Improvements in Apparatus for Filtering Water especially applicable for Filtering Feed Water, for Steam Generators.
Year: 1898

page_text: Date of Application, 11th Mar., 1898
Complete Specification Left, 12th Dec., 1898-Accepted; 11th Mar., 1899
Improvements in Apparatus for Filtering Water especially applicable
for Filtering Feed Water, for Steam Generators.
I, DAVID ANDREW RANKINE, of Oriel Chambers, 14, Water Street, Liverpool,
in the County of Lancaster, Engineer, do hereby declare the nature of this inven-
tion to be as follows:-
-
This invention relates to filters and more especially to filters such as are used
to filter feed water for steam generators, the object being to provide in a compact
space filtering areas of considerable extent so arranged that the water may be.
filtered twice or thrice in succession.
I will first describe a filter adapted to filter the water twice in succession, which
arrangement I term a compound filter.
The casing of the filter is of cylindrical configuration, and it is provided with
inlet, outlet and by-pass valves, the arrangement of the latter being such that,
when it is open the water passes directly through it from the inlet to the outlet. .
The inlet end of the casing is provided with a removable cover but the outlet,
end is closed.
I fit inside the casing a perforated tube having a diameter of about, say, from:
three-quarters to seven-eighths the diameter of the casing. This tube has flanges
whose edges fit the walls of the casing; one of the flanges, that at the outlet
end, abuts against a projecting flange formed on the inside of the casing at the
outlet end, and the other flange has a groove formed in its face which carries a
rubber ring, which ring makes joint with the cover of the casing when the cover
is screwed up.
The inlet to the casing is placed between the two flanges of the perforated tube
so that the water has to pass through the perforations of the tube on its way
to the outlet. The tube is covered with the filtering medium arranged in the .
form of a cylindrical roll; this roll effects the first filtration. The second filtra-
tion is effected by a series of cylindrical rolls carried on perforated tubes placed
within the large tube last described and, of course, of much smaller diameter.
The small tubes are carried as follows:-
Within the larger tube, and in the same plane as the flanges thereof I carry
a pair of circular tube plates these plates are bored out to receive the ends of.
the smaller perforated tubes. The holes in one of the plates (the one at the
outlet end) are shouldered or recessed to take the body of the tube, and the holes
in the other plate take flanges formed on each of the small tubes at the inlet
end; each latter flange may have a groove in its face to carry a rubber ring,
which rings make joint with the door after the manner of the ring in the flange
of the large tube. It will be seen 'that the outlet ends of each of the small tubes
are open to the main outlet but that the other ends are closed by the door, so
that the water after passing through the filtering medium on the large tube,
!
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page_text: 2
passes in divided streams through the filtering media on the small tubes, and
is thus filtered twice in succession, and then leaves by the outlet in the usual
way. It will also be seen, from the construction described, that the whole of
the filtering media can be withdrawn in a single cartridge, or that any one or
more of the smaller tubes can be withdrawn individually. Arrangements may
also be provided so that if desired the water may pass to the outlet through the
outer tube only, or through the inner tubes only, or through both in parallel.
In some cases it is necessary to filter the water thrice in succession, in which
case I provide what I term a triple filter arranged as follows:-
I provide a cylindrical casing fitted with inlet, outlet and by-pass valves, and
having one open end fitted with a door. I divide the casing, by axial radial
ribs, into three compartments, the transverse section of each being a 120° sector
of a circle, and in each compartment I fit a filtering cartridge constructed as
follows:-
I provide two tube plates similar in shape to the section of one of the compart-
ments, these tube plates carry a series of small perforated tubes after the manner
described in connection with the tube. plates first. mentioned.
As before, each tube plate has a number of holes bored in it to carry the ends
of the small perforated tubes; one tube plate has recessed or shouldered holes
to take the body of the tube, and the other tube plate has holes to take flanges
formed on the other ends of the tubes, the said flanges being provided with
rubber rings. The tube plates are connected together by means of a series of
stays and the length over all is axially less than the axial length of the compart-
ments. Each tube is covered on the outside with a roll of filtering medium, and
each pair of end plates with the tube so covered forms a cartridge, and one such
cartridge is placed in each compartment.
