DE102022105939A1 - Knife gate valve, method of operation and use - Google Patents

Abstract

The invention relates to a knife gate valve (10) for chemical and/or petrochemical industrial plants, comprising: - a valve housing (11) which has an inlet connection (12) with an outlet opening (13) and an outlet connection (14) with an inlet opening (15). , which correspond to one another when the knife gate valve (10) is in an open position; 12, 14) is movably arranged; and- at least one guiding device (19) for guiding the flow, the guiding device (19) having at least one guiding element (21) which is arranged on an inner wall (22) of the inlet connection (12) and the outlet opening (13) of the inlet connection (12) reduced in such a way that when the knife gate valve (10) opens, an opening cross section (23) of the outlet opening (13) is enlarged at the moment of an initial, in particular first, flow entry into the pipe bridge (18).

Description

The invention relates to a knife gate valve, a method for operating a knife gate valve and the use of a knife gate valve. A knife gate valve according to the preamble of patent claim 1 is made, for example DE 10 2016 111 169 A1 known.

In general, high demands are placed on the tightness and longevity of slide valves that are used, for example, in a coking and/or cracking process. In addition to liquids or gases, the pressurized fluid conducted through such slide valves can also contain solids, for example very small particles, such as impurities, dust, soot and residues, for example from a coking process or a cracking process.

Slide valves of this type are often designed as plate slides, with single plate slides or double plate slides being used predominantly. Double plate slides, the basic principle of which goes back to a technology developed by the applicant, have proven particularly useful for use in ethylene plants. In such knife gate valves, the slide plates in the shut-off position are pushed apart by a spreader element arranged between them, specifically a wedge-in-wedge arrangement, when a slide rod connected to the spreader element is actuated and pressed against the corresponding housing sealing seats to improve the sealing effect. Such a plate valve is out EP 0 450 646 A2 known to the applicant.

A particular problem with such knife gate valves has been found to be the erosion of the housing sealing seats by the particles contained in the fluid flowing through. In the initial phase of the opening process of the knife gate valve, a punctiform passage is created, which forms a fluid flow at very high speed due to the pressurized fluid. Due to the particles it contains, this fluid flow causes severe signs of erosion on the housing sealing seats, especially on the housing sealing seat of the outlet connection of the slide. As a result, the sealing effect deteriorates during the service life of the knife gate valve, so that the maintenance effort increases and the service life of the knife gate valve is shortened.

In order to counteract the erosion of the housing sealing seats, a knife gate valve was developed, for example, which uses a baffle plate to deflect the fluid flow with the particles it contains in such a way that, particularly in the initial phase of the opening process, in which there is a very high flow speed due to the punctiform opening cross section, a direct flow to the outlet-side housing sealing seat is prevented. Such a plate slide is, for example, from the aforementioned DE 10 2016 111 169 A1 known.

The plate slider off DE 10 2016 111 169 A1 however, has the disadvantage that the baffle plate is subjected to high abrasion loads by the fluid flow containing particles. Furthermore, due to the deflection, the baffle plate causes increased turbulence of the fluid flow in the knife gate valve, so that a pressure loss through the knife gate valve is increased and other components of the knife gate valve are subjected to abrasive loads due to the flow deflection.

The invention is based on the object of specifying an improved knife gate valve which has an increased service life and increased resistance to erosion. Furthermore, the invention is based on the object of specifying a method for operating a knife gate valve and the use of a knife gate valve.

According to the invention, this object is achieved with regard to the knife gate valve by the subject matter of claim 1 or 17. With regard to the method, the above object is achieved by the subject matter of claim 20 or 22. With regard to the use, the above-mentioned object is achieved by the subject matter of claim 23.

• - ein Schiebergehäuse, das einen Einlassstutzen mit einer Ausgangsöffnung und einen Auslassstutzen mit einer Eingangsöffnung aufweist, die in einer Offenstellung des Plattenschiebers miteinander korrespondieren;
• - eine Sperreinrichtung mit wenigstens einer Absperrplatte und einer Rohrbrücke, die zum Öffnen und Schließen des Plattenschiebers zwischen dem Ein- und Auslassstutzen beweglich angeordnet ist; und
• - wenigstens eine Leiteinrichtung zur Strömungsleitung.

Erfindungsgemäß weist die Leiteinrichtung wenigstens ein Leitelement auf, das an einer Innenwand des Einlassstutzens angeordnet ist und die Ausgangsöffnung des Einlassstutzens derart verkleinert, dass beim Öffnen des Plattenschiebers ein Öffnungsquerschnitt der Ausgangsöffnung im Moment eines anfänglichen, insbesondere ersten, Strömungseintritts in die Rohrbrücke vergrößert ist.Specifically, the task is performed by a knife gate valve for chemical and/or petrochemical industrial plants, including:

• - A slide housing, which has an inlet connection with an outlet opening and an outlet connection with an inlet opening, which correspond to one another in an open position of the plate slide;
• - A locking device with at least one shut-off plate and a pipe bridge, which is movably arranged to open and close the plate slide between the inlet and outlet; and
• - At least one guiding device for the flow line.

According to the invention, the guide device has at least one guide element, which is arranged on an inner wall of the inlet connection and reduces the outlet opening of the inlet connection in such a way that when the knife gate valve opens, an opening cross section of the outlet opening is enlarged at the moment of an initial, in particular first, flow entry into the pipe bridge.

The fluid stream includes process media such as steam and/or hydrocarbons. The inlet socket can also be referred to as the inlet flange and the outlet socket as the outlet flange.

The invention has the advantage that when the knife gate valve is opened at the moment of the first flow entry, ie at the moment when a passage opening is formed, the flow velocity of an inflowing fluid stream mixed with particles is reduced by the enlarged opening cross section from the inlet connection into the pipe bridge. In contrast to the knife gate valve DE 10 2016 111 169 A1 According to the invention, an enlarged opening cross-section is provided at the exit opening of the inlet connection in the pipe bridge at the moment of opening. As a result, the fluid flows into the pipe bridge at the opening moment, distributed over a comparatively larger opening cross section. This has the advantage that a nozzle effect, such as that in the knife gate valve according to DE 10 2016 111 169 A1 present, reduced or even prevented. As a result, for example, a housing sealing seat, which is arranged opposite the opening cross section of the outlet opening of the inlet connection in the direction of flow, or a housing sealing seat on the outlet side, is protected from a selective inflow by the fluid flow laden with particles. Erosion of the housing sealing seat is thus prevented or at least greatly reduced, so that the knife gate valve has increased functional reliability and a longer service life.

The guide element reduces the outlet opening of the inlet connection in such a way that the opening cross section of the outlet opening is enlarged at the moment when the flow first enters the pipe bridge. In other words, the guide element protrudes into the exit opening in order to reduce the exit opening. In other words, the guide element delimits the exit opening so that it is reduced. The guiding element can reduce the outlet opening of the inlet connection piece by up to 10 percent, in particular by up to 7 percent. The guide element preferably reduces the outlet opening of the inlet connection piece by up to 5 percent. In order to increase the cross section of the opening, the guide element has a certain shape, which is preferably approximated to an inner contour of the pipe bridge. This means that the guide element on the one hand narrows the outlet opening due to its extension transversely to a longitudinal direction of the inlet connection and on the other hand increases the opening cross section of the outlet opening in the pipe bridge in the opening phase due to its shape.

The guide element is preferably designed in such a way that at the moment of the first flow entry from the inlet connection piece into the pipe bridge, the opening cross section of the outlet opening of the inlet connection piece forms a cross-sectional shape that deviates from a punctiform cross section. This corresponds, for example, to the enlarged opening cross section. The opening cross section preferably has at least one passage area at the moment of the first flow entry from the inlet connection piece into the pipe bridge. The opening cross-section here has a greater extent than a punctiform opening. Particularly preferably, the opening cross section forms at least one gap at the moment of the first flow entry from the inlet connection piece into the pipe bridge. The gap is preferably arcuate in sections. In other words, the gap is preferably in the form of a segment of a circle. Alternatively or additionally, the gap can be linear, at least in sections. Alternatively or additionally, the opening cross section can be linear at the moment of the first flow entry from the inlet connector into the pipe bridge. Other geometries of the opening cross section are possible.

