Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
" 3.~4773
Ihe present invention relates to a separator to
be attached to a pipe of gas such as vapor or compressed air
to separate water (e.g. condensate) from the gas to the exterior.
Particularly, it is concerned with a gas-water separator for
separating gas and water ~rom each other by the action of a
centrifugal force induced by rotating fluid.
In this type of a gas-water separator, fluid is
rotated at an upper portion within a casing and water drops
contained in gas are shaken out to the outside by the action of
the resulting centrifugal force and thereby separated. The gas
is passed to an outlet side, while the separated water drops
are discharged to the exterior of the casing by a drain valve
disposed in a lower portion within the casing.
According to the structure of a conventional gas-
water separator, a cylindrical partition wall member is disposed
in an upper portion within a~ casing to form an annular space
between the partition wall member and the casing located out-
side the partition wall member, a multitude of obliquely
downwardly inclined rotary vanes are disposed radially in the
annular space, and upper and lower portions of the annular
space and an inside bore of the partition wall member are
connected to an inlet side, a drain valve portion and an outlet
side, respectively. In this structure, fluid from the inlet
is rotated in the annular space by the rotary vanes, so that
the water drops are shaken out to the outside by the action of
a centrifugal force. The water drops thus separated flow down
and are discharged to the exterior by the drain valve. The gas
at a central part of the rotating flow moves toward the outlet
side through the inside bore of the partition wall member.
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~3477~3
In the above conventional structure, the water drops
are partially carried out to the outlet side even if the rotating
flow is strengthened and it has been impossible to enhance the
gas-water separation efficiency beyond a certain degree.
This is because there merely is utilized the law of
nature that when fluid is rotated, the larger the mass, the
more outward are shaken out the fluid by the action of a cen-
trifugal force, so very small water droplets turn in from the
outside to the inside along the surface, therefore they are
carried to the outlet side together with gas.
It is a technical subject of the present invention
to add a means for catching water drops and shaking them out
to the outside positively in a gas-water separator provided with
rGtary vanes.
According to a technical means adopted in the present
invention to accomplish the above technical subject, obliquely
downwardly inclined walls and spiral walls are formed on an
outer peripheral wall of a cylindrical partition wall member
which spiral walls are each projected gradually outward from
an upper toward a lower end of each said inclined wall and
connected stepwise to a radial end wall at the lower end of
the inclined wall.
The above technical means has the following function.
An annular space is formed over the outer periphery
of the cylindrical partition wall member and the obliquely
downwardly inclined walls are positioned in the annular space
so fluid is changed in movin~ direction into an obliquely
downward direction when passing through the annular space.
Consequently, the fluid rotates in the annular space because
of its continuity and this rotation extends to above and below
the inclined walls. That is, the fluid enters the annular
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space while rotating and goes out also under rotation.
Since the spiral walls are projecting outward
gradually from upper ends toward lower ends of the inclined
walls, the fluid moves more outward than a tangential direction
of the annular space and is blown in a better condition against
an inner wall of a casing located outside. Further, since
the width of the annular space becomes smaller toward the lower
ends from the upper ends of the inclined walls, the speed of the
rotating flow increases gradually and becomes maximum at the
lower end portion.
Moreover, since the spiral walls are connected
stepwise to the radial end walls at the lower ends of the
inclined walls, the width of the annular space expands suddenly
at those end wall portions. Consequently, as the fluid rotates,
the pressure near the end walls drops and the water drops
adhered to nearby wall surfaces gather at the connection edges
between the spiral walls and the end walls, then are blown
off by the strong rotating flow whose speed has reached its
maximum at those connection edge portions as previously noted
and are blown against the inner wall of the outside casing.
The present invention brings about the following
peculiar effects.
Not only a gas-water separation is effected by
the action of a centrifugal force induced by fluid rotation,
but also water drops are gathered positively at the connection
edges between the spiral walls and the end walls and the speed
of the rotating flow is rendered maximum at those edge portions
to blow off the water drops from the same portions and allow
them to be blown against the inner wall of the outside casing.
~34773
Therefore, the gàs-water separation efficiency is extremely
high.
It is not that the speed of the rotating flow is
merely increased, but that the width of the annular space is
rendered minimum at the lower end portions of the inclined
walls to thereby render the speed of the rotating flow maximum
at important points, namely, at the lower end portions of the
inclined walls~ Therefore, the rotating flow is gentle before
and behind those portions, thereby preventing the water drops
from being carried to the outlet side together with gas or
preventing the water surface at the drain valve portion from
being disturbed and causing a malfunction of the drain valve.