Referring to the three chambers as A, B and C, the inlet is formed say in
the side of chamber A and the outlet is formed at the closed end of chamber C.
As the cartridges are shorter than the chambers there is a space left in each
chamber; in chambers. A and C this space is at the closed or back end, and in
the intermediate chamber B the space is at the door or front end. The front
ends of the tubes in A and C are closed by a plate or diapliragm which makes
joint with the rubber rings and is held in position by ribs formed on a curved
door; the opposite end plate in each case abutting against a flange formed on
the wall of the compartment; and in chamber B the back ends of the tubes are
closed by the end metal of the casing, the cartridge being held in position by
a sleeve interposed between the front end plate and the diaphragm.
The water enters chamber A passes through the tubes to the back end, thence
to chamber B, through the tubes in B to the front end, thence to chamber C,
through the tubes in C to the back end, and thence to the outlet. The water
in this way is filtered thrice in succession.
The filters are in each case provided with the usual mountings, and the by-pass
valve may be fitted with a spring to adapt it to act as a relief valve.
In some cases I prefer to construct the compound filter for double filtration
on the lines of the form described for triple filtration, in which case the cylindrical
casing instead of being divided into three compartments, as last described, is
divided into two only by a diametral wall. The tubes are divided into two sets
and in other respects the construction is similar to that described with the
exception that the arrangement of the valves may be modified by combining the
inlet and by-pass valves.
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool,
Agents for the Applicant..

page_text: "
}
COMPLETE SPECIFICATION.
*
Improvements in Apparatus for Filtering Water, especially applicable.
for Filtering Feed Water for Steam Generators.
:
...
I, DAVID ANDREW-RANKINE, of Oriel, Chambers, 14, Water Street, 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:
L
1
Jimiti "
P
This invention relates to filters and more especially to filters such as, are used,
to filter feed water for steam generators, the object being to provide in a compact
space, filtering areas of considerable extent, so arranged that the water, may be
filtered twice or thrice in succession.
ないさい
In the accompanying drawings which illustrate my invention, Figs. I and II
show a filter for filtering water twice in succession, Fig. I being an elevation
in longitudinal medial section on the line G, 'G,' of Fig. 11 and Fig. 11 being,
a cross-sectional elevation on the line H, H, of Fig. 1. Figs. 111 to VIII show.
a modification for filtering water thrice in succession, Figs. III and IV being
longitudinal sectional, elevations on the lines JJ, and K, K, respectively of
Fig. V; Figs. V, VI, and VII being cross-sectional elevations on the lines L, L,
M, M, and N,, N, respectively. of. Figs. IV and VIII; and Fig. VIII being a
sectional plan on the line O, O, of Fig. V. Figs. IX and X show -a filter-for.
filtering water twice in succession, Fig. IX being a cross-sectional elevation
on the line P, P, of Fig. X and Fig. X being a sectional plan on the line R, R,
of Fig. IX.
Throughout the drawings the same (and in some cases similar) parts are
indicated by the same reference figures, and the direction of view is indicated
in each case by the small arrows adjacent to the letters denoting the plane of
section.
Referring in the first instance to Figs. I and II; 1 is the body or casing of the
filter, provided with inlet branch and valve 2; by-pass valve 3, and outlet branch
and valve 4, the arrangement of the valves and passages being such that by..
opening the by-pass valve, the water can be passed directly from the inlet to
the outlet, after the manner common in filters of this class.
5 is a perforated tube forming a support for the filtering medium 6 which
effects the first filtration as the. water passes through it from the inlet. valve to
the central space within the tube 5. The tube 5. has flanges 7 which fit within..
the walls of the casing 1 and it is located, axially by the projecting flange or
ledge 8 and the door 9, a fluid-tight joint being made against the latter by the
inserted rings 10 of rubber or the like. The filtering material is wrapped on**
the surface of the tube, 5 between, the flanges 7 in one or more turns 'and-suitably.
secured in any convenient way.
,, •
The second filtration is effected by a set of smaller cylindrical rolls" 11 of
filtering material carried on the smaller perforated tubes 12 placed within the
larger tube 5. These rolls and tubes are broadly similar to the larger roll and
tube already described, but the outlet ends of the tubes are not flanged; they
are located by the perforated tube plates 13 and 14, which, fit within the tube 5:
and are connected by the stay bars 15, so that the tube plates and the covered":
tubes form a filtering cartridge, and when the door is in place, the cartridge
is located axially, between, the door and the projecting ledge 16' on the tube 5.