At the position of the outlet opening of the inlet connection, the guiding element preferably has a shape adapted to an inner contour, in particular an inner circumference, of the pipe bridge in order to enlarge the opening cross section.

The opening cross section is limited at the moment and during the entire opening process by a contour of the inner wall of the inlet connection, the guide element and the pipe bridge, in particular an inner contour of the pipe bridge. In other words, a contour of the inner wall of the inlet socket, the guide element and the pipe bridge define the size of the opening cross section of the outlet opening of the inlet socket when the knife gate valve is opened and closed.

The shape of the guide element, which preferably approximates the inner contour of the pipe bridge, is one way of enlarging the opening cross section of the outlet opening of the inlet connector. A further possibility for enlarging the opening cross section consists in designing an outer contour of the guide element with a straight outer edge. The outer edge preferably extends transversely to the opening and closing direction of the plate slide. In general, the shape of the guide element, specifically the outer edge of the guide element, differs from the shape of the inner wall of the inlet connection.

The shape of the guide element, specifically the outer edge of the guide element, deviates from the shape of the inner wall of the inlet connection in such a way that a nozzle-shaped opening cross-section of the outlet opening of the inlet connection of the knife gate valve is avoided or at least occurs more quickly than in the Prior art is repealed, which arises in the prior art when the pipe bridge and the inlet nozzle overlap due to the respective opposite curvatures of the inner walls. A nozzle-shaped, punctiform opening cross section is avoided if, for example, the guide element, specifically the outer edge of the guide element, and the pipe bridge have the same radii of curvature, which lead to a linear opening cross section. A nozzle-shaped, punctiform opening cross-section is eliminated more quickly than in the prior art if, for example, the guide element, specifically the outer edge of the guide element, is straight, since the opening cross-section then increases more quickly than in the prior art.

In general, the initial onset of flow is delayed compared to the prior art. The time delay means that the opening cross section can be enlarged in the initial opening phase until an effective flow passage begins without the harmful nozzle effect occurring. The nozzle effect is at least reduced.

The time delay in the opening of the inlet connector has the further effect that the outlet connector is opened further relative to the inlet connector at the same point in time. The opening cross section of the outlet connector is therefore larger than the opening cross section of the inlet connector at the same point in time.

The invention thus has two effects. The guide element prevents the formation of a nozzle-shaped "punctiform" opening at the inlet connection or enlarges the opening more quickly than in the prior art. At the outlet connection, the invention results in the opening cross section of the outlet connection being larger than the opening cross section of the inlet connection at the same time, because the guiding element delays the opening of the inlet connection. The outlet port is more open relative to the inlet port at the same time.

In both cases, i.e. with a straight or curved outer edge, or generally in connection with the invention, the guide element, specifically the outer edge of the guide element, is arranged so close to the plane spanned by the outlet opening of the inlet connection that the guide element closes the outlet opening when the knife gate valve opens at least temporarily shields against the passage of the fluid flow. This avoids a fluid flow immediately passing through the outlet opening when it is opened and destroying the effect according to the invention. For the shielding effect, the guide element does not necessarily have to be directly adjacent to the plane or touch the blocking device. A small distance between the guide element, specifically its outer edge, and the plane is possible, provided that no significant fluid flow, e.g. due to turbulence, passes the guide element through the knife gate valve before the inner wall of the pipe bridge passes the guide element, specifically its outer edge when opening has.

In other words, the guide element seals against the blocking device in such a way that the flow of fluid through the plate slide is delayed when it opens. The guide element has a temporary blocking function when the knife gate valve opens.

The guide element forms a stationary or fixed blocking element that acts temporarily when opening. The guide element is arranged in a stationary manner on the inlet connection. In contrast, the locking device is movable.

The blocking device is movably arranged between the inlet and outlet connections. The blocking device is preferably arranged to be linearly movable between the inlet and outlet connections. In concrete terms, the blocking device can preferably be displaced between the open position and a closed position of the plate slide.

In the open position, the inlet socket and the outlet socket are connected to one another by the pipe bridge. In the closed position, the inlet connector and the outlet connector are blocked from one another by the at least one blocking plate.

When the plate slide is opened or closed, the blocking device is moved, preferably by a slide rod. The travel between the open position and the closed position corresponds to a total stroke of the blocking device, in particular the slide rod. In the closed position the blocking device is arranged in a minimum stroke position and in the open position the blocking device is arranged in a maximum stroke position. In other words, the blocking device has a stroke of 0 percent of the total stroke in the closed position and a stroke of 100 percent of the total stroke in the open position.

The stroke range in which the opening cross section of the outlet opening of the inlet connector influences an applied process pressure can include 0 percent up to 35 percent of the total stroke. This stroke range corresponds to the opening phase of the knife gate valve. The opening phase, in which the moment of the first flow entering through the outlet opening of the inlet connection piece into the pipe bridge, can take place with a stroke of the blocking device of 22 percent to 35 percent, in particular from 22 percent to 30 percent, of the total hubs. The moment of the first flow entry through the outlet opening of the inlet connection piece into the pipe bridge preferably takes place at a stroke of the blocking device of 23 percent to 28 percent, in particular of 24 percent to 26 percent of the total stroke. Particularly preferably, the moment of the first flow entry through the outlet opening of the inlet connection piece into the pipe bridge occurs at a lift of 25 percent of the total lift.

The outlet opening of the inlet connector and the inlet opening of the outlet connector preferably border on the blocking device. Housing sealing seats are preferably located at the position of the outlet opening and the inlet opening in order to cooperate with the blocking device for sealing.

The knife gate valve is particularly preferably designed as a double knife gate valve. In this case, the blocking device preferably has two blocking plates which are arranged concentrically in a plate cage. The shut-off plates or the pipe bridge preferably lie against housing sealing seats in the closed or open position.

Preferred embodiments of the invention are given in the subclaims.

In a preferred embodiment, the guide element is designed in such a way that when the knife gate valve is opened, the outlet opening of the inlet connection piece can be released with a delay in relation to the inlet opening of the outlet connection piece. During an opening process, the pipe bridge first intersects with the inlet opening of the outlet connection and then with the outlet opening of the inlet connection. The guide element therefore first opens up an opening cross section of the inlet opening of the outlet connection piece into the pipe bridge and then the opening cross section of the outlet opening of the inlet connection piece.

The outlet opening of the inlet connection and the inlet opening of the outlet connection are preferably arranged concentrically. Due to the delayed release of the outlet opening of the inlet connection, at the moment when the flow first enters the pipe bridge, an opening cross section of the inlet opening of the outlet connection that is enlarged in relation to the outlet opening is available. This has the advantage that a fluid flow from the housing sealing seat at the outlet socket enters the pipe bridge in an offset manner and thus direct flow against the housing sealing seat is prevented. This at least reduces the erosion of the housing sealing seat and increases the service life of the knife gate valve.

In a preferred embodiment, the guide element is adapted in such a way that the opening cross section forms at least one gap between the pipe bridge and the inlet pipe at the moment of the first flow entry from the inlet pipe into the pipe bridge. The gap preferably extends in one plane with the shut-off plate. The gap results in an opening cross section that is enlarged compared to the known punctiform opening cross section.

The guide element is preferably adapted in such a way that the gap is arcuate in sections and linear in sections. The shape of the gap can thus connect different geometries. This is the case, for example, with a straight outer edge of the guide element. A first long side of the gap is straight or linear and the opposite second long side of the gap is arcuate. The straight long side is determined by the outer edge of the guide element and the arched, curved long side by the inner wall of the pipe bridge. Surprisingly, it has been shown that such a shape of the gap is particularly favorable in terms of flow technology.

It is not necessary for the outer edge of the guiding element to lie in the plane of the outlet opening of the inlet connection. The distance between the outer edge and the level of the outlet opening is such that an unintentional passage of fluid in the initial phase when opening is avoided or at least significantly reduced and a shielding effect is created.

The guide element has at least one outer contour at the outlet opening of the inlet connection piece, which extends transversely to the opening and closing direction of the knife gate valve. The transverse extension of the outer contour has the effect that part of the outlet opening of the inlet connector is shielded from the fluid flow. The outer contour can have the straight outer edge already mentioned above, in particular a horizontally arranged straight outer edge. Alternatively, the outer contour can have a curved outer edge.

