EP4264097A1

EP4264097A1 - Throttle piston for reducing fluid pressure in a control valve

Info

Publication number: EP4264097A1
Application number: EP21839031.8A
Authority: EP
Inventors: Holger Eckholz
Original assignee: Samson AG
Current assignee: Samson AG
Priority date: 2020-12-17
Filing date: 2021-12-09
Publication date: 2023-10-25
Also published as: WO2022128715A1; CN220037497U; DE102020133949A1

Abstract

The invention relates to a throttle piston (1) for reducing fluid pressure in a control valve (100) from a high pressure region (104) to a low pressure region (103), the throttle piston (1) being translationally movable in an axial direction (A), defining a radial direction (R) transverse to the axial direction (A) and a circumferential direction (U) relative to the axial direction (A), and comprising a plurality of distribution chambers (11, 13, 21, 31), which are arranged in the interior (3) of the throttle piston (1) and are connected to each other by at least one transition channel (62, 64, 65), the distribution chambers (11, 13, 21, 31) comprising at least one high pressure distribution chamber (11, 13) and at least one low pressure distribution chamber (31), at least one inlet channel (41, 43) leading from the high pressure distribution chamber (11, 13) to a first throttle piston outer side (4) on the side of the high pressure region (104), and at least one outlet channel (51) leading from the low pressure distribution chamber (31) to a second throttle piston outer side (5) on the side of the low pressure region (105). According to the invention, the distribution chambers (11, 13, 21, 31) are offset relative to each other in the circumferential direction (U) and/or radial direction (R).

Description

Restrictor spool for reducing fluid pressure in a control valve

The invention relates to a throttle piston for reducing fluid pressure in a control valve for a process plant, such as a chemical plant, for example a petrochemical plant, a power plant, for example a nuclear power plant, a food processing plant such as a brewery, or the like. The throttle piston is configured to reduce fluid pressure from a high pressure region to a low pressure region, the throttle piston being translationally movable in an axial direction and defining a radial direction transverse to the axial direction and a circumferential direction related to the axial direction.

With a throttle piston, the potential energy (pressure) of a fluid can generally be converted into kinetic energy (high speed) and, by means of subsequent rapid deceleration (turbulence), converted into heat by friction and thus dissipated. However, not all of the kinetic energy is converted into heat. A certain proportion of this generates noise emissions, i.e. throttling noises, which, however, are associated with increased wear.

Flow restrictors are commonly used to protect control valve bodies and seats from excessive wear. Wear-promoting process conditions occur, for example, when very high local differential pressures occur at a valve. Very high local differential pressures are particularly problematic when there are large mass flows at the same time, and experience has shown that they are independent of the mass flow from a pressure gradient of around 20 bar upwards. Wear-promoting process conditions are also present in multi-phase flows if, in addition to a liquid phase, there is also a solid and/or a gas phase in the process fluid. Depending on the properties of the process fluid, in particular its vapor pressure, cavitation can occur in a process fluid line, which greatly increases wear and noise. However, cavitation can also occur when a multiphase flow is already present, for example in the form of a vaporous process fluid. If the process requires the fluid pressure to drop below its vapor pressure, this leads to what is known as "flashing operation", in which the process fluid is converted from a single-phase liquid state to a two-phase state with liquid and gas phases, whereby shock waves can also occur in addition to cavitation.

DE 1 650 196 A1 describes a liquid flow control element for high energy losses. A long, cylindrical plug is guided as a control element in a housing section so that it can slide axially back and forth. For shut off, a head portion of the controller plug is engageable with an annular control shoulder on a seat. In order to achieve energy losses in the flow medium, a plurality of long, low cross-sectional flow area, frictional suction energy loss channels are provided in the controller plug to divide the fluid flowing through the channel into a plurality of individual streams. The parallel channels can be formed by individual bores or bundled tubes. The individual energy loss channels extend from an area at the periphery to an area at the base end of the plug. High speed or pressure changes are not effected with the control element.

DE 2431 322 A1 discloses a control valve with a throttle body in the form of a perforated bush. The throttle body consists of a perforated bush with an H-shaped cross-section. Perforated disks are arranged in the perforated bush. The perforated discs are spaced apart from one another by spacer sleeves. The bottom spacer sleeve is slightly longer than the spacer sleeve above it, which ensures an increase in volume between the perforated disks in the flow direction of the medium. The holes arranged below the edge of the seat on the throttle body in the perforated bush have a diameter that increases with increasing distance from the edge of the seat. Likewise, the free one grows Cross-section of the holes arranged in the perforated discs from perforated disc to perforated disc in the flow direction of the medium. Depending on the stroke position, a different number of perforated discs are involved in throttling the medium pressure.

With the conventional shut-off and throttle valves, for example according to DE 1 650 196 A1 or DE 24 31 322 A1, a speed reduction is only possible when using lower pressure drops. For example, conventional gate and throttling valves exhibit extensive erosion phenomena at or near the throttling element and seat bore when subjected to a high pressure drop. Erosion caused by cavitating fluids can cause significant damage.

In order to achieve a pressure reduction that is as low-noise and low-wear as possible, multi-stage control valves are usually used in liquid applications above a certain differential pressure, as disclosed, for example, in WO 2019/152263 A1. Here, the differential pressure is distributed over several stages, so that the pressure drop across the respective stage remains below the critical value above which significant wear occurs or a permissible noise level is exceeded. As the number of stages increases, very high differential pressures can be reduced via the valve with little wear and noise. The pressure relief occurs at the orifice between the plug and the seat ring. Very high temperatures then occur at these points and the flow velocities are very high. Wear occurs on the plug and the seat ring. During maintenance work, the cone and seat rings then have to be replaced. Maintenance work is very often necessary, complex and expensive for valves with a large number of cones and seat bores with seat rings. Furthermore, throttle systems with several throttle elements connected in series require a large overall length, and the flow cross sections are greatly reduced over the individual stages, with the consequence of a significantly impaired mass flow.