If the following are taken into consideration in
practicing the present invention, better function and effect
will be obtained~
If a longitudinal wall which projects radially from
the outer perip~leral wall of the partition wall member is formed
upward from an upper end of each inclined wall, the fluid which
enters the annular space while rotating strikes against the
longitudinal wall, so the water drops partially strike against
and adhere to the longitudinal wall and are thereby separated
from gas.
If at least an outer peripheral wall surface of the
partition wall member which includes the inclined walls and
the spiral walls is so formed as to have a rough skin like the
pear skin, water drops adhere to this outer peripheral wall
surface more easily and the surface speed of the rotating flow
in the vicinity of the wall surface is decelerated moderately,
thus making it possible to catch water drops on the wall
surface. m e water drops thus caught on the wall surface are
gathered at the connection edge portions as previously
described and blown against the inner wall of the outside
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347'73
casing. Ihus, water drops can be separated from gas by
adhering them to such a rough wall surface as the pear skin.
If the outer periphery of a lower end portion of
the partition wall member is projected outward gradually
downward to narrow the spacing from the inner surface of the
casing, the rotating flow again increases :its speed and separates
water from gas and is again blown against the inner wall of the
outside casing. In this case, a desired ~unction and effect
is obtained if the angle of inclination of the outer periphery
of ~he lower end portion of the partition wall member relative
to a vertical direction is set in the range of 25 to S0 degrees.
Particularly, if such inclination angle is set at 35 degrees,
the best results will be obtained.
The following description is now provided about an
embodiment illustrated which shows a concrete example of the
above technical means.
Figure 1 is a sectional view of a gas-water separator
according to the preser.t invention combined
with a reducing valve;
Figure 2 is a longitudinal sectional view of a
partition wall member,
Figure 3 is a sectional view tàken on line III - III
of Figure 2;
Figure 4 is a perspective view of the partition wall
member, and,
The embodiment of Figure 1 is an integral combination
of a gas-water separator A according to the present invention
with a reducing valve B for vapor.
A casing comprises a spring case 2 which encloses a
pressure setting spring 1 therein, a ualve case 4 in which is
disposed a pilot valve 3, a body 6 in which is disposed a
7'~3
main valve 5, a separator case body 8 which forms a gas-water
separation chamber 7, and a bottom cover 9. mese components
are formed by casting.
A diaphragm 10 formed by a thin metallic plate is
held between the spring case 2 and the valve case 4.
A lower end of the pressure setting spring 1 i5 in
contact with an upper surface of the diaphragm 10 through a
diaphragm disc ll,--while an upper end of a cap 13 attached to
a pilot valve stem 12 of the pilot valve 3 is in contact with
a lower surface of the diaphragm. m e space above the diaphragm
10 is connected to the outside air through a passage 14, while
the space therebelow is connected to a later-described output
23 through a passage 15.
An adjusting screw 17 is attached to a ceiling wall
of the spring case 2 through a stainless steel bearing 16 and
is swivel-stopped with a lock nut 18. A steel ball 20 is
disposed between the adjusting screw 17 and a spring shoe 19
disposed on an upper end of the pressure setting spring 1.
The portion of the adjusting screw 17 which projects
to the exterior is covered with a protective cap 21 which is
threadedly connected to the sprin~ case 2 removably.
The body 6 is formed with an inlet 22 and an outlet
23. m e inlet 22 and the outlet 23 are separated through a
horizontal wall 24 and are interconnected through a valve port
25 of a valve seat member which is threadedly connected to
the wall 24 . The main valve 5 is disposed below the valve
port 25 while being held in a resiliently urged state by means
of a coiled spring. Its upper end is connected to a piston 26.
m e pilot valve 3 is positioned between a passage 27
leading to the inlet 22 and a passage 28 leading to a space
formed above the piston 26. It comprises a pilot valve stem 12
7'7,~3
adapted to slide through a pilot valve seat 29 and a pilot
valve element 30 connected to a lower end of the valve stem 12.
And it is urged upward from below by means of a spring. In -the
passage 27 is disposed a screen 31.
The piston 26 is adapted to slide within a cylinder
32 which is attached to an inner periphery of the body 6, and
two annular grooves are formed in an outer periphery of the
piston, in which are disposed piston rings formed of polyte-
trafluoroethylene (PTFE) and springs inside the piston rings.
me~piston 26 is further provided with an orifice 33, which
connects upper and lower surfaces of the piston to release
therethrough a certain amount o~ fluid from the upper surface of
the piston to thereby make a pressure control.