In a further preferred embodiment, the guide element has at least one outer contour at the outlet opening of the inlet connector, which corresponds to an inner contour of a passage of the pipe bridge. In other words, the guide element has at least one outer contour at the position of the outlet opening of the inlet connection piece, the shape of which corresponds to an inner contour of a passage of the pipe bridge. The outer contour of the guide element and the inner contour of the passage preferably border in a longitudinal direction of the inlet connection to each other. The pipe bridge can be moved relative to the inner contour of the passage transversely to the longitudinal direction of the inlet connection in relation to the outer contour of the guide element. The outer contour of the guiding element is preferably an outer edge, which is arranged at the position, in particular in the longitudinal direction, of the outlet opening of the inlet connector. The inner contour of the passage of the pipe bridge is preferably part of an inner circumference of the passage. The passage is preferably an opening that extends through the pipe bridge and fluidly connects the inlet and outlet connectors to one another at least in the open position. During the opening process, at the moment when the flow first enters the passage of the pipe bridge, an elongate opening cross-section is released through which the fluid stream flows distributedly into the passage. As a result, the flow speed of the fluid stream and thus the erosive effect, for example on the housing sealing seat on the outlet side, is reduced. These statements also apply to the embodiment with a straight outer edge.

The outer contour of the guide element and the inner contour of the passage of the pipe bridge preferably have the same, in particular the same, radius of curvature. The outer contour of the guide element can be formed in the shape of a circular arc. The inner contour of the passage of the pipe bridge can be circular. The outer contour of the guide element is preferably convex. It is possible for sections of the outer contour of the guide element to have the same radius of curvature as the inner contour of the passage. The passage of the pipe bridge is preferably cylindrical. The passage is preferably part of a compensator unit of the pipe bridge. The design of the outer and inner contour as a curve has the advantage that the opening cross-section of the outlet opening of the inlet connection is linear or gap-shaped at the moment when the flow first enters the passage of the pipe bridge and thus a comparatively calm inflow of the fluid flow is realized. This also applies to the embodiment with a straight outer edge.

More preferably, the outer contour extends inwards transversely to the longitudinal direction of the inlet connection piece, starting from the inner wall. In other words, the outer contour of the guide element runs from the inner wall of the inlet connector transversely to the longitudinal direction into the interior of the inlet connector and thus reduces the outlet opening. The outer contour of the guiding element is arranged in the longitudinal direction of the inlet connector at the position of the outlet opening. The outer contour of the guiding element preferably has two ends which are in contact with the inner wall. Furthermore, the outer contour of the guide element preferably has at least one apex, which lies transversely to the longitudinal direction in the interior of the inlet connector. In other words, the apex is offset or spaced inwards from the inner wall of the inlet connection piece transversely to the longitudinal direction. This embodiment represents a simple solution, on the one hand to reduce the outlet opening and on the other hand to increase the opening cross section at the moment of the first flow entry.

In a preferred embodiment, the guide element has a surface that is straight and protrudes along the direction of flow with increasing distance from the inner wall into the inlet connector. The guide element is preferably a flat element that extends over a region of the inner wall of the inlet connection. The increasing distance results in a continuous reduction of the effective flow cross-section of the inlet connector, on the one hand to increase the opening cross-section of the outlet opening of the inlet connector and on the other hand to redirect the fluid flow with the least possible turbulence, so that the outlet opening of the inlet connector is temporarily shielded in the initial phase of opening. A bouncing of the fluid flow in the sense of a baffle plate and the resulting strong turbulence of the fluid are largely avoided.

Alternatively, starting from the inner wall, the surface can curve towards the inside of the inlet connector. The guide element preferably has a hump-like shape. The guide element is preferably a flat element that extends over a region of the inner wall of the inlet connection. The surface of the guide element preferably has a convex curvature that extends into the interior of the inlet connector. The curvature of the surface preferably runs transversely and/or in the longitudinal direction of the inlet connection.

The surface of the guiding element preferably faces the interior of the inlet connection. The guide element preferably terminates flush with the surface on the inner wall of the inlet connector. The guide element can be formed from sheet metal. A cavity can be provided here between the guide element and the inner wall of the inlet connection. Alternatively, the baffle may be formed from a solid material that fills a space between the surface of the baffle in the inner wall of the inlet port. The curved surface advantageously has a flow-optimized shape, so that a pressure loss of the plate slide is kept low. In contrast to this, the knife gate valve is built according to DE 10 2016 111 169 A1 , especially in the open position of the gate valve, an increased dynamic pressure due to the impacting fluid flow. at In the described embodiment of the knife gate valve according to the invention, there is no increased pressure on the guide element when the knife gate valve is in the open state. Furthermore, the curved shape has the advantage that the fluid flow does not impinge, as is the case with the baffle plate known from the prior art, and wear on the guide element is therefore reduced. The same explanations apply to a guiding element with a straight surface which rises in the direction of flow, ie which protrudes into the interior of the inlet connection piece in a continuously increasing manner in the direction of flow.

The guide element is preferably designed to rise in the direction of flow towards the outlet opening of the inlet connector. In other words, the guide element forms a ramp that rises in the direction of flow from the inner wall to the outlet opening of the inlet connector. The guide element can run continuously, in particular evenly, rising towards the outlet opening. More preferably, the guide element extends at least partially in a longitudinal direction of the inlet connector and ends at the outlet opening of the inlet connector. In other words, the guiding element has an end which is arranged in the longitudinal direction of the inlet connection at the position of the outlet opening. The outer contour of the guide element is preferably formed at the end. The guide element can extend in sections or over the entire length of the inlet connection. This embodiment has advantages in terms of flow technology. Here the fluid flow is guided continuously, i.e. free of an impact edge or impact step, to the outlet opening. These explanations apply both to the guide element with a straight surface and for the guide element with a curved surface.

The guide element can have a triangular cross section or form a triangular cross section together with the inner wall. This embodiment is to be seen in connection with the directing element with a straight surface, which continuously projects further into the interior of the inlet connection piece in the direction of flow. In this case, the guide element can have a triangular cross section, such as in the case of a solid guide element. If the guide element is designed as a metal sheet, the metal sheet and the inner wall together form the triangular cross section.

The triangular cross section can extend along the width, in particular the entire width of the guide element. It goes without saying that the size of the triangular cross-section varies in the circumferential direction of the inlet connection. If the triangular cross section extends along the width, in particular the entire width of the guide element, the result is that the guide element effects a gradual deflection of the fluid flow to shield the outlet opening.

A drainage gap is preferably formed between the guide element and the inner wall of the inlet connection piece. As a result, liquid, for example condensate, can run off in a controlled manner.

In a preferred embodiment, the inlet connector and the outlet connector each have a sealing seat for the at least one shut-off plate. Preferably, the inlet connector and the outlet connector for a total of two shut-off plates each have a sealing seat in order to provide a tight connection in the closed position. The guide element, in particular the outer contour, is offset inwards at least in sections from the sealing seat of the outlet connection piece transversely to the longitudinal direction. This has the advantage that when the knife gate valve is opened, the opening cross section of the outlet opening of the inlet connection is released with a delay in relation to an opening cross section of the inlet opening of the outlet connection. This prevents direct flow against the sealing seat of the outlet connector and thus at least reduces or completely prevents erosion of the sealing seat.

In one embodiment, an opening cross section of the inlet opening of the outlet connector is larger than the opening cross section of the outlet opening of the inlet connector when the knife gate valve is opened and/or in the open position of the knife gate valve. The opening cross section of the outlet opening of the inlet connection and the opening cross section of the inlet opening of the outlet connection can be in a ratio of at least 1 to 2 (“1:2”). A larger ratio than 1 to 2 of the opening cross-sections is possible. The ratio relates to the areas of the opening cross-sections.

The guiding device can have a further guiding element which is arranged in a direction of displacement of the blocking device between the blocking plate and the pipe bridge. The further guide element forms a flow channel transversely to the direction of displacement, which connects the inlet port to the outlet port at least when the knife gate valve is opened. With regard to the advantages, reference is made to the advantages explained in connection with the knife gate valve described below.