The tubes. 12 are simply, passed through the tube plate: 14, within the holes of
which the edges of their flanges. fit, but at their outlet ends they are seated in
the shouldered-recesses shown in the plate 13.
.**

page_text: The water entering by the inlet 2 filters through the larger filtering roll 6
into the space surrounding the smaller filtering rolls 11; it then filters through
these in a number of streams and passes along the interiors of the tubes 12 and
through their open outlet ends to the outlet branch 4.
It will be seen that the whole of the filtering medium can be withdrawn or
replaced as a single cartridge and that any one of the smaller tubes can be with-
drawn or replaced individually.
Referring now to Figs. III to VIII which show a modification for filtering
water thrice in succession, 1 is the body or casing provided with the door 9 and
the inlet, by-pass and outlet valves and branches substantially as before; the
casing is divided by the axial ribs or feathers 17, 18 and 19 into three compart-
ments, and in each compartment a filtering cartridge is fitted, substantially
similar to the cartridge of tubes 12 already described, except of course that the
general transverse configuration is a sector of 120 degrees instead of a circle;
it should also be noted that the cartridges are considerably shorter than the
length of the compartments so that there is an unoccupied space or pocket at one
end of each compartment.
Referring to the three compartments as A, B, and C, and terming the door
end of the casing the front and the opposite end the back; the inlet communicates
at the side with compartment A (see Figs. V and VIII), and the filtering cart-
ridge of the latter is located towards the front end, the tube plates 13 and 11*
being located between the ledge 20" and the plate 25, kept in place by the
door 9, the pocket 21° being thus formed at the back end; this pocket communi-
cates through the opening 22 in the rib 18 with the compartment B.
The filtering cartridge in the compartment B is located towards the back
thereof, its back tube plate being unperforated and abutting against the end
of the casing. The cartridge is located by the perforated plate 23 which makes
joint against the rubber rings 10 in the flanges of the tubes, and the necessary
pressure against this plate 23 is transmitted from the plate 25 by the sleeve or
liner 24. The pocket 21b, which is at the front end of the compartment B,
communicates with the compartment C through the opening 22b in the rib 19
and sleeve 24 and this latter compartment is fitted with a filtering cartridge
similar and similarly situated to that in the compartment A, leaving the pocket 21°
at its back end which communicates with the outlet passage 4.
The course of the water will now be readily understood:-it enters the com-
partment by the inlet passage 2, filters into the filtering tubes, flows through
them from front to back and passes through their open ends into the pocket 21ª..
Thence it passes by the opening 22 into the compartment B, filters into the
filtering tubes therein and flows through them from back to front into the
pocket 21. Thence it passes by the opening 22 into the compartment C and
finally filters into the filtering tubes therein and flows through them from front
to back into the pocket 21° and out by the outlet 4.
Referring now to Figs. IX and X; this construction is broadly similar to
that last described but it is of simpler form as it is adapted to filter the water
twice only in succession. A single diametral rib or feather 26 divides the casing
into two semicircular compartments D and E, the compartment D having a
pocket 21d at the back end communicating with the compartment E by the
opening 22d, and the compartment E having its pocket 21° at its front end.
The positions of the inlet 2 and outlet 4 are indicated conventionally by dotted
circles in Fig. X as they are above the plane. of section, and from what has been
said it will be readily. understood that the water entering. the compartment D,
filters into the pocket 21d and from thence enters the compartment E and filters
into the pocket 21° finally leaving by the outlet 4.
プ
I have shown; the main casing divided into two compartments in Figs. IX
and X, and into three compartments, in Figs. III to VIII, which constructions
provide respectively for double and triple filtration; it is obvious, however, that.
without departing from the principle of my invention, the casing may be
ย

page_text: divided, after a similar manner, into four or more chambers to provide for four
or more filtrations in succession.
t
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is, in filters, specially applicable for filtering feed water for steam
generators and the like.-
1. A filter, comprising a casing having inlet, outlet, and by-pass valves and
passages; a filtering roll of comparatively large diameter, provided with flanges,
and so disposed within the casing that the water from the inlet passes therethrough
from exterior to interior; and a series of filtering rolls of comparatively small
diameter so placed within the larger roll that the water after passing through
the latter passes through them to the outlet in parallel streams and is filtered a
second time; the arrangement. of the rolls being such that the smaller rolls
individually, or the whole of the filtering media collectively, as a filtering cart-
ridge, may be withdrawn through an end door which, when closed, ensures con-
tact between the jointing surfaces which determine the direction of flow; sub-
stantially as described and illustrated.