It is an object of the invention to overcome the disadvantages of the prior art, in particular to improve a throttle body for reducing the fluid pressure in a process fluid line of a process plant such that with a compact design, the fluid pressure is greatly reduced even with a large flow volume is, wherein wear of the control valve, in particular due to cavitation, is largely avoided.

Accordingly, a throttle piston is provided for reducing fluid pressure in a control valve from a high-pressure area to a low-pressure area. The throttle piston is translationally movable in an axial direction and defines a radial direction transverse to the axial direction and a circumferential direction related to the axial direction. The throttle piston can preferably have a body with a cylindrical shape, with the cylinder axis corresponding to the translatory movement axis. The throttle piston comprises a plurality of distribution chambers which are arranged inside the throttle piston and which are connected to one another by at least one transition channel. No mixing chambers are preferably arranged on the outside of the throttle piston, in particular on a first and/or second outside of the throttle piston. In particular, the outer peripheral cylindrical sleeve shape of the throttle piston can be formed without a mixing chamber. The plurality of plenum chambers located inside the throttle piston include at least one high pressure plenum chamber and at least one low pressure plenum chamber. The throttle piston has at least one transition channel which fluidly connects at least exactly two mixing chambers or at least two mixing chambers to one another. A transition channel preferably connects several mixing chambers to one another in a fluidic manner. In particular, a mixing channel can fluidly connect two to 20, preferably three to ten, particularly preferably five to seven mixing chambers.

The throttle piston comprises at least one inlet channel, which leads from the high-pressure distributor chamber to a first, high-pressure area side of the throttle piston outside. The plurality of plenum chambers located within the throttle piston may include a plurality of high pressure plenum chambers. The throttle piston can have two, three or more inlet channels. In particular, a throttle piston has at least one high-pressure distribution chamber equipped with a plurality of inlet channels. It may be preferable for a throttle piston to be equipped with a number of inlet channels and a number of high-pressure distributor chambers, with each high-pressure distributor chamber having one or more inlet channels individually assigned to it. It may be preferred that the first throttle piston outside is a radially outside throttle piston peripheral side. Along the outside of the throttle piston, a plurality of high-pressure distribution chambers can be arranged offset relative to one another parallel to the first outside, in particular in the axial direction. The inlet channels can define a radial flow direction. Several hundred or several thousand, in particular 10 to 10,000, preferably 20 to 5,000, inlet channels can be provided on the first outside of the throttle piston

The throttle piston comprises at least one outlet channel, which leads from the at least one low-pressure distributor chamber to a second, low-pressure area-side throttle piston outside. The plurality of plenum chambers disposed within the throttle piston may include a plurality of low pressure plenum chambers. The throttle piston can have two, three or more outlet channels. In particular, a throttle piston has at least one low-pressure distribution chamber equipped with a plurality of outlet channels. It can be preferable for a throttle piston to be equipped with a plurality of outlet channels and a number of low-pressure distribution chambers, with each low-pressure distribution chamber having one or more outlet channels assigned individually to it. It can be preferred that the second throttle piston outside is an axial throttle piston end face. Along the second outside of the throttle piston, a plurality of low-pressure channels can be arranged offset relative to one another parallel to the second outside, in particular in the radial direction and/or circumferential direction. The outlet channels can define an axial flow direction. Dozens, in particular 10 to 10,000, preferably 20 to 2,000, outlet channels can be provided on the second throttle piston outside.

According to the invention, it is provided that the distribution chambers are offset relative to one another in the circumferential direction and/or in the radial direction. The throttle body has fluid-tight walls between different distribution chambers, which walls can be interrupted by one or more transition channels. The at least one transition channel is provided to form a bridge in the radial direction and/or the circumferential direction between one distribution chamber and another distribution chamber. In particular, between two or more adjacent distribution chambers are a corresponding number of in particular, at least as many transition channels are provided, which connect the two or more adjacent distribution chambers to one another. At least one transition channel is provided, which leads from a high-pressure distribution chamber to or in the direction of a low-pressure distribution chamber.

The throttle piston according to the invention preferably implements a labyrinth formed by the inlet channels, outlet channels, transition channels and distributor chambers. The pressure relief of the process fluid takes place almost exclusively within the labyrinth inside the throttle piston. This ensures an even pressure reduction. Furthermore, the inner flow cross sections are significantly less susceptible to wear than the area at an opening gap of conventional throttles between a valve cone and a valve seat. The reduction in pressure in the distribution chamber/channel labyrinth within the throttle piston avoids signs of wear, particularly on the valve seat and valve housing in the vicinity of the throttle piston. At the same time, the labyrinthine linking of several channels and distribution chambers allows a large part of the volume of the throttle piston body to be utilized and thus allows the use of a particularly space-saving control valve for significant pressure reduction.