• - ein Schiebergehäuse, das einen Einlassstutzen mit einer Ausgangsöffnung und einen Auslassstutzen mit einer Eingangsöffnung aufweist, die in einer Offenstellung des Plattenschiebers miteinander korrespondieren;
• - eine Sperreinrichtung mit wenigstens einer Absperrplatte, insbesondere zwei Absperrplatten, und einer Rohrbrücke, die zum Öffnen und Schließen des Plattenschiebers zwischen dem Ein- und Auslassstutzen beweglich angeordnet sind; und
• - wenigstens eine Leiteinrichtung zur Strömungsleitung.

Die Leiteinrichtung weist wenigstens ein Leitelement auf, das in einer Verschieberichtung der Sperreinrichtung zwischen der Absperrplatte und der Rohrbrücke angeordnet ist, wobei das Leitelement einen Strömungskanal quer zur Verschieberichtung bildet, der zumindest beim Öffnen des Plattenschiebers den Einlassstutzen mit dem Auslassstutzen verbindet.According to the independent claim 17, the invention relates to a knife gate valve, in particular a double knife gate valve, for chemical and/or petrochemical industrial plants, comprising:

• - A slide housing, which has an inlet connection with an outlet opening and an outlet connection with an inlet opening, which correspond to one another in an open position of the plate slide;
• - A blocking device with at least one blocking plate, in particular two blocking plates, and a pipe bridge, which are movably arranged for opening and closing the plate slide between the inlet and outlet; and
• - At least one guiding device for the flow line.

The guiding device has at least one guiding element, which is arranged between the shut-off plate and the pipe bridge in a displacement direction of the blocking device, with the guiding element forming a flow channel transverse to the displacement direction, which at least when the plate slide valve is opened connects the inlet connection with the outlet connection.

This has the advantage that when the plate slide valve is opened through the flow channel before the release, a passage from the outlet opening of the inlet connector into the passage of the pipe bridge takes place. This means that the fluid pressure on the inlet side is already reduced in advance or the dirt deposited on the inlet side is at least partially removed by the flow channel. As a result, the fluid flow through the passage of the pipe bridge contains fewer particles, so that the housing sealing seat on the outlet side is protected. This increases the erosion resistance and service life of the knife gate valve.

The plate slide preferably has at least two guide elements, each of which forms a flow channel through the blocking device transversely to the direction of displacement. In a preferred embodiment, the guide element is integrated into the blocking device, with the flow channel running completely through the blocking device transversely to the displacement direction. The guide element is preferably formed by at least one piece of pipe.

According to the independent claim 20, the invention relates to a method for operating a knife gate valve, in particular one of the aforementioned type, for chemical and/or petrochemical industrial plants, in which the knife gate valve comprises a valve housing with an inlet connection and an outlet connection and a blocking device which is Slider housing is moved between an open position and a closed position for opening and closing the knife gate valve. The blocking device has at least one blocking plate and a pipe bridge with a passage, which is arranged in the open position such that the inlet connection is connected to an outlet opening and the outlet connection to an inlet opening through the passage of the pipe bridge. In the closed position, the blocking device is arranged in such a way that the inlet connector and the outlet connector are blocked from one another by the blocking plate. The knife gate valve has at least one guiding device with at least one guiding element for guiding the flow, which is arranged on an inner wall of the inlet connection and reduces the outlet opening of the inlet connection. When the blocking device is moved from the closed position to the open position, at the moment of an initial, in particular first, flow entry into the passage of the pipe bridge, an enlarged, in particular gap-shaped, opening cross section of the outlet opening of the inlet connection is released, which is defined by the guide element and the passage of the pipe bridge .
In a preferred embodiment of the method according to the invention, the opening cross section of the outlet opening of the inlet connection is released linearly, in particular uniformly, over the entire displacement path of the blocking device when the knife gate valve is opened.

According to the independent claim 22, the invention relates to a method for operating a knife gate valve, in particular according to one of the knife gate valves of the aforementioned type, for chemical and/or petrochemical industrial plants, in which the knife gate valve comprises a valve body with an inlet connection and an outlet connection and a blocking device which in the slide housing is shifted between an open position and a closed position for opening and closing the knife gate valve. The blocking device has at least one blocking plate and a pipe bridge with a passage, which is arranged in the open position such that the inlet connection is connected to an outlet opening and the outlet connection to an inlet opening through the passage of the pipe bridge. In the closed position, the blocking device is arranged in such a way that the inlet connector and the outlet connector are blocked from one another by the blocking plate. The plate slide has at least one guiding device with at least one guiding element for guiding the flow, which is arranged in a direction of displacement of the blocking device between the blocking plate and the pipe bridge. The guide element forms a flow channel transverse to the direction of displacement, which connects the inlet connection piece to the outlet connection piece when the blocking device is moved from the closed position into the open position, before the passage the pipe bridge releases an opening cross section of the outlet opening of the inlet connection.

Regarding the advantages of the methods for operating the knife gate valve, reference is made to the advantages explained in connection with the knife gate valves. In addition, the methods can alternatively or additionally have individual features or a combination of several features mentioned above in relation to the knife gate valve.

When using one of the plate slide valves of the aforementioned type according to the invention, these are used in a cracking process and/or a coking process.

The invention will be explained in more detail below with reference to the accompanying drawings. The illustrated embodiments represent examples of how the knife gate valve according to the invention can be designed.

• 1 einen Längsschnitt durch einen Plattenschieber nach einem bevorzugten erfindungsgemäßen Ausführungsbeispiel, wobei sich eine Sperreinrichtung des Plattenschiebers in einer Schließstellung befindet;
• 2 eine perspektivische Detailansicht eines Einlassstutzens mit einer Leiteinrichtung des Plattenschiebers gemäß 1;
• 3 einen Längsschnitt durch den Plattenschieber gemäß 1, wobei sich die Sperreinrichtung des Plattenschiebers in einer Stellung befindet, an der lediglich die Eingangsöffnung des Auslassstutzens des Plattenschiebers mit dem Durchgang der Rohrbrücke verbunden ist;
• 4 eine perspektivische Detailansicht des Einlassstutzens und der Leiteinrichtung des Plattenschiebers gemäß 1, wobei ein Öffnungsquerschnitt der Ausgangsöffnung des Einlassstutzens in der Stellung gemäß 3 gezeigt ist;
• 5 eine schematische Darstellung zur Illustration des Öffnungsquerschnitts der Ausgangsöffnung des Einlassstutzens in der Stellung gemäß 3, die den Moment des ersten Strömungseintritts in die Rohrbrücke zeigt;
• 6 einen Längsschnitt durch den Plattenschieber gemäß 1, wobei die Sperreinrichtung des Plattenschiebers weiter in Richtung der Offenstellung bewegt ist;
• 7 eine perspektivische Detailansicht des Einlassstutzens und der Leiteinrichtung des Plattenschiebers gemäß 1, wobei der Öffnungsquerschnitt der Ausgangsöffnung des Einlassstutzens weiter vergrößert ist;
• 8 ein Diagramm zur Darstellung der Öffnungsphase der Ausgangsöffnung des Einlassstutzens des Plattenschiebers gemäß 1;
• 9 eine Draufsicht auf einen Plattenschieber nach einem weiteren erfindungsgemäßen Ausführungsbeispiel; und
• 10 eine perspektivische, teiltransparente Ansicht einer Sperreinrichtung des Plattenschiebers gemäß 9.
• 11 eine Draufsicht auf einen Plattenschieber im Bereich des Einlassstutzens nach einem weiteren erfindungsgemäßen Ausführungsbeispiel, bei dem das Leitelement eine gerade Außenkante aufweist;
• 12 eine perspektivische Ansicht des Plattenschiebers gemäß 11 im Bereich des Einlassstutzens;
• 13 einen Schnitt des Einlassstutzens des Plattenschiebers gemäß 11;
• 14 eine perspektivische Ansicht des geschnittenen Einlassstutzens gemäß 13 und des zugehörigen geschnittenen Auslassstutzens und
• 15 eine schematische Darstellung zur Illustration des Öffnungsquerschnitts der Ausgangsöffnung des Einlassstutzens gemäß 11 in einer Stellung, die den Moment des ersten Strömungseintritts in die Rohrbrücke zeigt.

