SK87495A3 - Safety shut-off for gas lines - Google Patents

Abstract

The problem underlying the present invention is that of providing a safety shut-off for gas lines in which the valve body bed is frictionless and maintenance-free and which presents only a minimum flow resistance. In addition, the safety shut-off is to do without any outside seal. It is to be easily fitted and capable of installation in existing gas lines without fittings or any alteration thereto. The problem is solved in that, in a safety shut-off for gas lines with a valve body (6) which can be pressed against a valve seat (1), in which the valve body (6) is fitted to be movable in the axial direction of the valve seat (1) against the force of a closing spring, the valve body is guided only by a spring and is otherwise free to move without any additional seating. The invention relates to a safety shut-off to close gas lines in the event of damage, e.g. pipe breakages or tears in hoses, to prevent the uncontrolled escape of gas and hence avoid any danger.

Description

Safety valve for gas dilution.

Area, techniques

The invention relates to a gas line safety valve with valve and valve seat according to the feature of the first claim.

The safety closures thus designed serve to close the gas line in the event of accidents, for example, in the event of a pipe rupture or hose breakage, in order to prevent uncontrolled gas leakage and the resulting danger.

BACKGROUND OF THE INVENTION

Safety closures are known which are placed between the gas distribution and the conduit to the appliance and which should ensure the shut-off of the inlet, for example, in the event of a pipe rupture or hose breakage.

Thus, it is known from U.S. Pat. No. 4,830,046 according to which a safety closure having a thread at both ends thereof has a spherically shaped valve which is pushable against the opposite valve seat, the valve being displaceable up to the spring pressure of the valve seat to the closed position. When the valve is in the open position due to spring pressure, it rests against the seat and is guided only by this spring when moving to the closed position.

This solution has the advantage that both the screwed-in element serving as the valve seat in the open position and the second screwed-in element serving as the coil spring adjustment holder cause additional pressure loss of the flowing gas. To avoid these losses and ensure the desired flow rate, large volume closures must be purchased. A further disadvantage is that two new sealing points are added, and also when the safety closure is combined with other fittings, such as a hose tap, they increase the time required to build the conduit. When retrofitting the shutters, the gas line must also be shortened to the required length.

Because of the need for threading for connection, there is also a need for a corresponding device.

A further safety closure is disclosed in the invention of WO 92/01184, according to which a safety closure closes the conduit in the event of damage to the conduit of the appliance, but without prior closure of the gas distribution, even if the appliance consumes more gas corresponding to its full output. . In these safety closures, the valve is movable in the direction of the axis of the tube-shaped cavity, has a plate-like shape and is displaceably mounted so that the spring force acts against it. Disc valve bearing discs are housed in a cavity in a central position and have vents on their periphery through which gas flows. The closure body has threads at both end ends for connection to a pipe conduit or other fittings.

One of the drawbacks of this solution is that the movement of the disk valve takes place in the guide bearing. The compressive forces that cause movement to the closed position in the event of an accident must overcome, the resistance of the spring, which sets the closing flow rate, and only a few millibars of the compressive force are available to move the safety valve. Each friction in the guide bearing distorts the valve closing flow rate and does not reproduce it.

This drawback is particularly poor in cases where the valve is idle for a long time in normal operation and therefore no movement of the valve shaft in the bearing takes place, so that impurities from the flowing gas are deposited thereon. The use of safety closures is envisaged, inter alia, for gas lines which are buried in the ground, which means that they have to perform their safety function over a long period of time, for example several decades, without maintenance.

A further drawback is that by incorporating such a valve into the gas line, two new points need to be sealed when combining a safety valve with another valve, such as a hose tap, to extend the time required to build the line. When retrofitting the cap to an existing plant, the gas line must be shortened accordingly.

The breather disks, which serve to guide the disk valve in the bearing, create an additional pressure loss. Due to the connecting threads and the overall assembly, this solution also appears to be a costly device.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problem in order to achieve a gas line safety shut-off in which a convenient, maintenance-free and friction-free valve housing is to be maintained and which imposes minimal resistance to the gas flow. Furthermore, the security closure should be connected to the gas line without further sealed joints. It should be easy to install and can be used without modification for all common gas lines and fittings.

According to the invention, the problem is solved in that the valve body is guided only by a spring and is in the form of a freely movable plate supported in an open position in the axial direction against a resilient seat mounted in a groove formed directly into the valve seat body. For an extremely low weight, this solution has the particular advantage that the dependence of the location of the added mass, which, for example, can affect the pipeline balance and the distribution of forces and thus the closure closure, has very little effect.