According to one embodiment, the throttle piston further comprises at least one medium-pressure distributor chamber, which is connected to the high-pressure distributor chamber with a first transition channel and/or with the low-pressure distributor chamber with a second transition channel. In particular, no inlet or outlet channel leads directly from the medium-pressure distributor chamber to a first or second outside of the throttle piston. The distributor chambers arranged inside the throttle piston can comprise one or more medium-pressure distributor chambers. It should be understood that a medium pressure plenum is provided with at least two transition ducts, one of the transition ducts of the medium pressure plenum leading to or towards a high pressure plenum and the other of the transition ducts of the medium pressure plenum leading to or towards a Low pressure distribution chamber leads. At least one transition channel is provided, which leads from a high-pressure distribution chamber to a medium-pressure distribution chamber and/or from a medium-pressure distribution chamber to a low-pressure distribution chamber. In a throttle piston having numerous intermediate pressure plenums, a transition passage leads from a high pressure plenum to a first intermediate pressure plenum, a second transition passage leads from a low pressure plenum to a second intermediate pressure plenum, and further transition passages connect the at least two or more medium pressure distribution chambers inside the throttle piston. Multiple transition passages may be formed by a single throttle spool bore or similar tubular cavity extending transversely through the throttle spool and crossing multiple plenum chambers. The throttle piston may have at least one medium-pressure distribution chamber which is offset in the radial direction and/or circumferential direction with respect to at least one high-pressure distribution chamber and/or at least one low-pressure distribution chamber.

According to a preferred embodiment, the at least one high-pressure distribution chamber, in particular several high-pressure distribution chambers, and the at least one, in particular several, low-pressure distribution chambers are fluidly connected to one another by a three-dimensional network of transition channels. Inside the throttle piston, a labyrinthine, three-dimensional network of channels and optionally medium-pressure distribution chambers is formed, through which the process fluid can pave a path from the at least one inlet channel to the at least one outlet channel. The three-dimensional network is formed by a large number of crossing points of transition channels and distribution chambers, in particular medium-pressure distribution chambers. Figuratively speaking, the throttle piston can be penetrated like Swiss cheese by channels and distribution chambers, of which a part formed by inlet and outlet channels is connected to an outside of the throttle piston. A throttle piston with a three-dimensional network of transition channels and distributor chambers formed therein, in particular medium-pressure distributor chambers, shows excellent noise-damping and low-vibration properties, especially in the case of very high pressure differences between the high-pressure area on the first outside of the throttle piston and the low-pressure area on the second outside of the throttle piston. Furthermore, the use of a network of channels within the throttle piston allows permanent, low-maintenance operation, because individual defects within the network as a result of local Cavitation phenomena inside the throttle piston do not result in any noticeable impairment of the entire throttle valve. In particular, it has surprisingly been found that the occurrence of local cavitation phenomena within the throttle piston, unlike cavitation phenomena at an opening gap between the valve piston and valve seat of a conventional throttle valve, does not lead to exponential damage development with rapid valve failure.

According to a further development of a throttle piston according to the invention, which comprises several medium-pressure distributor chambers, which are located between the at least one high-pressure distributor chamber, in particular the several high-pressure distributor chambers, and the at least one low-pressure distributor chamber, in particular the several low-pressure distributor chambers, in the network of transition channels are involved, in particular third transition channels against each other offset medium-pressure distribution chambers fluidly connect with each other. The throttle piston may have at least two or more medium-pressure distribution chambers which are offset relative to one another in the radial direction and/or in the circumferential direction. The throttle piston can preferably have at least two medium-pressure distribution chambers which are offset in the radial direction and/or circumferential direction both relative to one another and relative to at least one high-pressure distribution chamber and/or relative to at least one low-pressure distribution chamber.

According to a further development, the mesh is formed from transition channels with an acute angle relative to the axial direction and from transition channels with an obtuse angle relative to the axial direction. An acute angle is generally between 0° and less than 90°. An obtuse angle is generally between more than 90° and 180°. The transition ducts can be divided into a first group of ducts sloping in a fan-like manner in the axial direction and a second group of ducts running in a fan-like manner against the axial direction. Contrastingly inclined transition channels or transition channel groups which cross one another are provided in the meshwork, with the crossing points in particular being realized in the medium-pressure distribution chambers. The two groups of transition channels can be arranged such that they are in one Diagonal cross-section through the throttle body form a net-like mesh together with the distribution chambers.

According to a further development, the distribution chambers have flow cross sections that deviate stepwise from the transition channels. The flow cross sections of the inlet channels are preferably smaller than the flow cross sections of the high-pressure distribution chambers. The flow cross sections of the outlet channels are preferably smaller than the flow cross sections of the low-pressure distribution chamber. The flow cross sections of the transition channels are preferably smaller than the flow cross sections of the high-pressure distribution chamber, low-pressure

distribution chambers and/or medium-pressure distribution chambers. Due to a cross-sectional shape of the channels and distribution chambers that differs in particular in steps, energy is dissipated at the many transitions between channels and distribution chambers by means of turbulence in the process fluid.

According to one embodiment, the distribution chambers are at least partially offset relative to each other in the axial direction. For example, a plurality of high-pressure distribution chambers can be arranged offset in the axial direction along the first outer surface. Alternatively, a plurality of low-pressure distribution chambers can be arranged offset in the axial direction along the second outer surface. The at least one medium-pressure distribution chamber can be offset in the axial direction relative to the at least one low-pressure distribution chamber and/or the at least one high-pressure distribution chamber. The at least two medium-pressure distribution chambers can be offset from one another in the axial direction. Preferably, the at least two medium-pressure distribution chambers are offset in the axial direction relative to at least one low-pressure distribution chamber, in particular relative to all low-pressure distribution chambers. The at least two medium-pressure distribution chambers are preferably arranged offset in the axial direction relative to at least one high-pressure distribution chamber.

