlet, and I form across the water way a series of vee shaped perforated gratings, the
depth of the vees being nearly equal to that of the casing and the apices pointing
alternately in opposite directions; when the casing is rectangular in plan the vee
shaped gratings run across from one side to the other, but when the casing is made
circular in plan, as is usual in the case of high pressures, the gratings are, in plan,
arranged in the form of concentric circles and form a series of reversed truncated
cones.
In the square arrangement the filtering medium, which may be flannel, felt, or
other suitable material, is first cut in the form of a rectangle of width equal to
the width of the casing, (which is somewhat greater than the perforated portion of
the gratings), and of length equal to the zig zag length of the vees; the medium
is secured at one narrow end and arranged to follow the contour of the successive
gratings and then secured at the other end; the medium is placed on the pressure
side of the gratings and thus lies across the water-way, but it will be seen that
its area, on account of the zig zag gratings, is many times greater than the transverse
area of the casing. As stated the width of the filtering medium is greater than the
overall width of the perforations, and the margin suffices to make the joint so that no
liquid can pass from the inlet to the outlet through the perforations except by
passing through the medium. Wedge shaped side pieces may also be provided and
inserted from above so as to press the margin of the medium on the plain edges of
the gratings; these side pieces may be cast integral and may be kept in position by
springs interposed between them and the removable top of the casing.
When the casing is made circular in plan the gratings consist of a number of
concentric reversely set conical surfaces, diminishing in diameter towards the centre,
and the filtering medium has consequently to be of special construction. The medium
is prepared as follows;-a conical bag of, suitable material is made, the length of
the slant side being equal to the radial zig zag distance from the apex of the central
cone to the periphery of the outer cone, and the base circie being equal in diameter
to the diameter of the outer cone. It will be seen that a bag of this kind, can,
by suitably folding it in reverse directions at equal distances along the slant side,

page_text: be made to just fit over the concentric conical gratings; and if put on the pressure
side and the periphery secured to the outer cone by a garter spring, it forms a
filtering medium of considerable area across the water-way and is naturally kept in
position by the water pressure.
In each of the arrangements described the filtering material can be removed
and replaced without of necessity having to disturb the gratings, which is a
feature of considerable advantage and not usually possessed in this class of filter.
I have illustrated my invention in the accompanying drawings in which Figs. I, II
and III show the form which is rectangular in plan, and Figs. IV, V, VI, VII
and VIII show the circular form. Fig. IX is a diagrammatic view showing the
method of folding the conical filtering bag.
Throughout the drawings similar parts are indicated by the same reference figures,
and in the case of sections, the direction in which they are viewed is indicated by
the small arrows placed adjacent to the letters denoting the plane of section.
Referring first to Figs. I to III; Fig. I is a sectional elevation on the line A. A.
of Fig. II; Fig. II is a transverse sectional elevation, the left hand half being on
the line B. B. and the right hand half being on the line C. C. of Fig. I; Fig. 1II is a
plan with the coven removed.
1 is the casing, provided with the inlet passage 2, outlet passage 3 an!
cover 4.
5 is the filtering medium, supported on the pressure side of the vee gratings 6,
and held in place by the wedge pieces 7, which are preferably integral with the
lower cross bars 8 and the frame 9, the sides of which are united by the curved
cross bars 10.
The gratings may be made in one piece, but they are preferably made in sections
united at their lower apices by the lugs and bolts 11; they drop freely into the
casing, resting with their lugs 11 on the bottom thereof, and being located by the
projecting pieces 12 cast on the sides of the casing.
The gratings 6 may be made of the full width of the filtering material 5,
their margins being unperforated, and the filtering material being pressed
by the wedge pieces 7 against the unperforated margins, so as to make joint
therewith. I find it preferable, however, to make the filtering material wider
than the gratings, and to house its margins and the wedge pieces in the tapered
recesses 13 in the sides of the casing; these recesses conform to the shape of the
wedge pieces, and their sides form shoulders upon which the margins of the filtering
material rest, joint being made by the pressure of the wedges.
The gratings being in place, the filtering material is placed in position, its ends
being located by the wires 14 hemmed into the material and turned down at the
ends into holes in the casing 1. The wedge pieces are now lowered into place and
the cover 4 screwed down. It will be seen that the necessary pressure to make the
joints is transmitted to the wedge pieces, from the web 15 on the cover, through
the curved cross bars 10, which have some little elasticity, and further that the
filtering material is held in the lower apices of the gratings by the cross bars 8,
and that in addition to jointing the filtering material against the edges of the
recesses 13, joints are also made at the ends of the filtering material by the end
bars of the frame 9.
Referring now to Figs. IV to IX, which show the circular form of the apparatus.
Fig. IV is an elevation; Fig. V is an elevation in diametral section, and Fig. VI is
a plan in section on the line D. D. of Fig. V; Figs. VII and VIII are drawn to
larger scale and are, respectively, a sectional elevation on a diametral plane at right
angles to that of Fig. V, and a plan with the cover removed.
1 is the cylindrical casing provided with the inlet passage 2, outlet passage 3 and
cover 4.
5 is the filtering material supported on the pressure side of the concentric
gratings 6. As shown in Fig. IX, 5 is made in the form of a conical hag a, a, a, a,
and it is successively turned inside out at the circles x, y, z, so as to assume the form
shown, adapted to conform with the gratings 6.

