Note: Descriptions are shown in the official language in which they were submitted.
3L~ 36
BACKGROUND OF TH~ INVENTION
_
Field of the Invention
The present invention relates to an improved valve,
more particularly; to a valve having a cartriaye which
enables exchange of the valve head and valve seat in a
very short time without detaching the body oE the valve
from the line pipe in which the valve is imcorporated.
State of the Art
. ... _ _~
In gerleral, it is desirable that valve used in
the piping system of various plants can be serviced as
quickly as possible at the time of periodical maintenance
or repair when troubled. Also, it is preferable that
servicing can be done wothout removing the valve body
from the piping. The above needs are more acute in
cases where a valve is installed in a piping through
which radioactive or toxic substances flow, and moreover,
care is required to prevent scattering of the liquid
containing the radioactive or toxic substances. Even
if sufficient preventive measures are taken, it is of
course preferable that the hazardous substances be treated
w thout direct handling thereof.
`~
With respect to ball valves, the so-called
"Gachault-Valve" whlch is separable into three parts
has been devised an~ is in use (see Japanese Patent
Publicatiorl No.28836/1969 "Ball Valve"). This type o~
valve is of a construction whereby the valve body at
the center can be demounted by loosening the bolts and
nuts connecting the flanges on both sides of the body,
and therefore, enables the saving of time and labor during
servicing. However, disassembling of the valve has some
influence on the piping system, and spilling of the li~uid
contained in the valve is unavoidable.
As another form of improvement, there is a ball
valve called the "Top-Entry"type. This valve can be
assembled and disassembled by approaching from the top o~
the valve. The ball piece of the valve can be mounted
or demounted by removing the bonnet on the top of the
valve body and loosening the seat-fastener. So, it can
be handled without removing the valve body from the pipe
line, and no spilling of liquid occurs~ Further, visual
inspection of the inner parts of the valve is relatively
easy. ~owever, loosening of the seat-~astener is
unexpectedly troublesome and takes time. Due to the
construction thereof, liquid and slaudge are apt to
accumulate in the valve, posing a large possibility of
contamination upon contact duriny servicing.
SUMMARY OF THE INVENTION
The general object of the present invention is
to provide a valve with which the time necessary for its
mainten~nce can be greatly shortened.
The specific object of the invention is to provide
a valve which is particularly suitable for use in
controlled areas of high-level radioactivity in n~clear
power 21ants.
The a~ove objects can be achieved with the present
invention in which the valve head and valve seat are
contained in a cartridge which is attachable to and
detachable from a box-type valve body. Further, these
objects can be achieved more satisfactorlly, in accordance
with the preferable embodiment of the invention, by
utilizing a bayonet-type mounting system for the attaching
and detaching of the cartridge to and from the bonnet of
the valve.
Specifically, the invention provides a
cartridge-type valve comprising a valve body, -a valve
head and a valve seat, and a bonnet and a bonnet stem,
wherein the valve body is of box-type, the valve head and
the valve seat are contained in a cylindrical cartridge
having a closed bottom and third passagewas,
characterized in that either the lower part of the bonnet
of the upper part of the cartridge has at least two
radial projections~ and that the other said part has a
groove which receives with the projections, the groove
being provided with passages for the projections so as to
permit engagement and disengagement of the cartridge and
valve body.
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DRAWINGS
Fiyures 1 through 5 show a basic embodiment of
the present invention as applied to a ball valve.
Fig. 1 is a sectional view in the plane along the
line of fluid flow and including the bonnet stem;
Fig. 2 is another sectional view in the plane
alony the line of fluid flow but transversing the bonnet
stem;
Fiy. 3 show the valve body and the cartridge, the
latter without inner parts, to show the cartridge case;
Fig. 4 is a side view of the cartridse in the
direction of arrow "A" in Fig. 3; and
Fig. 5 is another side view of the cartridge in
the dire$tion of arrow "B" in Fig. 3.
Fig. 6 shows another example of the basic embodiment
of the present invention applied to a gate valve; half of
the Figure being side elevation and the rest, vertical
sectional view.
Figures 7 through 11 show a preferred embodiment
of the present invention also applied to a ball valve.