In these show

• 1 a longitudinal section through a plate slide according to a preferred embodiment of the invention, wherein a locking device of the plate slide is in a closed position;
• 2 a detailed perspective view of an inlet connection with a guiding device of the knife gate valve according to FIG 1 ;
• 3 according to a longitudinal section through the knife gate valve 1 wherein the knife gate valve locking device is in a position where only the inlet opening of the knife gate valve outlet port is connected to the passage of the pipe bridge;
• 4 a detailed perspective view of the inlet connection and the guiding device of the gate valve according to FIG 1 , wherein an opening cross-section of the outlet opening of the inlet connector in the position according to 3 is shown;
• 5 a schematic representation to illustrate the opening cross section of the outlet opening of the inlet connection in the position according to FIG 3 , which shows the moment of the first flow entry into the pipe bridge;
• 6 according to a longitudinal section through the knife gate valve 1 , wherein the locking device of the plate slide is moved further towards the open position;
• 7 a detailed perspective view of the inlet connection and the guiding device of the gate valve according to FIG 1 , wherein the opening cross section of the outlet opening of the inlet connection is further increased;
• 8th a diagram showing the opening phase of the outlet orifice of the knife gate valve inlet nozzle according to FIG 1 ;
• 9 a plan view of a knife gate valve according to a further embodiment of the invention; and
• 10 a perspective, partially transparent view of a locking device of the plate slide according to 9 .
• 11 a plan view of a knife gate valve in the area of the inlet connection according to a further exemplary embodiment according to the invention, in which the guide element has a straight outer edge;
• 12 a perspective view of the gate valve according to FIG 11 in the area of the inlet port;
• 13 a section of the inlet nozzle of the knife gate valve according to 11 ;
• 14 a perspective view of the sectioned inlet nozzle according to FIG 13 and the associated cut outlet nozzle and
• 15 a schematic representation to illustrate the opening cross section of the outlet opening of the inlet connector according to FIG 11 in a position showing the moment of the first flow entry into the pipe bridge.

In the following description, the same reference numbers are used for the same parts and parts with the same effect.

the 1 until 7 Fig. 12 shows a knife gate valve 10 according to a preferred embodiment of the invention, the knife gate valve 10 being a double knife gate valve.

The plate slide valve 10 has a slide housing 11 which fluid-tightly surrounds built-in components located in the slide housing 11 . The slide housing 11 has an inlet connection 12 and an outlet connection 14 . The inlet and outlet sockets 12, 14 are each designed as pipe sockets. In the installed state, the inlet and outlet connectors 12, 14 are flanged to corresponding lines (not shown), for example a transfer line or a decoking line.

The inlet socket 12 has an outlet opening 13 and the outlet socket 14 has an inlet opening 15, which correspond to one another when the knife gate valve 10 is in an open position. The inlet and outlet ports 12, 14 lie on a common longitudinal axis.

Furthermore, the gate valve 10 has a blocking device 16 which comprises two blocking plates 17 and a pipe bridge 18 . The shut-off plates 17 are placed in a plate cage 34 . The shut-off plates 17 are arranged concentrically and parallel to one another and shut off the inlet and outlet sockets 12, 14 in a closed position. The shut-off plates 17 are placed loosely in the plate cage 34 so that they can be moved in the axial direction, i.e. perpendicular to the surface of the shut-off plates 17. In other words, the blocking device 16 can be displaced transversely to the longitudinal axis of the sockets 12, 14. This is used to press the shut-off plates 17 in the closed position against the housing sealing seats 29 provided on the valve housing 11 . For this purpose, a spreading element 35 is arranged between the two shut-off plates 17 and is connected to a slide rod 36 . The slide rod 36 is mounted in the slide housing 11 in a fluid-tight manner and can be moved in the longitudinal direction by a drive (not shown). The spreading element 35 has an inner wedge 37 which is arranged in an outer wedge 38 on the inside of the shut-off plates 17 . A centering ball 39 is arranged between the jaws of the inner wedge 37 in order to center the expansion element 35 .

The pipe bridge 18 is firmly connected to the plate basket 34. In other words, the pipe bridge 18 is arranged on the plate cage 34 on a side opposite the slide rod 36 . The pipe bridge 18 has a passage 26 which is aligned with the inlet and outlet sockets 12, 14 in the open position. The pipe bridge 18 is connected to the plate cage 34 in such a way that it can be moved into the open or closed position together with the plate cage 34 by actuating the slide rod 36 . For this purpose, the plate basket 34 and the pipe bridge 18 are moved between two guide plates arranged in parallel.

The pipe bridge 18 has a compensator unit 41 which includes the passage 26 . The compensator unit 41 has two sealing rings 42 which are arranged concentrically and spaced apart from one another in the axial direction. A compensator shaft 43 is arranged between the two sealing rings 42 . In the present exemplary embodiment, this has a multi-wave design. Single-shaft compensator shafts are also possible, especially with smaller nominal diameters.

When the slide rod 36 is actuated, the inner wedge 37 is moved into the outer wedge 38, as a result of which the two shut-off plates 17 are spread apart. The two shut-off plates 17 are pressed against the housing sealing seats 29 by the spreading movement, as a result of which a good sealing effect is achieved in the closed position of the plate slide 10 .

the 1 , 3 and 6 show an opening process of the gate valve 10, in which the blocking device 16 is moved from the closed position to the open position. For this purpose, the blocking device 16 is movably arranged between the inlet and outlet connections 12 , 14 .

The knife gate valve 10 also includes a guide device 19 for guiding an inflowing fluid flow. The guiding device 19 has a guiding element 21 which is arranged on an inner wall 22 of the inlet connector 12 . The guide element 21 is arranged on the pipe bridge side on the inner wall 22 of the inlet connection piece 12 as viewed in the displacement direction of the blocking device 16 .

The inner wall 22 of the inlet connector 12 is cylindrical. The inner wall 22 of the inlet connector 12 has an inner circumference on which the guide element 21 rests.

As in the 1 , 3 and 6 is clearly visible, the guide element 21 extends in a longitudinal direction of the inlet connection 12 and ends at the position of the outlet opening 13 of the inlet connection 12. The guide element 21 extends almost over the entire length of the inlet connection 12. The guide element 21 rises to the outlet opening 13 of the inlet connection 12 on. In other words, the guide element 21 is designed to run obliquely into the interior of the inlet connector 12 toward the outlet opening 13 . The guide element 21 is designed in the form of a ramp towards the outlet opening 13 of the inlet connector 12 . The guiding element 21 has a surface 28 which faces the interior of the inlet connection piece 12 . During operation, this is in contact with the fluid or a fluid flow. The surface 28 ends flush with the inner wall 22 of the inlet connector 12 . This is in the 2 and 4 clearly visible. The surface 28 covers a portion of the inner wall 22.

Furthermore, from the 2 , 4 , 5 and 7 shows that the surface 28 of the guide element 21 is curved. The guide element 21 is hump-shaped due to the curved surface 28 . In other words, the guide element 21 is a flat element that extends over an area of the inner wall 22 of the inlet connector 12 . The surface 28 of the guide element 21 specifically has a convex curvature transverse to the longitudinal direction of the inlet connection piece 12 , which extends into the interior of the inlet connection piece 12 . The guide element 21 is partially shell-shaped.

The guide element 21 is made of sheet metal. In other words, the guide element 21 forms a guide plate. It is possible for the guide element 21 to be in the form of a guide plate. In contrast to the baffle, a baffle has a greater wall thickness. Alternatively, the guide element 21 can be formed from a solid material that completely fills a space between the surface 28 and the inner wall 22 of the inlet connector 12 .

The guide element 21 ends in the longitudinal direction at the position of the outlet opening 13 of the inlet connection 12. At this position, the guide element 21 has an outer contour 24 which corresponds to an inner contour 25 of the passage 26 of the pipe bridge 18. The inner contour 25 and the outer contour 24 are arranged adjacent in the longitudinal direction of the inlet connection piece 12 . The inlet connector 12 has one of the two sealing seats 29 at the position of the outlet opening 13 . Along the common longitudinal axis opposite the outlet opening 13 , the outlet connector 14 has another of the two sealing seats 29 at the position of the inlet opening 15 . The guide element 21 is offset by the shape of the outer contour 24 from the sealing seat 29 of the outlet connector 14 and in particular from the sealing seat 29 of the inlet connector 12, transversely to the longitudinal direction inwards.