According to one embodiment, at least one distribution chamber extends, ie at least one high-pressure distribution chamber, at least one medium-pressure distribution chamber, and/or at least one low-pressure distribution chamber, annular or spiral. Alternatively or additionally, at least one distributor chamber can extend partially or completely in the circumferential direction inside the throttle piston. A plurality of distribution chambers can preferably be ring-shaped or spiral-shaped and/or extend partially or fully around the inside of the throttle piston. The circumferential extension or annular shape is preferably rotational, in particular rotationally symmetrical, with respect to the axis of the throttle piston. For example, at least one distribution chamber can be toroidal. A plurality of distribution chambers are preferably ring-shaped over their entire circumference. In particular, all of the medium-pressure distribution chambers, all of the high-pressure distribution chambers and/or all of the low-pressure distribution chambers are annular in their entirety. In an embodiment with exclusively full-circumferential annular distribution chambers, the distribution chambers are at least partially offset relative to one another in the radial direction and optionally arranged at least partially offset relative to one another in the axial direction in the throttle piston.

According to a development, the high-pressure distribution chambers and the low-pressure distribution chambers are, in particular, ring-shaped over their entire circumference. In addition, the Mitteldmck distribution chambers can in particular be ring-shaped over the entire circumference. In particular, the distributor chambers are arranged coaxially to one another and, if appropriate, to the axis of the throttle piston. Starting with a radial or axial, taphole-like inlet channel on the first outside of the throttle piston, the use of at least one distribution chamber, in particular with a full circumference, can cause the process fluid to be distributed from one inlet channel over a larger volume area of the valve piston in order to create a large flow area for a provide a large amount of process fluid and to maximize the throttle volume provided for dissipation with respect to each individual inlet channel.

According to one embodiment of a throttle piston, several inlet channels lead from the same high-pressure distributor chamber to the first throttle piston outside. By two or more inlet channels lead into the same high-pressure distribution chamber, where the inflowing process fluid is deflected, the process fluid partial flows of the individual Inlet channels in the high-pressure distribution chamber are directed against each other to dissipate kinetic energy of the process fluid.

In a preferred embodiment, which can be combined with the previous embodiments, two inlet areas offset in the axial direction are arranged on the outside of the first throttle piston, with the inlet channels in the first inlet area having a smaller number and/or a smaller cumulative inlet cross section than the inlet channels in the second entry area. In particular, the first entry area and the second entry area can be of the same size in the axial direction and in the circumferential direction. In the case of a translational movement of the reciprocating piston in the axial direction, the first entry area can in particular first be released in order to provide a small flow cross section in an initial opening area, so that the flow rate can be finely metered. The second entry area can then be released to allow large flow rates.

According to a development, the first throttle piston outside forms a closed surface in the axial direction in front of the first and behind the second inlet area. The closed area in front of the first inlet area can include a section for preferably sealingly gripping a valve seat of the control valve. In particular, the section can have a tapering shape, in particular a rounded shape or an oblique shape, for example a truncated cone shape. The closed area behind the second inlet area can surround a mixing area of the throttle piston, in which at least one low-pressure distribution chamber, preferably several low-pressure distribution chambers, and optionally at least one medium-pressure distribution chamber, preferably a large number of medium-pressure distribution chambers, are arranged. By using a mixing region extending in the axial direction without inlet channels and without outlet channels, within which a large number of distribution chambers offset in the axial direction and in the radial direction and/or circumferential direction are arranged at least in pairs relative to one another, a large pressure reduction can be provided within a small throttle piston volume . According to one embodiment, several outlet channels led from the same low-pressure distributor chamber to the second throttle piston outside. An outer wall through which the outlet channels penetrate is arranged between the low-pressure distribution chamber and the outside of the throttle piston. The low-pressure plenum provides a receiving space in which transient fluid flows from preceding intermediate-pressure plenums and/or at least one high-pressure plenum may be directed toward one another.

In one embodiment of a throttle piston, which can be combined with the previous ones, the at least one outlet channel, in particular several outlet channels, leads to at least one outlet diffuser on the second throttle piston outside. The exit diffuser may be circular, annular and/or flower shaped. On the second outside of the throttle piston, a plurality of outlet diffusers, in particular arranged concentrically to one another, can be arranged. A diffuser can define an outlet cross section that widens conically in order to introduce the emerging fluid flow evenly into the low-pressure region of the control valve.

In particular, in one embodiment of the throttle piston, the inlet channels extend in the radial direction to a first throttle piston outside on the radial outer circumference of the throttle piston. The inlet channels are preferably aligned transversely to the axis of the throttle piston and/or transversely to their in particular annular high-pressure distribution chamber. Alternatively or additionally, the outlet channels extend in the axial direction from a second outside of the throttle piston on an axial end face of the throttle piston. The outlet channels are preferably aligned parallel to the axis of the throttle piston and/or transversely to their low-pressure distribution chamber, which is in particular annular.

