Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
A ~
In many situations one has need of being able to
shut off a pressure conduit or hose at conduit breaks,
This may be the case for instance with regard to gas
conduits or pressure oil concluits. One has therefore
developed various types of conduit-break valves, As
examples of some such valves mention may be made of
the published European patent application 79850114.4
~Publ~ No~ EP .~1-0 013 264j and the two published W2St
German patent applications DE-Al-28 23 262 and 29 28 529.
Co~mon to all of these valve mechanisms is that they com-
prise a val~e member which is movable in a valve housing
between an open position and a closed position prevent-
ing throughflow through the valve and which is yielding
ly urged towards its closed position and adapted to be
actuated in response to a pressure medium in the space
between the two conduits or hoses. In EP-Al-0 013 264
a break of the inner hose results in an increase of
the pressure in the space between the two hoses such
that a release mechanism rapidly relieves the pressure
between the two hoses, whereby a valve spring closes
the valve member. In the mechanisms according to
DE~A1-28 23 262 and DE-Al-29 28 52g a break of the inner
hose will result in an increase of the pressure in the
space between the two hoses such that this increased
pressure moves a piston device connected to the valve
member to closed position, This device is dependent
on a differential pressure being allowed to act against
differently large surfaces of r~ction, A damage to
~.~
6~5~3
the outer hose does not however lead to a closure of
the valve mechanism, The same is true of the mechanism
according to DE-Al-29 23 262.
This invention has for its objec-t to provide a
conduit-break valve which can be employed not only for
transporting media under high pressure but also such
media as gases under a relatively low pressure but will
still ensure shut-of of the main conduit upon a break
of the pressure conduit or hose or of the protective
conduit or hose or of both the pressure conduit and
the protective conduit or hose.
The invention thus relates to a conduit-break valve
of the type defined in the introductionl and the valve
is characterised in that it is adapted to operate under
a higher pressure in the space between the two conduits
or hoses than that prevailing in the pressure conduit
or hose and than that of the ambient atmosphere, and
that the valve member is connected to a piston or dia~
phragm device, the piston or diaphragm of which defines
a pressure chamber communicating with the space between .
the two conduits or hoses and is adapted normally to
maintain the valve mem~er in its open position.
A conduit-break valve designed in this way possesses
the desired properties. In certain cases, an insigni-
ficant leakage of the pressure conduit or hose or of
the protective conduit or hose may however result in
too slow a closing procedure or course~ In a further
development of the invention, the conduit-break val~e
therefore comprises a sensing and pressure relief mecha-
nism which is adapted to sense the position of the mainvalve member and, upon displacement of the main valve
member from its open position towards its closed posi-
tion, to relieve the pressure in the pressure chamber
such that the valve member is rapidly closed by the
action of the yieldable loading of the valve member~
The yieldable loading can be attained with the aid of
a pressure spring which acts against the piston or dia-
phragm device.
According to the invention, it is particularly
advantageous if the sensing and pressure relief mecha-
nism is formed as a mechanical relief valve having a
valve member whi.~h is urged towards its closed position
and has a valve rod adapted to be actuated by the valve
member of the conduit-break valve and to unseat the
valve member of the relief valve, thus opening the re-
lief valve for relief of the pressure in the pressure
chamber,
The invention will be described more in detail
in the following, refer~nce being had to the ~ccompanying
drawings which illustrate three embodiments of the valve
according to the invention. In the drawings:
Figs. 1 and 2 show an embodiment of the conduit
break valve in two different positions;
Figs~ 3 and 4 illustrate in the same manner another
embodiment of the ccnduit-break valve according to the
invention; and
Figs~ 5 and ~ illustrate a third embo~iment of
the conduit-break valve in two se~ting positionsO
The conduit-break valve shown in Figs~ 1 and 2
is adapted for conn~ction with a double conduit com-
prising an inner pressure conduit or hose 10 and an
outer protective conduit or hose 11, In the embodiment
illustrated these components are hoses with connecting
nipples for connection to a valve housing 12. The valve
housing 12 has an outlet 13 and an inlet 14 and an inner
valve seat 15. The connecting nipple of the pressure
hose 10 projects into the inlet 14 and seals against
the wall thereof. In the valve housing there is provided
a valve body or member 16 which is supported by a valve
rod 17. The rod 17 in turn is attached to a diaphragm
holder 18 which protrudes with a guide pin 19 through
a spring housing 20. The spring housing 20 is mounted
on the valve housing 12 and clamps a diaphragm 21 along
the edges of said diaphragm in order thereby to define
a pressure chamber 22 in the valve housing. At the bot-
tom of the pressure chamber 22 there is a guiding and
sealing device 23 through which the valve rod 17 extends~
A pressure spriny 24 is interposed between the spring
housing 20 and the diaphragm holder 18 and thus urges
the valve member 16 towards closed position ~Fig~ 2).