The outer contour 24 of the guide element 21 forms an outer edge. The outer contour 24 of the inlet connector 12 forms the inner contour 25 of the passage 26 of the pipe bridge 18 . Specifically, the inner contour 25 is a circular, in particular circular, inner circumference of the passage 26. The outer contour 24 of the guide element 21 is therefore formed in the shape of a circular arc. Specifically, the outer contour 24 of the guide element 21 forms a circular arc section. The outer contour 24 of the inlet connector 12 and the inner contour 24 of the passage 26 of the pipe bridge 18 have the same radius of curvature.

The outer contour 24 of the guide element 21 terminates at the inner wall with two ends, with an intermediate apex being arranged transversely to the longitudinal direction in the outlet opening 13 . The outer contour 24 of the guide element 21 is therefore convexly curved.

The outlet opening 13 of the inlet connector 12 is reduced by the guide element 21 , since the guide element 21 protrudes with the outer contour 21 into the outlet opening transversely to the longitudinal direction of the connector 12 . Due to the specially shaped outer contour 24 of the guide element 21, which corresponds to the adjacent inner contour 25 of the pipe bridge 18, when the knife gate valve opens, an opening cross section 23 of the outlet opening 13 of the inlet connection 12 is at the moment of the first flow entry from the inlet connection 12 into the passage 26 of the pipe bridge 18 enlarged.

As in 4 and 5 clearly visible, the guide element 21 is designed such that at the moment of the first flow entry from the inlet connection 12 into the pipe bridge 28, the opening cross section 23 of the outlet opening 13 of the inlet connection 12 forms a cross-sectional shape that deviates from a punctiform cross section. This corresponds, for example, to an enlarged opening cross section. The opening cross section 23 is linear at the moment of the first flow entry from the inlet connector 12 into the pipe bridge 18 . At the moment of the first flow entry from the inlet connection piece into the passage 26 of the pipe bridge 18, the opening cross section can have a passage area that encompasses a larger extent than a punctiform opening. The opening cross section 23 forms a gap at the moment of the first flow entry from the inlet connector 12 into the passage 26 of the pipe bridge 18 . The gap is arcuate. In other words, the gap is annular. Alternatively or additionally, the gap can be linear, at least in sections.

The opening cross section 23 of the outlet opening 13 of the inlet connector 12 is currently and during the entire opening process by an inner circumference of the inner wall 22 of the inlet connector 12, the outer contour 24 of the guide element 21 and the inner contour 25 of the passage 26 of the pipe bridge 18 delimited. In other words, the inner circumference of the inner wall 22 of the inlet socket 12, the outer contour 24 of the guide element 12 and the inner contour 25 of the passage 26 of the pipe bridge 18 define the size of the opening cross section 23 of the outlet opening 13 of the inlet socket 12 into the pipe bridge 18 when the knife gate valve is opened and closed .

The opening cross section 23 of the outlet opening 13 of the inlet connection 12 is always smaller than an opening cross section 31 of the inlet opening 15 of the outlet connection 14 when the knife gate valve 10 is opening and/or in the open position of the knife gate valve 14. This is shown in FIG 3 to see.

Subsequently, the opening process of the gate valve 10 according to 1 until 7 described.

When the blocking device 16 is moved from the closed position to the open position of the knife gate valve 10, at the moment of an initial or first entry of a fluid flow into the passage 26 of the pipe bridge 18, a linear, in particular gap-shaped, opening cross section 23 of the outlet opening 13 of the Inlet socket 12 is released, which is defined by the outer contour 24 of the guide element 21 and the inner contour 25 of the passage 26 of the pipe bridge 18 adjoining it. In 1 the knife gate valve 10 is shown in the closed position. In 4 such as 5 the line-shaped or gap-shaped opening cross section 23 can be seen at the moment when the fluid flow first enters the passage 26 of the pipe bridge 18 .

Through the opening cross-section 23, which is enlarged compared to a punctiform opening, the fluid mixed with particles flows distributed over the opening cross-section 23 into the passage 26 of the pipe bridge 18. The flow speed of the fluid stream is thereby reduced in comparison to the punctiform opening. Furthermore, the outlet opening 13 is opened with a delay in relation to the inlet opening 15 of the outlet connection piece 14 by the guide element 21 in the inlet connection piece 12, as shown in FIG 3 or according to the diagram 8th is clearly recognizable. In 8th the curve K1 represents the area of the opening cross section 32 of the inlet opening 15 of the outlet connection 14 as a function of the stroke position of the blocking device 16 or the slide rod 36. Furthermore, the curve K2 represents the area of the opening cross section 23 of the outlet opening 13 of the inlet connection 12 as a function of the Stroke position of the blocking device 16 or the slide rod 36. From this it can be clearly seen that at the moment of the first flow entry there is already a passage opening from the passage 26 into the outlet socket 14. The delayed inflowing fluid flow is thereby discharged through the opening cross section 31 of the inlet opening 15 of the outlet connection 14 quickly and without subjecting the sealing seat 29 on the outlet connection 14 to an excessively abrasive load.

During the further opening of the gate valve 10, the through 6 and 7 is shown as an example, the opening cross section 23 is released continuously, in particular evenly.

The path of travel between the open position and the closed position, which the locking device 16 covers, e.g. during the opening process, corresponds to a total stroke of the locking device 16, in particular of the slide rod 36. In the closed position, the locking device 16 is arranged at a minimum stroke position and the locking device is in the open position 16 arranged at a maximum lift position. In other words, the blocking device 16 has a stroke of 0 percent of the total stroke in the closed position and a stroke of 100 percent of the total stroke in the open position.

The stroke range in which the opening cross section 23 of the outlet opening 13 of the inlet connector 12 influences an applied process pressure can include 0 percent up to 35 percent of the total stroke. This stroke range corresponds to the opening phase of the knife gate valve 10. The opening phase, in which the moment of the first flow entering through the outlet opening 13 of the inlet connection 12 into the pipe bridge 18, can take place with a stroke of the blocking device 16 of 22 percent to 35 percent, in particular of 22 percent up to 30 percent of the total stroke. The moment of the first flow entry through the outlet opening 13 of the inlet connection 12 into the pipe bridge 18 preferably occurs at a stroke of the blocking device 16 of 23 percent to 28 percent, in particular 24 percent to 26 percent of the total stroke. Particularly preferably, the moment of the first flow entry through the outlet opening 13 of the inlet connection 12 into the pipe bridge 18 occurs at a lift of 25 percent of the total lift.

9 and 10 show another inventive embodiment of a knife gate valve 10, which differs from the knife gate valve 10 according to 1 until 7 in the guide device 19 to the flow line, specifically in the guide element, and the blocking device 16 differs. Only the distinguishing features of the knife gate valve 10 are described below 9 and 10 described. All features of the slide valve 10 not described in accordance with 9 and 10 are in accordance with those of the disk valve 10 1 until 7 identical.

The gate valve 10 has a plurality of guide elements 21 ′, which are arranged between the two shut-off plates 17 and the pipe bridge 18 in a displacement direction of the blocking device 16 . The guide elements 21 ′ each form a flow channel 32 transverse to the direction of displacement, which connects the inlet connection piece 12 to the outlet connection piece 14 at least when the knife gate valve 10 is opened. The respective flow channel 32 penetrates the blocking device 16 transversely to the displacement direction of the blocking device 16. In other words, the respective flow channel 32 extends in the longitudinal direction of the inlet and outlet connectors 12, 14. According to FIG 9 and 10 the knife gate valve 10 has a total of two guide elements 21 ′, each of which forms a flow channel 32 .

The guide elements 21 are tubular. In concrete terms, the guide elements 21 ′ are formed by pieces of pipe which are integrated into the blocking device 16 . Alternatively, the guide elements 21' can be formed by profiled tube pieces. The guiding elements 21 ′ run parallel through the blocking device 16 . The guide elements 21 'are arranged lying between the shut-off plates 17 and the pipe bridge 18 on a common plane.