According to the invention, a control valve is provided for a process plant, for example a chemical plant such as a petrochemical plant, a power plant, for example a nuclear power plant, a hydrothermal power plant or the like, or a food processing plant such as a brewery. The control valve includes a high-pressure area for receiving a process fluid at a first pressure level and a low-pressure area for discharging the process fluid at a second pressure level below the first pressure level. The pressure difference between the first pressure level and the second pressure level is operationally at least 10 bar, preferably at least 20 bar, in particular more than 30 bar. The control valve also includes a valve housing, which defines a cross section through which flow can take place from an inlet to an outlet, and a valve seat formed on the valve housing and arranged between the high-pressure area and the low-pressure area. Furthermore, the control valve comprises a throttle piston according to the invention guided in the valve seat. The throttle piston according to the invention preferably cooperates with the valve seat. The throttle piston is arranged to be movable in the axial direction relative to the valve housing, in particular the valve seat. In particular, the throttle piston can be movable between a first closed position, in which a closing area, in particular a conical section, of the throttle piston cooperates in a sealing manner with a valve seat, and a second flow position, in which all inlet channels and outlet channels of the throttle piston are blocked from the valve housing, in particular the valve seat and/or a valve cage, are released. The throttle piston can be set up to assume one or more intermediate positions between the closed position and the flow position, a different number of inlet channels and/or outlet channels being released depending on the position of the throttle piston in the respective intermediate position in relation to the valve housing. The flow rate of the process fluid through the control valve with the throttle piston can be adjustable depending on the number of released inlet channels and/or outlet channels.

The throttle piston is preferably to be accommodated in the process plant according to a so-called “flow-to-close” (FTC) flow direction, with the inlet channels being arranged on a radial outer circumference of the throttle piston and the outlet channels on an axial end face of the throttle piston. With the FTC valve, the number or cumulative entry area of the released entry channels is decisive for the flow rate. Alternatively, the control valve can be accommodated in the process plant according to a so-called “flow-to-open” (FTO) flow direction, with the inlet channels being arranged on an axial end face of the throttle piston and the outlet channels on a radial peripheral side of the throttle piston. In which FTO valve, the number or cumulative outlet area of the released outlet channels is decisive for the flow rate.

Further properties, advantages and features of the invention become clear from the following description of preferred embodiments of the invention with reference to the accompanying drawings, in which:

FIG. 1 shows a schematic cross-sectional view of a control valve with a throttle piston according to the invention in a flow position;

FIG. 2 shows a schematic cross-sectional view of a throttle piston according to the invention;

FIG. 3 shows a plan view of an axial end face of the throttle piston according to the invention according to FIG. 2;

FIG. 4 shows a perspective view of the throttle piston according to the invention according to FIG. 2;

FIG. 5 shows a schematic cross-sectional view of the control valve according to FIG. 1 in an intermediate position;

FIG. 6 shows a schematic cross-sectional view of the control valve according to FIG. 1 in a closed position; and

FIG. 7 shows a schematic cross-sectional view of another control valve.

In the following description of preferred embodiments based on the figures, the same or similar reference numbers are used for the same or similar components of different embodiments. A throttle piston according to the invention is generally given the reference number 1 . The throttle piston 1 according to the invention comprises inlet channels 41, 43, high-pressure distributor chambers 11, 13, transition channels 62, 64, 65, low-pressure distributor chambers 31 and outlet channels 51.

As can be seen in FIG. 1, the throttle piston 1 can be installed in a control valve 100 during operation. The control valve 100 is provided for the installation of a process engineering system in the flow direction flow-to-close (FTC) according to the arrow shown.

The control valve 100 has a housing 103 which surrounds the process fluid-carrying interior. The process fluid-carrying interior of the control valve 1 can be divided into the high-pressure area 104, the low-pressure area 105 and the area of the valve seat 101. In the first embodiment of a control valve 100 according to FIGS Coaxial mounting flanges are provided for connecting inflow or outflow pipes. The flow direction of the process fluid through the control valve 100 corresponds to the radial direction R.

In the embodiment of a control valve 100 according to FIG. 7, the directions of flow at the inlet area 104 and at the outlet area 105 are aligned transversely relative to one another. The flow in the low-pressure area 105 runs parallel to the axial direction A and the flow in the high-pressure area 104 in the radial direction R.

In the context of the present description, the valve seat 101 is considered to be part of the valve housing 103 . It is clear that the valve seat 101 can be an individual part that can be detached from the rest of the valve housing 103 . When the control valve 100 is in its operational state of use, the valve seat 101 is firmly connected to the rest of the valve housing 103 . The valve housing 103 has a cover formed as a lantern 107 in the axial direction A above the valve seat 101 . A particularly pneumatic or electric actuating actuator 109 is attached to the lantern 107 and is connected to the throttle piston 1 in terms of force transmission by means of the actuating rod 111 . A relative position of the throttle piston 1 in relation to the valve housing 103 can be set by actuating the setting actuator 109 . Figure 1 shows the throttle piston 1 in a flow position in which all inlet channels 41, 43 are released. Figures 6 and 7 show a closed position of the throttle piston 1 in the respective control valve 100. Figure 5 shows an intermediate position of the throttle piston 1 in the control valve 100, in which a number of inlet channels 43 are closed by the valve seat 101 and to which a few inlet channels 41 are released. In each control state of the throttle piston 1 in the control valve 100 according to FIG. 1, FIG. 5 or FIG.

The throttle piston 1 is described below with reference to FIGS. The throttle piston 1 has a generally cylindrical shape, which defines an axial direction A and a radial direction R transverse thereto, as well as a circumferential direction U related to the axial direction A. Since the throttle piston 1 is essentially rotationally symmetrical, there is no need to distinguish between different radial directions to be hit. Inlet channels 41 , 43 projecting into the interior of the throttle piston 1 and outlet channels 51 leading out of the throttle piston 1 are arranged on two different outer sides 4 , 5 .