Around the main valve 5 of the reducing valve B is
disposed a generally cylindrical double partition wall member
34. An outside cylinder is straight and it is formed lower
than an inside cylinder which is gently divergent at upper
and lower portions thereof. A tapered screen 35 is disposed
outside the partition wall member 34. Inside the partition
wall member 34 is integrally formed a connecting rod 36 on
a central axis through a rib to guide a lower portion of the
main valve 5. m e inlet 22 is connected through the screen
35 to an annular space 37 which is formed between the two
cylindrical portions of the partition wall member 34, while
the inside of the partition wall member 34 is connected to
the outlet 23 through the valve port 25 of the main valve 5.
47~7~3
In the annular space 37 are formed rotary vanes 38
integrally with the partition wall member 34. ~he partition
wall member including the rotary vanes 38 is Eormed by casing
according to a lost wax process and its wall surface is so
finished as to have a rough skin like the pear skin. OE
course, there may be used another casting method or a cutting
or another processing method, provided that at least the outer
peripheral wall surface of the partition wall member is finished
rough.
According to the lost wax process adopted in this
embodiment, the surface roughness of the wall surface is
15 to 60 ~m in terms of a maximum height Rmax according to
(micro meter)
JIS (B 0601). If the wall surface is finished rough so that
the surface roughness is not less than 10 Rmax, there will be
(micro meter)
obtained a good separation effect. Ihe wall surface to be
finished rough like the pear skin is indicated by the reference
mark C.
As shown on a larger scale in Figures 2 to 4, the
rotary vanes 38 are each composed of a longitudinal wall 39
which is projecting radially from an upper end of the inside
cylinder of the partition wall member 34 to an upper end of the
outside cylinder thereof, an inclined wall 40 which is inclined
obliquely downward from a lower end of the longitudinal wall 39
in a position between the outside and inside cylindrical portions,
and a spiral wall 41 formed at an upper surface of the inclined
wall 40 spirally from the inside cylinder toward the outside
cylinder. Five rotary vanes 38 are formed in the annular space
37. A terminal end of the spiral wall 4] is connected stepwise
to a radial end wall 42~
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7 ~?3
A lower portion of the inside cylinder of the
partition wall member 34 expands gradually downwar~ and termi-
nates in the vicinity of and at a predetermined spacing from
the inner wall of the outside cylinder. Its angle ~ rela-ti~e
to a vertical direction is 35 degrees. If the inclination
angle Q is set in the range of 25 to 50 degrees, there will
be obtained a good separation effect.
The lower cover 9 is attached with bolts to th~ lower
end of the casing 8 of the gas-water separator A to form the drain
valve chamber 7 in the interior and a spherical float 43 is
disposed within the drain valve chamber 7.
In the lower cover 9, a drain valve seat 44 is
attached to an inner end of a drain port 45. The float 43
is covered with a float cover 46 having a connection opening
47 formed in a lower portion thereof. The reference numeral
48 denotes a vent hole formed in an upper portion of the float
cover 46.
Fluid which has entered from the inlet 22 is rotated
by the inclined walls 40 of the rotary vanes 38. Water drops
contained in the fluid are shaken out and separated outside
by the action of a centrifugal force. The longitudinal walls
39 allow the inflowing fluid to drop perpendicularly and offset
the rotating flow created by the inclined walls 40 to decrease -
the flowing velocity of the rotating flow and direct it more
downward. At this time, the water drops partially strike
against the longitudinal walls 39 and adhere to the surfaces
thereof.
The spiral walls 41 serve to direct the rotating flow
more outward than a tangential direction o~ the annular space 37.
At the lower ends of the inclined walls 40 the width of ~e
annular space 37 becomes minimum and the flowing velocity
becomes maximum. Since the terminal ends of the spiral wall.s 41
are connected stepwise to the radial end walls 42, the width
of the annular space 37 expands suddenly with the connection
edge portions between the spiral walls 41 and the end walls 42
as a boundary. Consequently, as the fluid rotates, the areas
near the end walls are reduced in pressure and the water drops
adhered to the wall surface gather at the connection ridge
portions. The thus-gathered water drops are blown away from the
connection edge portions by the strong rotating flow and blown
against the inner wall of the casing 8 talso including the
inner wall of the outside cylinder cf the partition wall
member 34),
The water drops thus separated flow down along the
inner peripheral wall of the outside cylinder of the partition
wall member 34 and that of the casing 8. I~he gas which has
passed the lower end of the partition wall member 34 passes
the inside thereof and moves toward the main valve 5 of the
reducing valve B and flows out to the outlet 23, while the
separated water enters the interior through the connection
opening 47 of the float cover 46. At this time, the gas
present in the interior of the float cover 46 gets out through
the vent hole 48. The float 43 moves up and down according
to water levels to open and close the drain valve port of the
drain valve seat 44, allowing only water to be discharged to
the exterior from the drain port 45D
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