page_text: As before, the gratings are preferably made in sections connected below by the
lugs and bolts 11. At their upper ends the abutting edges are preferably bore:1
and turned to fit each other, so as to make a firm structure. The outer grating
has a flange 16 adapted to make joint with the recessed seating 17 in the wall of
the casing, and it is further steadied by the projection 18.
The filtering bag is kept in place by a wire ring or garter spring 19 and by the
rings 20 which are carried by the upright bars 21 from the cross piece 22 which is
pressed down by the web 15 on the cover 4, so holding the gratings and filtering
material firmly in position.
Figs. V and VI show the arrangement of passages and valves for bye-passing the
water when necessary. 23, 24 and 25 are screw down stop valves which respectively
control the inlet, bye-pass and outlet passages. Normally, 23 and 25 are open
and 24 is shut; the bye-passage 26 is then inoperative and the water flows through
the filtering material. By closing 23 and 25 and opening 24 the filter is cut out of
the circuit and the water passes, as shown by the arrows in Fig. VI, through the
bye-passage 26 and bye-pass valve 24 direct to the boiler.
These valves may also be used for reversing the flow through the filter; for this
purpose, 23 is shut, 24 is fully opened and 25 is slightly opened; a blow-off
cock screwed into the boss 27 and leading to the bilge is also opened at the
same time.
Under these circumstances, the bulk of the water passes on directly to the boiler,
but a small proportion enters the filter by the outlet valve and flows through the
filtering material in a reversed direction and so carries off some of the deposited
impurities by the blow-off cock. During this reversed flow, the displacement
of the filtering material is resisted by the bars 8 or the rings 20 as the case
may be.
28 is a davit pivoted on the side of the casing and provided with the lifting
screw 29 and tapped hand lever 30. By the aid of these the cover 4 can be readily
raised and swung out of the way for overhauling.
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. The improved apparatus for filtering water, which comprises;-a cylindrical
casing with an inlet and outlet; a series of concentric, reversely set, conical gratings
diminishing in diameter towards the centre, and placed across the water way; a
filtering medium formed as described, from a long conical bag, and adapted to
conform with the gratings; and means for holding the filtering medium in position;
substantially as described and illustrated.
2. In the improved apparatus as claimed in Claim 1, the sectional arrangement
of the gratings, and the means for holding the gratings and the filtering medium in
position; substantially as described and illustrated.
3. The improved apparatus for filtering water which comprises;-a rectangular
casing provided with an inlet and an outlet and having two of its opposite sides
formed with tapering recesses; a series of zig-zag gratings placed across the water-
way so that their surfaces conform with the tapering recesses; a filtering medium
adapted to follow the contour of the gratings; and means for securing the opposite
ends of the medium to the casing and for pressing the two margins thereof into
contact with the unperforated margins of the gratings, or the surfaces of the
tapering recesses, as the case may be; substantially as described and illustrated.
4. In the improved apparatus as claimed in Claim 3, the means for holding the
filtering medium in position, consisting of a frame such as 9 having elastic bridge
bars 10, and adapted to carry the wedge pieces 7 and cross-bars 8; substantially as
described and illustrated.
5. The combination and arrangement of parts forming the improved filter substan
tially as described and illustrated in Figs. IV to IX.

page_text: 6. The combination and arrangement of parts forming the improved filter
substantially as described and illustrated in Figs. I to III.
Dated this 15th day of December 1896.
SLOAN & LLOYD BARNES,
26 Castle Street, Liverpool, Agents for the Applicant.