Advantageous extensions of the invention come from further claims.

In this case, it can be designed as a spring strut or as a cut ring, which has in particular three equally spaced radially inwardly extending radially inwardly directed rings around the circumference, whereby the flow cross section is only slightly reduced.

In order to allow adjustment without changing the flow cross-section, it seems advantageous if the holder, by which the spring supporting the valve is adjusted in the axial direction, is connected to the valve seat by a thread, for example. This adjustable holder provides the possibility of adjusting the safety cap without changing the inflow cross-section.

Especially when used in conjunction with a conventional gas cock, it is preferable that the safety shutter is inserted into the inlet of the gas cock, wherein the valve plate of the safety shutter has an oval-shaped offset on its spring-side side in the axial direction. , but which, when the security closure is opened, is drawn into its interior. It is of course also possible if the valve seat as a whole together with the inlet of the gas cock is produced. In this case, the security closure is so deep in the inlet that the oval-shaped offset when the security closure is closed extends up to the pivoting region of the tap-cock. With this solution, the security closure can be completely sealed. A recess for the automatic re-opening of the safety cap is not required. By closing the gas cock, which must always be done when removing an accident, for example when replacing a hose, the oval shaped offset moves in the direction of the axis, thus reopening the safety cap so that the gas can flow again after the cause of the accident is removed.

In another embodiment, it is preferred that the outside diameter of the valve without the resilient seal is less than the inside diameter of the associated valve seat, while the outside diameter of the valve with the seal mounted is larger than this inside diameter, the entire circumference of the protrusion beyond which the valve seat in the flow direction continues with the tubular shaped end portion, the length of which is so determined that the stopper does not exceed this tubular shaped end portion when the gasket is engaged and the safety cap is closed; so deep into the valve seat that the stop protrudes from the end portion, which is sufficient for the assembly to be simply carried out in such a way that the valve together with the spring is pushed so deep into the valve seat when the gasket is fitted can be mounted on a bolt having a valve formed in the flow direction. The gasket is then fitted.

It is advantageous if the bolt is provided with a thread, by means of which, for example, a wire-shaped stop is easily fixed and can be moved along the bolt in the axial direction for adjustment purposes.

Naturally, it is also possible to screw the valve onto a thread formed on the bolt in the direction of its axis, while the stop abutting on the projection is firmly connected to the bolt.

P-R-examples-of-a-to-toc-not-a

The invention will be described in more detail below with reference to the examples. The images show:

Fig. 1 is a cross-section of a safety shutter according to the invention intended for gas lines in the open position;

Fig. 2 is a cross-sectional view of the gas shut-off safety closure according to the invention, in the closed position;

Fig. 3 is a safety closure according to the invention intended for gas lines prior to the installation of a flexible seal;

Fig. 4 is a cross-sectional view of a safety shutter according to the invention intended for gas lines, in an open position, made in another manner,

Fig. 5 is a security closure according to the invention of FIG. 4, viewed from direction A,

Fig. 6 is a cross-sectional view of a safety shutter according to the invention intended for gas lines, in an open position, made in another manner, without a flexible seal;

Fig. 7 is a cross-sectional view of the safety shut-off according to the invention intended for gas lines, in the open position, made in another way with a floating valve (6),

Fig. 8 is a security closure according to the invention of FIG. 7, viewed from direction B,

Fig. 9 is a security closure according to the invention of FIG. 7, with the valve seat changed, seen from direction B,

Fig. 10 is a cross-section of an adjustable safety shutter according to the invention intended for gas lines, in an open position, made in another manner,

Fig. 11 is a safety shutter according to the invention intended for gas lines inserted into the gas cock inlet in the closed position;

Fig. 12 is a safety shutter according to the invention for gas ducts incorporated in the inlet of the gas cock in the open position forced by the cock position;

Fig. 13 is a safety closure according to the invention intended for gas lines, in the open position, inserted into an electrically welded sleeve,

Fig. 14 is a safety closure according to the invention intended for gas lines, in the closed position, incorporated into an electrically welded sleeve;

Fig. 15 is a valve seat suitable for execution in an electrically welded sleeve.