In the present exemplary embodiments, according to the process fluid flow direction FTC, the designation inlet channels 41, 43 is selected for the channels extending in the radial direction R from the first, radial peripheral outside 4 into the interior of the throttle piston 1. Correspondingly, for the exemplary embodiments shown here according to the process fluid flow direction FTC, the designation outlet channels 51 is chosen for the channels extending in the axial direction A from the second, axial end face outside 5 into the interior of the throttle piston 1 . The designation inlet channels 41, 43 or outlet channels 51 is chosen within the scope of the present disclosure for easier comprehension with reference to the preferred flow direction shown in the figures. It is clear that, depending on the direction of flow of the process fluid, in an alternative embodiment (not shown in detail) the radial channels would be implemented as outlet channels and the axial channels as inlet channels. The throttle piston 1 can be formed, in particular as a one-piece body 3, preferably from a solid material. The body 3 of the throttle piston 1 is penetrated by a network 6 of channels and distribution chambers. The process fluid can flow through the throttle piston 1 through the labyrinthine network 6 of distribution chambers and channels. A solid body 3, which is traversed by a chamber and channel network 6 with numerous undercuts, can be produced, for example, by an additive manufacturing process, such as a 3D printing process, a sintering process or the like.

On the first, radial outside 4 of the throttle piston 1, inputs for the various input channels 41, 43 are provided. The radial outside 4 of the throttle piston 1 can be divided into different areas, as will be described with reference to FIG. On the uppermost part of the throttle piston 1 in the axial direction A, a closure area is formed by a closed surface 10 on which a frustoconical projection is provided for sealing engagement with a valve seat 101 of the control valve.

Adjacent to the closure area 10 in the axial direction A, the throttle piston 1 has a first, progressive inlet area 40 with first inlet channels 41. The density of inlet channels 41 increases in the first inlet area 40 in the axial direction A, ie the inlet channel increases with increasing distance from the closure area 10 -Density. The density of inlet channels 41 can be increased in the axial direction A to a maximum. Further inlet channels 43 are provided in a second, constant inlet area 42 which adjoins the first inlet area 40 in the axial direction A. In the second entry area 42 there is a high, in particular the maximum, entry channel density. The number of inlet channels 41 or 43 in a section of the throttle body 1 in the axial direction A can be referred to as inlet channel density. By providing the throttle body 1 with a first inlet area 40 with increasing channel density and a second inlet area 42 with a higher channel density, a throttle body 1 can be implemented which, on the one hand, allows high flow rates when both inlet areas 40, 42 are released, and, on the other hand, precise dosing low flow rates allowed if only a first entry area 40 low channel density is released, in particular only partially. Alternatively, a throttle body can be designed with only a constant or progressive entry area (not shown).

In the axial connection to the entire inlet area, the throttle body 1, as shown here, can be designed with a second closed surface 50, which extends in the axial direction A. In the area of the second closed surface 50, a mixing area with numerous distribution chambers 21, 31 and transition channels 62 can be formed inside the throttle body 3. In particular, a large number of medium-pressure distribution chambers 21 can be provided in the area of the closed surface 50, which are not directly connected to the high-pressure area 104 or the low-pressure area 105 either by inlet channels 41, 43 or by outlet channels 51. The medium-pressure distributor chambers 21 are connected to one another and to the high-pressure distributor chambers 11, 13 and the low-pressure distributor chambers 31 only via transition channels 62, 64 and 65. By using several medium-pressure distribution chambers 21, a large number of process fluid flow crossing points are realized inside the body 3 of the throttle valve 1, at which energy of the process fluid can be dissipated in order to create a large pressure gradient between the high-pressure area 104 and the low-pressure area 105 set. Even if a cross point inside the throttle valve body 3 is damaged due to cavitation or the like, the other cross points remain unaffected. As a result, the throttle piston 1 can be used maintenance-free for a long time. Damage to the valve seat 101 is practically completely avoided

At the lower end of the throttle piston 1 in the axial direction A, the second outer side 5 is formed, at which a large number of outlet channels 51 open into a number of outlet diffusers 53 . The lower outside 5 or end face of the throttle piston 1 is shown in FIG. A circular, central outlet diffuser 53 is provided in the center of the lower outside 5 and is coaxially surrounded by five ring-shaped outlet diffusers 53 . Several, different numbers of outlet channels 51 each open into the various outlet diffusers 53. The number of outlet channels 51 per diffuser 53 increases with increasing radial distance from the axis of the throttle piston 1. The use of the outlet diffusers 53 ensures that the gas emerging from the throttle piston 1 in the axial direction A Process fluid flow is discharged homogeneously in the low-pressure region 105 of the control valve 100 in order to protect the valve housing 103.

As can be seen in FIGS. 1 and 2, the network of channels and chambers 6 forms a three-dimensional, multiply linked network structure inside the body 3 of the throttle piston 1 . From the first, radial outside 4 of the throttle piston 1, the inlet channels 41 and 43 lead to the high-pressure distributor chambers 11, 13. In the first inlet area 40, based on the total number of inlet channels 41 and 43, there are relatively few inlet channels 41 that are long in the radial direction R . The long inlet channels 41 lead to high-pressure distribution chambers 11 at a relatively large distance from the radial outside 4 or a short distance from the axis A. Energy from the process fluid flow can be absorbed in the long inlet channels 41 by wall friction. The first inlet channels 41 are surrounded by relatively thick channel walls formed by the body 3 with a correspondingly high thermal mass.

In the second entry area 42 there is a very high number of entry channels 43 in relation to the total number of entry channels 41 and 43, so that a large cumulative flow cross section can be realized. The second inlet channels 43 in the second inlet area 42 are very short and lead to high-pressure distributor chambers 13 close to the radial outside 4 of the throttle body 1. In the short second inlet channels 43 there is little wall friction. In the second entry area 42, the individual, full-circumferential toroidal high-pressure distribution chambers 13 are each equipped with a large number of entry channels 43, so that the fluid flow flows into the high-pressure distribution chamber 13 in a wide variety of entry directions and partial flows are oriented in opposite directions in the individual high-pressure distribution chambers and set up plenty of turbulence to dissipate energy of the process fluid.