2. A filter comprising a casing with inlet, outlet and by-pass passages; a
filtering roll of comparatively large diameter having a flange extending to the
wall of the casing between the inlet and the outlet; a series of smaller rolls
carried by tube plates within the said larger roll; and a door adapted to hold.
the rolls in position axially and to ensure contact between the jointing surfaces
so that the water on its way from inlet to outlet has to pass first through the
larger roll and then in parallel streams through the smaller rolls, substantially
as described and illustrated in-respect to Figs. I and II.
3. A filter comprising a casing divided into two compartments by a longitudinal
medial partition and provided with an inlet passage and valve leading to the
one compartment, an outlet passage and valve leading from the other compart-
ment, and a by-pass passage and valve connecting the inlet and outlet passages;
two sets of filtering rolls each forming a filtering cartridge whose axial length
is less than that of the casing, one cartridge being so disposed in each compart-
ment, and at opposite ends of the casing, in such relation to the inlet, outlet,
and an opening through the partition, that water from the inlet passes through
the rolls of cach cartridge in parallel streams and through the two cartridges
in succession, on its way to the outlet; substantially as described and illustrated.
4. A filter comprising a casing divided into two compartments by a longi-
tudinal medial partition having an opening connecting the two compartments at
one end of the casing, and being provided with inlet and outlet passages at the
other end thereof; two sets of filtering rolls of axial length less than the casing,
the rolls of each set being carried by tube- plates stayed together so as to form
filtering cartridges which can be withdrawn through an end door, which door
is adapted to hold the cartridges axially in position in the respective compart-
ments and to ensure contact between the jointing surfaces which determine the
direction of flow; substantially as described and illustrated in regard to Figs. IX
and X.
5. A filter comprising a casing divided by radial partitions into three cham-
bers A, B and C, and provided with an inlet passage and valve leading to
chamber A, an outlet passage and valve leading from chamber C, a by-pass
passage and valve connecting the inlet and outlet passages, and two openings at
opposite ends of the casing which connect respectively chambers A and B and B
and C; three sets of filtering rolls of shorter axial length than the casing, s
lisposed, one in each chamber, in relation to the inlet, the outlet and the said
penings, that the water from the inlet passes in parallel streams through the
olls of each set, and through the three sets in succession on its way to the outlet ;
ubstantially as described and illustrated.

page_text: 6. In filters of the kind herein described, the mode of forming the joint at
the end of the perforated tubes on which the filtering medium is carried; which
consists in grooving the end flanges and inserting therein rings of rubber or
the like which make joint with the door, either directly," or through plates
and
sleeves, and which rings are adapted to elastically transmit, when the door is
in position, the axial pressure necessary to ensure contact between the jointing
surfaces which determine the direction of flow; substantially as described and
illustrated.
.y
7. A filter in which the casing is divided radially into three or more chambers
which communicate by means of openings such as 22 arranged at opposite ends
alternately, and in each of which chambers is placed a filtering cartridge con-
sisting of a number of filtering rolls supported on perforated tubes carried by
tube plates stayed together, the said cartridges being of shorter axial length than
the casing and so leaving communicating pockets at one end of each chamber,
the arrangement being such that water from the inlet passes through the rolls
of the individual cartridges in parallel and through the several cartridges in
succession, on its way to the outlet: substantially as described and illustrated
in regard to Figs. III to VIII.
:
T
8. The improved filter substantially as described and illustrated in Figs. I
and II.
.9.. The improved filter substantially as described and illustrated in Figs. III
to VIII.
"
10. The improved filter substantially as described and illustrated in Figs: IX
and X. .
Dated this Tenth day of December 1898
I
SLOAN & LLOYD BARNES,
34, Castle Street, Liverpool; Agents for the Applicant.