In the valve housing 12 there is also provided
a passage 25 which connects the pressure chamber 22
to the space 26 between the two hoses 10~ 11. The
conduit break valve accordlng to FigsO 1 and 2 operates
as follows: When the conduit-break valve is to be put
in operation, one increases the pressure in the space
~4~ 5~
26 between the two hoses 10, 11 to so high a pressure
above atmospheric that the diaphragm is moved upwards
to the position shown in Fig. 1, the pressure spring
24 being compresseds The pressure i.n the space 2~ and
the pressure chamber 22 shall thus be higher than both
the ambient pressure and the pressure prevailing in
the pressure hose 10. A break of the pressure hose or
inner hose 10 results in that the pressure prevailing
in the space 26 and 'he pressure chamber 22 is relieved
into the pressure hose 10. In a similar manner a relief
of the pressure prevailing in the space 26 is obtained
to the ambient atmopshere, if a break should occur on
the conduit 11. Upon relief o~ the pressure prevailing
in the space 26 and the pressure chamber 22 the pressure
spring 24 will successively move the valve member 16
downwards until the valve member seals against its seat
15 and thus shuts off the valve and thus the transport
of medium through the val~e,
The embodiment according to Figs. 1 and 2 can be
employed for different types of media, such as liquids
and gases. It is particularly suited for gases.
The valve according to Figs. 1 and 2 is so designed
that a small hole in the inner or outer hoses or inner
or outer conduits 10, 11 will result in a slow pressure
reduction in the pressure chamber 22 and, consequently,
ln a slow shut~off procedure. The embodiment accord-
ing ~o Figs. 3 and 4 gives a more rapid shut-off pro-
cedure. In Figs. 3 and 4 the same reference numerals
have been employed as in Figs. 1 and 2 to facilitate
a comparison.
The embodiment according to Figs~ 3 and 4 differs
from that according to Figs. 1 and 2 mainly by the de-
sign of the spring housing 20 and the components mounted
thereon. The device according to Figs. 3 and 4 thus
has a passage ~7 whLch is connected to the passage 25
o~ the valve housing and leads to a pressure gauge 28
and to further passages 29, 30 in the spring housing
20. The diaphragm holder 18 in this embodiment is de-
signed as a valve cone or member 31 with an O-seal 32
inserted in the sealing surface to seal against a valve
seat 33 surrounding the passage 30. The space 34 in
which the spring 24 is arranged, is in communication
with the ambient atmo~.phere through a vent hole 3~5~
The device further comprises a shut-off valve 36 wi~h
a ~alve member 37 sealing against the edge of the mouth
of the passage 29~ The spring housing 20 besides has
a filling nipple 38 which is connected to the passages
27 and 29.
Th~ function of the device according to Figs. 3
and 4 is as follows. When the device is to be put in
operation the valve 36 is closed and the pressure in
the space 26 between the hoses 10, 11 and in the passages
25~ 27 t 29 and the pressure chamber 22 is raised by
pressure fluid bei.ng supplied through th~. filling nipple
38 which may be designed as a check valve~ At.this rise
of pressure in int,al. the pressure chamber 22 the
spring 24 will be compressed to such an extent that
i 1~9 ~SO
the valve 31~ 32l 33 is closed. The expulsion of ~he
air in the chamber 34 takes place through the vent hole
35.~After that, the valve 36 is opened to the position
shown in the Figures.
If the conduit-break valve according to this embodi-
ment is employed for example for propane gas one usually
has a pressure of say 0,03 Bar in the inner hose 10,
and with this pressure it may be sufficient to use a
pressure of 0.15 Bar in the space 26 between the hoses,
As long as the hoses 10, 11 are intact the conduit-break
valve remains in the state shown in Fig. 3~ Should a
break occur on the inner or the outer hose or on both
hoses 10, 11 the pressure will sink in the chamber 22
so that the diaphragm holder 18 begins to move to the
left as seen in FigO 3~ As soon as this movement is
initiated, the ~alve formed by the components 31~33
will be opened so that a free passage from the space
26 to the ambient atmosphere is immediately attained
via the passayes 25, 27, 29, 30, the chamber 34 and
the vent hole 35. This leads to an instantaneous closure
of the valve 15~ 16 by the action of the pressure spring
~4.