AM 4

In FIG. 1, the safety closure of the present invention for gas lines comprises a tubular valve seat 1 having an outer diameter smaller than the inner diameter of the gas line not shown in the drawings, a ring 26 having a diameter greater than the diameter of the gas line. 26. For easier and reliable pressing of the safety closure according to the invention into the gas conduit 26, the ring 2 is preferably provided with an insertion bevel 3. Further, it appears suitable if the valve seat 1 has circumferential grooves 4 on both sides of the ring 2 to achieve a higher ring 2 height. and thus better elasticity when pressed.

With respect to the direction of the arrow indicating the direction of flow, the seat has a sealing surface 5 in the form of a spherical recess. Inside the valve seat 1, a valve 6, which has an annular groove for receiving the seal pohybuje, is moved in the axial direction. In this case, the valve 6 and the gasket 7 are so designed that the outer diameter of the valve 6 without the gasket 7 is smaller than the associated inner diameter of the valve seat.

1, but the outer diameter of the valve 6 with the seal 1 installed is larger than this inner diameter.

On the outlet side with respect to the flow direction, the valve 6 has a spring 8, holding the valve 6 in an open position, which is primarily a compression spring and which at its other end bears on a circumferential projection 9 located on the inner diameter of the valve seat 1. associated with the valve 6.

The guiding of the spring 8 ensures the shoulder 10 of the valve 6, which in the flow direction flows into the bolt 11. At the end of the bolt 11 there is a transverse bore 12 which serves to secure the stop 13, in this case a pin (Fig. 1).

There is a relationship between the length of the bolt 11 and the length of the tubular end portion 14 located behind the protrusion 9 of the valve seat 1 such that the stop 13 does not leave the tubular end portion 14 when the gasket 2 is mounted and the safety closure (FIG. 2) is closed. however, in the absence of the seal 7, it is possible to push the valve 6 into the valve seat 1 so that the stop 13 protrudes from the end portion 14 (FIG. 3).

A slightly different embodiment is shown in FIG. 4. In this case, the bolt 11 is threaded, and as the stop 13 a wire clamp 15 is provided so that it can be screwed onto the bolt 11.

In FIG. 6, another embodiment is shown. This solution differs from the foregoing in that the valve 6 and the bolt 11 consist of two separable parts, the valve 6 having a thread with an inlet 16 in the axial direction, into which a threaded bolt 11 is screwed in the axial direction to which the stop is fixed. 13, supported by the protrusion 9 of the valve seat 1. Due to the necessary sealing and at the same time to prevent rotation, one of the conventional sealing means, such as e.g. in this case PTFE tape 17. In this version, elastic seals can be dispensed with. To achieve the desired tightness, the valve 6 is shaped as part of a spherical surface, while the sealing surface 2 on which it rests is shaped as an inclined surface. A recess 27 is provided on the valve to retain the spring 8 and simultaneously reduce weight.

In the further embodiment of the security closure of the invention shown in FIG. 7, the end of the valve seat 1 is reinforced to form a ring 2 and at the same time a bevel

3, which differs from the previously described embodiments. This shape of the valve seat 1 is particularly suitable for incorporation into the gas pipes of PE pipes, which is shown in FIG. 7 with the number 26. In this case, the safety closure is mounted such that, for example, the gas pipe 26 of the PE pipe is heated. The flexible piece in this case is not the ring 2, but the gas line 26.

The valve consists of a free-floating disk 18, retained only on the spring 8, which in the open position bears in a direction perpendicular to the axis on a resiliently deformable seat. The radius consists in this case of the embodiment shown in FIG. 8 very clearly, from a spring strut 20 which is engaged in a groove 19 recessed all over the inner circumference of the valve seat 1.

It will be understood that instead of the spring strut 20, other shaped shapes may be used. This is the case, for example, in the embodiment of FIG. 9, where a cut ring 24 is used which preferably has three circumferentially spaced, radially inwardly directed protrusions 25 on the circumference. In this embodiment, it is only necessary to consider whether the flow cross-section is reduced too much by the projections.

The required tightness is achieved by placing on the plate 18 a seal 7 which abuts against the spherically shaped sealing surface 5 of the valve seat 1.

In PE gas pipes, where the most common buried pipes are and where the safety lock is hardly accessible, the plate 18 has a recess 23 which is accessible from a defined and, of course, accessible construction breaks in order to eliminate the cause of the accident. led to the closure of the security closure, had it reopened.

In FIG. 10 is a security closure just described according to FIG. 7, but so arranged that the holder 21 is a separate part connected to the valve seat 1 by means of a thread 22 and thus adjustable in the direction of the axis. In this way, an adjustment that does not cause a change in flow cross-section is possible.