The various high-pressure distribution chambers 11 and 13 of the throttle piston 1 are arranged in the body 3 of the throttle piston 1 at least partially offset relative to one another in the radial direction and axial direction A. It is conceivable that, in particular in the second entry area 42, a plurality of high-pressure distribution chambers 13 only in the axial direction A relative are offset to each other. In the exemplary embodiment shown here, the inlet channels 41, 43 have a teardrop-shaped cross section that tapers upwards. Alternatively, the channels 41, 43 can at least partially have a rhombic, triangular, oval and/or round cross-sectional shape. It is clear that the inlet channels 41, 43 can have a different cross-sectional shape. Alternatively or additionally, the inlet channels 41, 43 may have the same or different cross-sectional shape and size other than the oval shown. The individual inlet channels 41, 43 can be designed in a straight line or in the manner of a labyrinth, cascade or helical channel or completely freely.

The process fluid can flow from the high-pressure distribution chamber 13 into other high-pressure distribution chambers 13 through transition channels 65 on the inlet side, which can stimulate additional vortex formation. In particular, the process fluid can flow from the high-pressure distribution chambers 11, 13 through transition channels 65 on the inlet side into the first medium-pressure distribution chambers 21. A large number of transition channels 65 can be formed between the medium-pressure distribution chambers 21 and the high-pressure distribution chambers 11, 13, so that process fluid flow can flow into the medium-pressure distribution chambers 21 with the most varied of orientations, resulting in further oppositely directed flows and turbulences in the Medium-pressure distribution chambers 21 result.

Inside the throttle piston 1, a multiplicity of different medium-pressure distribution chambers 21 are provided. The medium-pressure distribution chambers 21 can be tom-shaped over their entirety. In the throttle piston 1, several or exclusively partial distribution chambers, ie high-pressure distribution chambers 11, 13, low-pressure distribution chambers 31 and/or medium-pressure distribution chambers 21, can be formed. A part-circumferential distribution chamber can, for example, be in the form of a ring section. A part-circumferential chamber is provided with at least two, preferably more than two, channels, at least one of which leads towards the first outer side 4 and at least another towards the second exit side 5 . For example, in the throttle piston, several distribution chambers can be provided which are adjacent in the circumferential direction 4 and are separated from one another by radial walls which are not, partially or all of transition channels in Circumferentially penetrated. A plurality of medium-pressure distribution chambers 21 can surround one another coaxially with the axis A of the throttle piston in an axial plane. Different medium-pressure distribution chambers 21 can be arranged offset relative to one another in the axial direction A in different axial planes. Adjacent axial planes can be arranged in the body 3 of the throttle piston 1 with or without axial height overlap.

In the throttle piston 1 shown in FIG. 1, six different tiers with medium-pressure distributor chambers 21 are formed one above the other in the axial direction A. A further floor with a first high-pressure distribution chamber 11 is arranged above it in the axial direction A. The top floor consists of a single full-circumference, tom-shaped high-pressure distribution chamber 11. Instead of a single full-circumference tom-shaped high-pressure distribution chamber 11, it is conceivable that no more than one or, for example, no more than two of the first inlet channels 41 open into partial-circumference high-pressure distribution chambers 11 . According to the sectional view shown in FIG. 1, three high-pressure distribution chambers 13 are provided in three corresponding axial tiers in the second entry area 42 . Each of the full-circumference high-pressure distribution chambers 13 surrounds a plurality of medium-pressure distribution chambers 21 formed on the same floor.

An additional floor with all the low-pressure distribution chambers 31 is arranged below the medium-pressure distribution chambers 21 . The low-pressure plenum chambers 31 are connected to the bottom tier of medium-pressure plenum chambers 21 with second transition ducts 62 . Starting from the low-pressure distribution chambers 31, the outlet channels 51 lead to the outlet diffusers 53. In the exemplary embodiment shown here, the outlet channels 51 have an oval cross section. It is clear that the outlet channels 51 can have a different cross-sectional shape. Alternatively or additionally, the exit channels 51 may have the same or different cross-sectional shape and size other than the oval shown. The individual outlet channels 51 can be designed in a straight line or in the form of a labyrinth, cascade or helical channel or completely freely.

As can be seen, for example, in FIGS. 1 and 2, the transition channels 62, 64 and 65 together with the distribution chambers 11, 13, 21 and 31 form a mesh 6. The Transition channels form a network-like structure which has its crossing points at the distribution chambers. The transition channels can be divided into 2 different groups, namely a first channel group which is arranged at an acute angle with respect to the axis A and a second group which is arranged at an obtuse angle with respect to the axis A, so that the braid 6 with the in Figure 1 forms the diamond-shaped network structure shown.

In the embodiment shown here as an example, the transition channels are designed in coaxially aligned subgroups that extend diagonally through the body 3 of the throttle piston 1 (similar to through bores, apart from the fact that the subgroups in the exemplary embodiment shown in Figure 1, for example, without the inlet opening of a typical bore are formed). As shown here as an example, the transition channels 62, 64, 65 can all have the same, constant cross-sectional shape and size. The flow cross section of the distribution chambers 11, 13, 21, 31 is larger than the cross section of the channels 41, 43, 51, 62, 64, 65. In this way, steps are formed, which promotes the dissipation of energy of the process fluid. It is clear that the transition channels can have different and/or variable cross-sectional shapes. The individual transition channels can be designed in a straight line or in the form of a labyrinth, cascade or helical channel or completely free.