As in 10 1, the guide elements 21' are arranged in the disc basket 34. FIG. This means that when the blocking device 16 moves between the open and closed position and vice versa, the guide elements 21 ′ move with the blocking device 16 . This has the advantage that during an opening operation of the knife gate valve 10 before the release of an opening cross section 23 of the outlet opening 13 of the inlet connection 12 into the passage 26 of the pipe bridge 18, a fluid connection of the inlet and outlet connections 12, 14 takes place. That is to say, the fluid pressure on the inlet side is already reduced in advance or the contamination deposited on the inlet side is fed through the flow channels to the outlet connector 14 . The guide elements 21' form bypass channels to the passage 26 of the pipe bridge 18, which diverts the fluid flow during an opening process before the passage into the passage 26 of the pipe bridge 18 is released from the inlet connector 12 to the outlet connector 14 (see Fig 9 ). As a result, the fluid flow through the passage 26 of the pipe bridge 18 contains fewer particles, so that the housing sealing seat 29 on the outlet side is protected.

The embodiment according to 11 until 17 differs from the embodiment according to 1 until 7 only by the shape of the guide element 21 and by some detailed features of the guide element 21. All statements in connection with the embodiment according to 1 until 7 are therefore in accordance with the embodiment 11 until 17 transferable and are in accordance with the embodiment 11 until 17 disclosed and claimed.

In addition, the combination of the embodiments according to the 9 , 10 and 11 until 17 revealed and claimed.

As in the 11 , 12 clearly recognizable, the knife gate valve 10 has a valve housing 11 with an inlet connection 12 . In the inlet connection 12 delimits an outlet opening 13 which is aligned with the inlet opening 15 of the corresponding outlet connection 14 .

A blocking device 16 , which includes blocking plates 17 and a pipe bridge 18 , is provided for actuating the plate slide 10 . For the details of the blocking device 16, reference is made to the explanations in connection with the exemplary embodiment according to FIG 1 until 7 referred.

On the side of the pipe bridge, the inlet socket 12 has a guide device 19 with a guide element 21 .

The difference to the guide element 21 according to 1 until 7 is that the outer contour 24 of the guide element 21 according to 11 until 15 forms a straight outer edge. It has been shown that the flow conditions in the initial phase of opening the knife gate valve as 10 are improved by the straight outer edge.

The geometry of the guide element 21 is described in more detail as follows. The straight outer edge extends as in 12 clearly visible, practically on the same level as the peripheral boundary of the outlet opening 13. The straight outer edge runs essentially perpendicularly to the opening and closing direction of the blocking device 16. This is also shown in the schematic representation according to FIG 15 clearly visible.

The surface of the guide element, the surface 28 of the guide element 21 is also straight, i.e. not curved.

Similar to the embodiment according to FIG 1 until 7 the guide element 21 protrudes into the interior of the inlet connector 12. The surface 28 is arranged inclined relative to the inner wall of the inlet connector 12. The distance between the surface 28 and the inner wall of the inlet connector 12 increases continuously in the direction of flow, ie in the direction of the outlet opening 13 . This shape of the guide element 21 is well in accordance with the cross section 13 to recognize. The distance of the surface 28 from the inner wall of the inlet nozzle 12 is maximum at the straight outer edge. This shape of the guide element 21 is well in accordance with the cross section 13 to recognize.

As in 12 It can also be seen that the outer contour 24 of the guide element 21, specifically the straight outer edge, is practically at the same height as the exit opening 13. A slight gap between the shut-off plate 17 and the outer edge is possible, provided that the exit opening 13 is shielded by the guide element 21 in this way that a fluid flow in the initial phase of opening the gate valve 10 is at least largely avoided.

13 , 14 show the triangular cross section of the guide element 21. In the example according to FIG 13 , 14 the guide element 21 is made of solid material, ie is solid. Alternatively, the guiding element 21 can comprise a metal sheet that is connected to the inner wall of the inlet connection piece 12 . In this case, the triangular cross-section is formed by the inner wall of the inlet port 12 and the baffle. In the surface 28 is straight. The triangular cross section of the guide element 21 thus extends over its entirety Broad. The surface 28 has the same slope at all points.

In the 13 , 14 a drainage gap 24 is shown, which extends between the rear side of the guide element 21, ie on the side facing away from the surface 28, and the inner wall of the inlet connection piece 12. Liquid, for example condensate, can drain through the drain gap 24 .

A fastening means 45, for example in the form of a cam, is provided for fastening the guide element 21 in the inlet connection piece 12, which means firmly or detachably connects the guide element to the inlet connection piece 12. Other fastening means are possible. For example, the guide element 21 can be welded into the inlet port. The cam is hook-shaped so that the guide element 21 can be placed on it with a corresponding receiving opening. Other cam shapes are possible. For example, the cam can be straight in the case of smaller nominal widths.

The surface 28 is designed to be wear-resistant. For this purpose, for example, hardfacing can be provided on the surface 28 by build-up welding.

The detailed features mentioned above, such as the drainage gap 44, the fastening means 45 and the hardfacing, are also described in connection with the guide element according to FIG 1 until 7 revealed and claimed.

15 shows the shape of the opening cross section 23 in the initial phase of opening, when the fluid connection between the inlet connector 12 and the outlet connector 14 is established and a partial area of the through-opening 26 of the pipe bridge 18 is released. As in 15 clearly visible, the opening cross section 23 has a combined linear and arcuate shape. The opening cross section 23 is designed as a gap in the shape of a segment of a circle. The straight side of the opening cross section 23 (chord) is delimited by the straight outer edge of the outer contour 24 . The curved side (arc) of the opening cross section 23 is determined by the radius of curvature 27 of the pipe bridge 18 .

As in the embodiment according to 1 until 7 the release of the outlet opening 13 by the guide element 21 is delayed to such an extent that the inlet opening 15 of the outlet connection piece 14 is opened wider than the outlet opening 13 of the inlet connection piece 12 before the flow passage begins. In addition, the straight outer edge means that the opening cross section is enlarged compared to the prior art, so that the undesired nozzle effect in the initial opening phase is reduced.

In this exemplary embodiment, when the inner wall of the disc basket 18 is moved past the straight outer edge, a small opening is formed for a short time. However, the opening cross-section widens so quickly as you continue to move past that a sufficiently large opening cross-section is provided and the undesired nozzle effect is practically suppressed. In addition, it is achieved that the inlet opening 15 of the outlet socket 14 is already relatively wide open before the outlet opening 13 of the inlet socket 12 is opened, so that the fluid penetrating into the pipe bridge 18 is drained off immediately and cannot collect in the pipe bridge 18.

The particle flow in the initial phase of opening a knife gate valve constructed according to the prior art without the invention is such that particles collect in the pipe bridge during opening and relatively few particles enter the pipe bridge 18 into the outlet nozzle 14 at high speed. In comparison, fewer particles get into the pipe bridge 18 when a guide element 21 according to 11 until 15 is provided, which shields the outlet opening 13 of the inlet connector 12 in the initial phase. The particle stream can pass almost unhindered through the inlet opening 15 , which is more open than the outlet opening 13 .

The same phenomenon can be observed in the fluid flow, which accumulates in the pipe bridge in the case of a knife gate valve without an invention. Due to the delay in the release of the inlet opening 13 achieved in the exemplary embodiment according to the invention and the resulting flow cross sections of different sizes, the fluid flow can pass through the opening blocking device 16 almost unhindered even in the initial phase of opening.

Finally, it is pointed out that the features of the two exemplary embodiments described are not limited to the individual exemplary embodiments, but can be freely combined with one another.