The pressure gauge 28 in the embodiment according
to Figs. 3 and 4 can be used to watch that the excess
pressure in khe space ~6 between the two hoses 101 11
lies within the suitable range. Too low a pressure,
say in the vicinity of 0.10 Bar, leads to a great risk
o~ unintentional quick release of the valve, and too
high a pressure may be unsuitable with regard to the
conduit and hose equipment~
The quick release valve 31-33 in the embodiment
accordiny to Figs. 3 and 4 operates although the same
pre~sure prevails in the chamber 22 as that in the pas~
sage 30. The pressure force taken up by the lar~e area
of the diaphragm thus is greater than the total pressure
force of the spring 24 and the pressure acting upon
the small free area opposite the passage 30.
As shown in Figs. 5 and 6, the conduit-break valve
according to the invention can be provided with a piston
device instead of a diaphragm deviceO This embodiment
of the invention is paxticularly suited for say oil
conduits where one operates with higher pressures or
for media which might damage the diaphragm in the two
embodiments described in the foregoing,
The conduit-break va1ve shown in Figs~ 5 and 6
has a valve housing 40 with an inlet 41, an outlet 42
and a connecting passage 43. In the valve housing there
is provided a valve seat 44 for a valve cone or member
.
450 The valve cone 45 has a valve rod 46 which is guided
in a guiding and sealing device 47~ Said guiding and
sealing device 47 forms one end wall of a pressure cham-
ber 48, the other end wall of which is formed by a pis-
ton 49 which is fixedly mounted on the valve rod 46
and suitably sealed against the wall of the pressure
chamber 4~, The piston 49 is under the action of a pres-
sure spring 50 in a spriny housing 5L~
~3 ~t~
From the pressure chamber 48 leads a passage 52
which is connected in a suitable manner to a space 53
between an inner pressure conduit 54 and an outer pro~
tective conduit 55. These conduits are mounted in a
suitable way on the valve housing 40, the nipple 56
of the pressure conduit 54 sealing against the wall
of the outlet 42 of the valve housing 4D.
Same as in the embodiment according to Figs. 3
and 4 there is provided a sensing and pressure relief
mechanism which is intended rapidly to relieve the pres-
sure in the pressure chamber 48, should a break occur
on the inner or outer conduit 54, 55~ In this case use
is made of a mechanical relief valve which has a valve
rod 57 and valve ball or member 58 which is normally
urged by a pressure spring 5g into sealing engagement
with a seat 6~ When the valve ball 58 is in engagement
with the seat 60 the connection between the pressure
chamber 48 and a collecting chamber 61 is broken. This
connection is established via the passage 52 and a pas-
sage 62 in the valve housing 40 as well as a passage
63 in a valve housing 64 in which the quick release
valve is provided. In said valve housing 64 there are
also provided passages 65 and 66 which lead to the col-
lecting chamber 61. In the transition between the chan- -
nel 65 and 66 there is disposed a shut-off valve 67,
in the form of a needle valve, which acts against the
mouth of the passage 65~
In the valve mechanism according to Figs~ 5 and
6 the pressure in the space 53 between the hoses 54
1~
~nd 55 is raised with the aid of a filling device 68
~t the other end of the conduits or hoses 54 t S5.
The mechanism shown in Figs~ 5 and 6 operates in
the following manner.
When the mechanism is to be put in operation the
needle valve 67 is screwed into engagement with the
mouth of the passage 65. Then the pressure in the system
is raised by a pressure medium being supplied through
the valve mechanism 68. As a result~ the piston 49 will
be moved upwards to the position shown in Fig. 5, the
spring 50 being compressed. At the same time the valve
ball 58 and the valve rod 57 will be moved upwards to
the position shown in Fig. 5 as the valve member 45
moves upwards together with the piston 49. After the
prescribed excess pressure has been established in the
space 53 and the passages communicating therewith, the
neddle valve 67 is opened so that the passages 65, 66
are interconnected~ If there should now arise a break
of the outer hose 55 the pressure will sink in the space
53. Cvrrespondingly, the pressure will sink in this
space if the inner hose should break. For the valve
ls designed to have a higher pressure in the space 53
than that prevailing in the hose or conduit 54. At a
pressure reduction in the space S3 the piston 49 will
be pressed downwards by the spring 50, At the same time
the valve member 45 will actuate the valve rod 57, thus
unseating the ball 58 from its seat 60. There now occurs
an instantaneous relle~ of the pressure in the space
11
~L 1.9 ~6-.~0
53 by the pressure medium flowing through the passages
62, Ç3, 67 and 66 to the collecting container 61. At
-this instantaneous relief the pressure spring will ra-
pidly move the valve member 45 down towards its seat
44 so that the valve is closed.
The embodiments of the invention described above
are only meant as examples, and many variations are
possible within the scope of the appended claims~