An embodiment of the security closure of the invention associated with a commonly used gas cock 29 is shown in FIG. 11 and 12. 11 is a safety closure fitted to the inlet of the gas cock 29; FIG. 12, the valve seat 1 is directly a part of the inlet of the gas cock 29. In both embodiments, the safety valve plate 18 has an oval-shaped offset 2.8 on its spring-side 8 in the axial direction, which protrudes therefrom when the safety valve is closed (FIG. 11). this is in the open position of the security closure inside. In this case, the safety shut-off is so deeply inserted into the cock inlet that the oval-shaped offset 28 is located in the region of rotation of the shut-off valve 32 of the gas cock 29 when the safety valve is closed. the end is correspondingly shaped to be displaced in the direction of the axis (FIG. 12), whereby the safety closure is fully opened again by the action of the spring 8. Thus, after the accident has been removed and the gas cock 29 has been opened, the gas can flow again.

In the gas conduits 26 consisting of PE pipes, the so-called electrically welded sleeves 30 are in many cases used as connecting means. An embodiment of the safety closure advantageous for this case is shown in Figures 13 and 14. 13 is a safety closure fitted to the electrically welded sleeve 30. FIG. 14, the valve seat 1 is directly a part thereof. In order to make it easy to realize the plate seat 33, the plate has the form of a ring 24, which is shown in FIG. 9, but in addition to the protrusions 25, on its outer periphery, it has teeth 34 (FIG. 15) which are pushed into the electrically welded sleeve 30.

As can be seen from both figures, the inner diameter of the security closure can be increased if it is outside the gas conduit 26, thereby minimizing the gas pressure losses caused by the security closure.

In order to keep the extension of the conduit construction time, which is increased by the welding device at both ends of the gas conduit 26, is preferably provided with a safety closure at its outlet end whose flow cross section is larger than the flow cross section of the plate area. a shoulder 31, the outer diameter of the shoulder 31 being smaller than the inner diameter of the gas conduit 26.

It is understood that the individual embodiments described in this section do not claim to be considered to be specially highlighted

- 10 or completely final. It is therefore possible, for example, for the individual parts of said embodiments to be exchanged (combined) with one another without leaving the area of protection claimed.

Claims (7)

Patent claims A gas line safety shutter having a valve (6) pushable into an opposite valve seat (1), wherein the valve (6), which is guided only by the spring (8) and thus without additional guidance, is freely movable and which is in the direction of the axis a valve seat (1) movable to the closed position against the force of the spring (8), characterized in that the valve (1) has a free-floating disc (18) on the spring (8) which is supported in the open position in the radial direction the seat is retained in the groove (19), which is in particular part of the valve seat and thus indivisibly connected to it. A gas seal according to claim 1, characterized as a spring strut (20). The gas-line safety closure according to claim 1, characterized in that the base is an embodiment according to claim 1, characterized in that the base is formed as a cut ring (24) having in particular three equally spaced, radially inwardly directed projections (25) circumferentially. . Gas line safety closure according to one of Claims 1 to 3, characterized in that the holder (21) of the remote end of the spring (8) into the valve (6) is adjustable in the axial direction by being fixed to the valve seat (8). 1) in particular by means of a thread (22). Gas-line safety closure according to one of Claims 1 to 4, characterized in that the plate (18) has an oval-shaped offset (28) in its axially-oriented direction on its spring-side side (8) which, when the safety closure is closed it is inserted into its interior. The gas line safety closure according to claim 5, characterized in that the valve seat (1) and the inlet part of a conventional gas valve (29) are made in one piece and thus indivisibly connected. for gas lines according to the patent on which the elastic seal (7) is, the seal (7) is a smaller valve seat (1), a fitted seal (7) is formed on this circumferentially (8) against the valve stop 6) the diameter of the valve (6) without its associated outside diameter of the valve (6) with the diameter, seat (1) of the projection spring (9) by the bolt (11) as this inner diameter of the valve (9) The security closure of claim 1, wherein the outside diameter is greater than the internal flow projection (13), which is supported in the open position of the security closure, (1) behind the portion fitted with the gasket that the valve seat is shaped end stop (13). ) at (6) which passes through the outlet (14) of which (9) passes into a tubular length is thus determined (7) and in the closed position of the safety closure does not extend from this end part (7) the seat valve (1) ) that the stop (14), on the other hand, but in the absence of the seal (6), extends so deeply (13) from being pushed into the valve end portion (14). A gas seal according to claim 7, characterized in that it is configured as a wire clamp (15).