Reference List

10

knife gate valve

11

valve body

12

inlet port

13

exit port

14

outlet nozzle

15

entrance opening

16

locking device

17

shut-off plate

18

pipe bridge

19

control device

21

guiding element

21'

another guiding element

22

inner wall

23

Opening cross-section of the outlet opening of the inlet nozzle

24

outer contour

25

inner contour

26

passage

27

radius of curvature

28

surface

29

tight fit

31

Opening cross-section of the inlet opening of the outlet socket

32

flow channel

33

piece of pipe

34

plate basket

35

spreading organ

36

slide rod

37

inner wedge

38

outer wedge

39

centering ball

41

compensator unit

42

sealing rings

43

compensator shaft

44

drainage gap

45

fastener (cam)

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102016111169 A1 [0001, 0005, 0006, 0011, 0042]
• EP0450646A2 [0003]

Claims (23)

Knife gate valve (10) for chemical and/or petrochemical industrial plants, comprising: - a valve body (11) which has an inlet connection (12) with an outlet opening (13) and an outlet connection (14) with an inlet opening (15) which is in a Open position of the plate slide (10) correspond to each other; - A blocking device (16) with at least one blocking plate (17) and a pipe bridge (18) which is movably arranged for opening and closing the plate slide (10) between the inlet and outlet sockets (12, 14); and - at least one guiding device (19) for guiding the flow, characterized in that the guiding device (19) has at least one guiding element (21) which is arranged on an inner wall (22) of the inlet connection (12) and the outlet opening (13) of the inlet connection (12) is reduced in such a way that when the knife gate valve (10) is opened, an opening cross section (23) of the outlet opening (13) is enlarged at the moment of an initial, in particular first, flow entry into the pipe bridge (18). Knife gate valve (10) after claim 1 , characterized in that the guide element (21) is designed in such a way that when the knife gate valve (10) opens, the outlet opening (13) of the inlet connection (12) can be released with a delay in relation to the inlet opening (15) of the outlet connection (14). . Knife gate valve (10) according to one of the preceding claims, characterized in that the guide element (21) is adapted in such a way that the opening cross section at the moment of the first flow entry from the inlet connection (12) into the pipe bridge (18) has at least one gap, in particular a gap in a plane with the shut-off plate (17) extending gap between the pipe bridge (18) and the inlet connector (12). Knife gate valve (10) after claim 3 , characterized in that the guide element (21) is adapted such that the gap is partially arcuate and partially linear. Knife gate valve (10) according to one of the preceding claims, characterized in that the guide element (21) has at least one outer contour (24) on the outlet opening (13) of the inlet connection (12), which extends transversely to the opening and closing direction of the knife gate valve (10 ) extends. Knife gate valve (10) according to one of the preceding claims, characterized in that the outer contour (24) has a straight, in particular horizontally arranged, or a curved outer edge. Knife gate valve (10) according to one of the preceding claims, characterized in that the guide element (21) has a surface (28) which is straight and protrudes along the flow direction at an increasing distance from the inner wall (22) into the inlet connection (12). or which, starting from the inner wall (22), curves into the interior of the inlet connection (12), in particular in a hump-like manner. Knife gate valve (10) according to one of the preceding claims, characterized in that the guide element (21) has a triangular cross section or forms a triangular cross section together with the inner wall (22). Knife gate valve (10) after claim 8 , characterized in that the triangular cross-section extends along the width, in particular the entire width of the guide element (21). Knife gate valve (10) according to one of the preceding claims, characterized in that a drainage gap (44) is formed between the guide element (21) and the inner wall (22). Knife gate valve (10) according to one of Claims 5 until 10 , characterized in that the outer contour (24) extends transversely to the longitudinal direction of the inlet connector (12) starting from the inner wall (22) inwards. Knife gate valve (10) according to one of the preceding claims, characterized in that the guide element (21) is designed to rise in the direction of flow towards the outlet opening (13) of the inlet connection (12). Knife gate valve (10) according to one of the preceding claims, characterized in that the guide element (21) extends at least partially in a longitudinal direction of the inlet connection (12) and ends at the outlet opening (13) of the inlet connection (12). Knife gate valve (10) according to one of the preceding claims, in particular according to one of claims 3 until 10 , characterized in that the inlet connector (12) and the outlet connector (14) each have a sealing seat (29) for the at least one shut-off plate (17), the guide element (21), in particular the outer contour (24), being at least partially separated from the The sealing seat (29) of the outlet socket is offset inwards transversely to the longitudinal direction. Knife gate valve (10) according to one of the preceding claims, characterized in that an opening cross section (31) of the inlet opening (15) of the outlet connection (14) when opening the knife gate valve (10) and/or in the open position of the knife gate valve (10) is larger than the Opening cross section (23) of the outlet opening (13) of the inlet connection (12). Slab gate valve (10) according to one of the preceding claims, characterized in that the guide device (19) has a further guide element (21') which is arranged between the shut-off plate (17) and the pipe bridge (18) in a displacement direction of the blocking device (16). is, wherein the further guide element (21 ') forms a flow channel (32) transverse to the direction of displacement, which connects the inlet connector (12) with the outlet connector (14) at least when opening the knife gate valve (10). Knife gate valve (10) for chemical and/or petrochemical industrial plants, comprising: - a valve body (11) which has an inlet connection (12) with an outlet opening (13) and an outlet connection (14) with an inlet opening (15) which is in a Open position of the plate slide (10) correspond to each other; - A blocking device (16) with at least one blocking plate (17) and a pipe bridge (18) which are movably arranged for opening and closing the plate slide (10) between the inlet and outlet sockets (12, 14); and - at least one guiding device (19) for the flow line, characterized in that the guiding device (19) has at least one guiding element (21') which, in a direction of displacement of the blocking device (16), between the blocking plate (17) and the pipe bridge (18) is arranged, wherein the guide element (21) forms a flow channel (32) transverse to the direction of displacement, which connects the inlet connector (12) to the outlet connector (14) at least when the knife gate valve (10) is opened. Knife gate valve (10) after Claim 17 , characterized in that the guide element (21 ') is integrated into the blocking device (16), wherein the flow channel (32) transverse to the direction of displacement of the blocking device (16) runs completely. Knife gate valve (10) after Claim 17 or 18 , characterized in that the guide element (21 ') is formed by at least one piece of pipe (33). Method for operating a knife gate valve (10), in particular according to one of Claims 1 until 16 , for chemical and/or petrochemical industrial plants, in which the knife gate valve (10) comprises a valve housing (11) with an inlet connection (12) and an outlet connection (14) and a locking device (16) which is located in the valve housing (11) between a open position and a closed position for opening and closing the gate valve (10), the blocking device (16) having at least one blocking plate (17) and a pipe bridge (18) with a passage (26), which is arranged in the open position in such a way that the inlet socket (12) with an outlet opening (13) and the outlet socket (14) with an inlet opening (15) are connected to one another through the passage (26) of the pipe bridge (18), and the blocking device (16) is arranged in such a way in the closed position is that the inlet connector (12) and the outlet connector (14) are blocked from one another by the shut-off plate (17), the knife-gate valve (10) having at least one guide device (19), e.g ur flow line, characterized in that the guide device (19) has at least one guide element (21) which is arranged on an inner wall (22) of the inlet connection (12) and reduces the outlet opening (13) of the inlet connection (12), wherein at a displacement of the blocking device (16) from the closed position to the open position at the moment of an initial, in particular first, flow entry into the passage (26) of the pipe bridge (18), an enlarged, in particular gap-shaped, opening cross section (23) of the outlet opening (13) of the inlet connection (12) is released, which is defined by the guide element (21) and the passage (26) of the pipe bridge (18). procedure after claim 20 , characterized in that the opening cross section (23) of the outlet opening (13) of the inlet connection (12) is released linearly, in particular uniformly, when the knife gate valve (10) is opened over the entire displacement path of the blocking device (16). Method for operating a knife gate valve (10), in particular according to one of claims 17 until 19 , for chemical and/or petrochemical industrial plants, in which the knife gate valve (10) comprises a valve housing (11) with an inlet connection (12) and an outlet connection (14) and a locking device (16) which is located in the valve housing (11) between a open position and a closed position for opening and closing the gate valve (10), the blocking device (16) having at least one blocking plate (17) and a pipe bridge (18) with a passage (26), which is arranged in the open position in such a way that the inlet connection (12) with an outlet opening (13) and the outlet connection (14) with an inlet opening (15) are connected to one another through the passage (26) of the pipe bridge (18). and the blocking device (16) is arranged in the closed position in such a way that the inlet connection (12) and the outlet connection (14) are blocked from one another by the blocking plate (17), the knife gate valve (10) having at least one guide device (19) for flow line, characterized in that the guiding device (19) has at least one guiding element (21') which is arranged between the shut-off plate (17) and the pipe bridge (18) in a displacement direction of the blocking device (16), the guiding element (21 ') forms a flow channel (32) transverse to the direction of displacement, which connects the inlet connector (12) to the outlet connector (14) when the blocking device (16) is moved from the closed position to the open position, before the passage (26) of the pipe bridge (18) releases an opening cross section (23) of the outlet opening (13) of the inlet connection (12). Use of a knife gate valve (10) according to one of Claims 1 until 16 and/or a knife gate valve (10) according to one of claims 17 until 19 in a coking process and/or a cracking process.

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