The features disclosed in the above description, the figures and the claims can be important both individually and in any combination for the implementation of the invention in the various configurations.

Reference sign

1 throttle piston

3 bodies

4 first outside

5 second outside

6 braid

10 closed area

11, 13 high pressure plenum

21 Medium pressure distribution chamber

31 Low-pressure manifold chamber

40 first entry area

42 second entrance area

41, 43 entry channel

50 closed area

51 exit channel

53 exit diffuser

62, 64, 65 transition channel

100 control valve

101 valve seat

103 valve body

104 high pressure area

105 low pressure area

107 Lantern

109 actor

A axial direction

R radial direction

U longitudinal direction

Claims

24 claims

1. Throttle piston (1) for reducing fluid pressure in a control valve (100) from a high-pressure region (104) to a low-pressure region (105), the throttle piston (1) being translationally movable in an axial direction (A) and a radial direction (R) defined transversely to the axial direction (A) and a circumferential direction (U) related to the axial direction (A), comprising a plurality of distributor chambers (11, 13, 21, 31) arranged inside the throttle piston (1), which are connected by at least one transition channel (62, 64, 65) are connected to one another, with the distributor chambers (11, 13, 21, 31) comprising at least one high-pressure distributor chamber (11, 13) and at least one low-pressure distributor chamber (31), with at least one inlet channel (41, 43) from the high-pressure distribution chamber (11, 13) to a first, high-pressure area (104) side

outside (4) of the throttle piston and wherein at least one outlet channel (51) leads from the low-pressure distribution chamber (31) to a second outside (5) of the throttle piston on the low-pressure area (105) side, characterized in that the distribution chambers (11, 13, 21, 31) are offset relative to one another in the circumferential direction (U) and/or radial direction (R).

2. Throttle piston (1) according to claim 1, further comprising at least one medium-pressure distributor chamber (21) with a first transition channel (64) with the high-pressure distributor chamber (11, 13) and / or with a second transition channel (65). is connected to the low-pressure distribution chamber (31), in particular no inlet or outlet channel leading directly from the medium-pressure distribution chamber (21) to a first or second throttle piston outside (4, 5). Throttle piston (1) according to Claim 1 or 2, comprising at least one, in particular several, high-pressure distribution chambers (11, 13) and at least one, in particular several, low-pressure distribution chambers (31), which are formed by a three-dimensional network of transition channels (62, 64, 65) are fluidically connected to one another. Throttle piston (1) according to claims 2 and 3, further comprising a plurality of medium-pressure distribution chambers (21) between the high-pressure distribution chamber (11, 13), in particular the plurality of high-pressure distribution chambers (11, 13), and the low-pressure distribution chamber (31), in particular the several low-pressure distribution chambers (31), are integrated into the network of transition ducts (62, 64, 65), with third transition ducts (62) in particular fluidly connecting medium-pressure distribution chambers (21) that are offset relative to one another. Throttle piston (1) according to claim 3 or 4, wherein the mesh is formed from transition channels with an acute angle relative to the axial direction (A) and transition channels with an obtuse angle relative to the axial direction (A). Throttle piston (1) according to one of claims 3 to 5 , wherein the distributor chambers (11, 13, 21, 31) have flow cross sections which deviate stepwise from the transition channels (62, 64, 65). Throttle piston (1) according to one of the preceding claims, in which the distribution chambers (11, 13, 21, 31) are at least partially offset relative to one another in the axial direction (A). Throttle piston (1) according to one of the preceding claims, wherein at least one distribution chamber (11, 13, 21, 31) is ring-shaped or spiral-shaped and/or extends partially or completely inside the throttle piston (1) in the circumferential direction (U). . Throttle piston (1) according to claim 8, wherein the high-pressure distribution chamber (11, 13) and the low-pressure distribution chamber (31) and optionally the medium-pressure distribution chamber (21) are ring-shaped, the distribution chambers being in particular arranged coaxially. Throttle piston (1) according to any one of the preceding claims, wherein at the first

Throttle piston outside (4) arranged two axially offset inlet areas (40, 42). are, wherein the inlet channels (41) in the first inlet area (40) have a smaller number and/or a lower cumulative inlet cross-section than the inlet channels (43) in the second inlet area (42). Throttle piston (1) according to claim 10, wherein the first throttle piston outer side (4) in the axial direction (A) in front of the first and behind the second inlet area (40, 42) forms a closed surface (10, 50), in particular the closed Surface (50) behind the second inlet area (42) surrounds a mixing area of the throttle piston (1), in which at least one low-pressure distributor chamber (51) and optionally at least one medium-pressure distributor chamber (21) is arranged and/or the closed surface in particular (10) in front of the first inlet region (40) comprises a section for preferably sealingly gripping a valve seat (101) of the control valve (100). Throttle piston (1) according to one of the preceding claims, wherein the at least one outlet channel, in particular several outlet channels (51), lead to at least one outlet diffuser (53) on the second throttle piston outside (5), the outlet diffuser (53) in particular being circular, ring-shaped or flower-shaped. Control valve (100) for a process engineering system, comprising a high-pressure area (104) for receiving a process fluid at a first pressure level, a low-pressure area (105) for dispensing the process fluid at a second pressure level below the first pressure level, a high-pressure area (104) and a low-pressure area between (105) arranged valve seat (101) and in the valve seat (101) arranged throttle piston (1) according to any one of the preceding claims.