Fig. 7 is a sectional view, similar tQ Fig. 1, in
the plane along the line of fluid flow and including the
bonnet stem;
5~
Fig. 8 is a plane view of the valve from which
the bonnet is removed;
Fig. 9 shows, like Fig. 3, the valve body and the
cartridge, the latter without inner parts, to show the
cartridge case;
Fig. 10 is a si~e view of the cartridge in the
direction of arrow "C" in Fig. 9; and
Fig. 11 is another side view of the cartridge in
the direction of arrow "D" in Fig. 9.
Figures 12A and 12~ explain the effects of the
preferred embodiment.
Fig. 12A shows the step at which the bonnet is to
be set on the valve body in which the cartridge is placed;
and
Fig. 12B show the steps of attaching and detaching
the cartridge which is engaged with the bonnet.
In these Figures, the parts indicated with denser
hatching constitute the cartridge.
5~
DETAILE~ DESCRIPTION OF PREFERRED EMBODIMENTS
_
In the basic embodiments, the cartridge-type valve
of the present invention is, in a valve comprising a valve
body, a valve head and a valve seat, and a bonnet and
bonnet stem, characterized in that the valve body is of
a box-type, that the valve head and the valve seat are
contained in a cylindrical cartridge with a closed bottom
and having passageways for flowing fluid, and that the
cartridge is attachable to and detachable from the box-
type valve body.
The following will descri~e a ball valve, a typical
valve to which the present invention is applicable, with
reference to the attached drawings.
As shown in Fig. 1 and Fig. 2, valve body 2 is of
a box-type with space for receiving cartridge 10.
Case 11 of the cartridge 10 which is attachable to and
detachable frorn the space in the body has the shape of
a cylinder with closed bottom and has passageways 12 and
13 for flowing fluid. In the case 11, ball, that is
valve head 3 is held by a combination of valve seats 4A
and 4B which are in opposite positions. The valve seats
4A and 4B are made of a suitable material, such as Teflon,
selected in view of the use of the valve. One of the
seats, 4B, is fixed to the case 11, and the other seat 4A
may be Inoved by adjuster 5 so as to give suitable contact
with the ball 3.
: 7
The adjuster 5 is moved by turniny it so as to adjust
the engagement between external thread 51 on the outer
surface of the adjuster an~ internal thread 15 on the
inner surface of the passageway 12, and is set at a suitable
position by fixing bolt 16.
The plane transversing the passageway of flowing
fluid 13 of the cartridge case 11 is, as shown in Fig. 3
and Fig. 5, a tapered plane 14 inclined toward the inside
at the lower part. The edge of the gasket 21 fixed to
the valve body 2 is shaped to mate with the above tapered
plane, and thus, close contact of the tapered plane with
the gasket gives perfect sealing of the fluid.
When tha cartridge case 11 is placed in the space
of the valve body 2, the passageway-side of the case is, due
the action between the above tapered plane and the gasket,
pushed toward the valve body 2 (to the left in the Figures)
and gasket 22 lying between them maintains the seal and
prevents ingress of the fluid into the clearance between
the cartridge 11 and the valve body 2.
As may be readily seen from the above explanation,
the parts indicated with the denser hatching in the Figures,
namely, cartridge case 11, ball 3, valve seats 4A and 4B~
and adjuster 5 in the case constitute the cartridge 10.
~S~6
~ hen the valve is to be inspected, bolts 61, 61 ~..
are loosened to remove bonnet 6 and bonnet stem 7, then,
the cartridge is ready to be taken out of the body.
If repair is necessary because of erosion or corrosion,
the cartridge is replaced with a new one, and the bonnet
is re-set~ The valve is thus ready for reuse.
The old cartridge can be repaired later over an adequate
period of time by being disassembled and, if necessary,
a part or parts thereof renewed, and reassembled.
In order that the cartridge 10 may be easily attached
to and detached from the valve body 2, it is recommended
to provide the cartridge case 11 with a groove 17 on the
inner surface of the upper part, and to use a device which
matches the groove to hold the cartridge case.
The present inv~ntion is applicable not only to
the above mentioned ball valve, but also valves of
other types such as gate valve, check valve and globe
valve. As an example, Fig. 6 shows a gate-valve to
method~
which the present cartridge ~s appliedO Also in Fig~ 6,
the~
the parts indicated with ~denser hatcning constitute
the cartridge.
s~
The preferred embodiment of the present invention,
in addition to the above descriribed basic embodiment
of the cartridge-type valve comprising a valve body,
a valve head and a valve seat, and a bonnet and a bonnet
stem, wherein the valve body is of box-type, the valve
head and the valve seat are contained in a cartridge of
a cylinder with closed bottomand having passageways for
flowing fluid, characterized in that one of the lower
part of the bonnet and the upper part of the cartridge
has at least two radial projections, and that the other
has a groove which engages with the projections and the
groove is provided with passages of the projections so
as to permit engagement and disengagement.
Again~ a ball valve, a typical valve to which the
present invention is applied, is explained below with
reference to the attached drawings.
, As shown in Figures 7 through 11~ the p~eferred
embodiment includes, in addition to the above described
basic embodiment, means Eor engagement between the
cartridge and the bonnet.
The improvement due to this embodiment resides, as
noted above, in the fact that the cartridge 10 can be taken
out at the same time as the removal of the bonnet. This is
realized by providing two projections 62, 62 at the lower
25 part of the bonnet, as well as groove 17 on the inner
surface of the cartridge ll, which groove engages with
the projections, and passageS18 which permit the projec-
tions to enter into the groove.
For the purpose of re-assembling the valve after
inspection, repair or replacement of parts, subsequent
to placing the cartridge 10 in the valve body 2, the bonnet
6 and the bonnet stem 7 are placed on the body.
The bonnet should come down in such relative positions
to the body, as shown in Fig. 12A, ~hat the projections
62, 62 pass the passages 18, 1~ The bonnet is turned
90 horizontally, and then the projections 62, 62
engage with the groove 17 so that the bonnet 6 and the
cartridge 10 may be incorporated with a packing there-
between. By turning the bolts 61, to fasten the
bonnet, assembly of the valve is completed.
When it is desired to detach the cartridge 10 for
further inspection or repair, the fastening bolts 61, ...
are loosened, and the bonnet is llfted up. Then, the
cartridge 10 which is incorporated with the bonnet is
automatically taken out from the valve body 2, as shown
in Fig. 12B. Thus, the two steps of removing the bonnet
and detaching the cartridge can be carried out in one ~
ion.
2~ Needless to say, at the assembly of the valve, the
cartridge 10 may be previously incorporated with the bonnet
outside the valve body, and placed in the valve body
through a procedure reverse to the above described with
reference to Fig. 12B, to assemble the valve. This will
be desirable if the work near a pipe line must be
within/ space of~
done f~~ short~time. The present embodiment can be con-
sidered to enable not only the prompt detaching but also
the prompt attaching of the cartridge.
11
s~
The example shown in the Figures has the projections
on the bonnet and ~he groove on the inner surface of the
cartridge. Alternative arrangernents may, of course, be
practiced; i.e., a groove on the outer surface of the lower
part of the bonnet and projections on the inner surface of
the cartridge. The number of projections may,
be/
depending on the necessity, fncreased to three, four or
more. The angle of horizontal turn of the bonnet may
be less than 90 so long as the engagement between the
projection and groove is assured.
Like the basic embodiment, this preferred embodiment
can be applied not only to ball valves but also to valves
of other types such as gate valves, check valves and
globe valves.
As noted above, a valve according to the present
invention enables very quick inspection and repair by
detaching the car'ridge and, if necessary, replacing it
with a spare cartridge. It is easy to visually inspect
the parts in the cartridge detached from the valve body,
and to find the cause of any trouble. The box-type
valve body remains in place connected to the line pipe,
and therefore, the inspection and repair of the valve
exertin~
can be conducted without ~any influence on the pipe
line system.
i2
The present invention exhibits its greatest merits
when applied to cases where liquid spillage or contamination
of the human body or clothes must be avoided during
servicing. This is becuase the amount of li~uid remaining
in the valve is much less than that of the conventional
valves due to the difference in construction and~ moreover,
the remaining liquid is held in the cartididge case and
can be easily poured to a vessel for disposal.
Particularly, in the ball valves to which the present
i~vention is applied, the liquid remaining in the valve
can be kept in the passageway of the ball if the cartridge
is detached in the valve "closed'i state.
The handling of the valve can be conducted without
direct contact with the liquid, if the valve construction is
according to the preferred embodiment, or, even in the basic
embodiment, if the device for holding the cartridge is used.
If the liquid in the line pipe remains in the box
of the valve body and removal of the liquid is desired,
it is recommended to provide the valve body with a draining
nozzle at the bottom of the body.
Those skilled in the art could make other modification
and addition to the above described invention.
The valve of the present invention is the most
suitable when used in plants handling radioactive substances
25 as first mentioned. It is also valuable for application
in other fields of technology.
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