WO2001033126A1

WO2001033126A1 - Device for the torque-free operation of a closing member for a lift valve

Info

Publication number: WO2001033126A1
Application number: PCT/EP2000/010449
Authority: WO
Inventors: Willi Wiedenmann; Martin Sauer; Holger Wengert; Werner Schmid; Jens Burmester
Original assignee: Tuchenhagen Gmbh
Priority date: 1999-11-03
Filing date: 2000-10-24
Publication date: 2001-05-10

Abstract

The invention relates to a device for the torque-free operation of a closing member (2) for a lift valve (1). The construction of the inventive device is simple, whereby a simple actuator (11) is used. Said device enables to exchange the closing member (2) in an uncomplicated manner. To this end, the valve rod (3) is constantly configured as a hollow bar, is brought near to the closing component (2a) or to an axial extension (2a*) of the closing component (2a), whereby said extension is embodied in the direction of the actuator (11), and is directly or indirectly connected to the closing component (2a) or the extension (2a*) in a detachable manner or in a positive fit within a centrally arranged, axially oriented, cylindrical recess (3b; 3b, 3b*) and in such a way that the axes of the valve rod (3) and the closing component (2a) are in a coaxial alignment and that there is no degree of freedom of motion in the axial direction and that there is a relative degree of freedom of motion in the direction of circumference and between the valve rod (3) and the closing component (2a).

Description

Device for torque-free actuation of a closing member for a

globe valve

The invention relates to a device for the torque-free actuation of a closing member for a globe valve, in particular for one in which a bellows designed as a bellows or corrugated tube bridges a passage of a valve rod through the valve housing in such a way that it encloses the valve rod and on the one hand on a closure part of the closing member and, on the other hand, is directly or indirectly attached to the valve housing with an actuator which is detachably connected to the valve rod, in particular an actuator which, when acted upon by a pressure medium, carries out a lifting movement against the action of at least one return spring.

A device of the generic type can be found in EP 0 508 658 B1. There, the rotation of the valve rod, which would cause a corresponding rotation and thus additional stress on the bellows, the rotation being initiated by actuating the manual drive designed as a spindle / nut system, is prevented by an anti-rotation device provided in the area between the manual drive and the valve housing. The anti-rotation device in the present case consists of a wedge device arranged on the valve rod, which engages in a wedge sleeve. The wedge sleeve itself is fixed in the housing receiving it by suitable devices against rotation.

From DE 42 43 111 A1 an aseptic double-seat valve device is known, in which the bellows surrounding the valve rods are fastened at their two ends to two different components which, if only slightly, rotate relative to one another. In this context, it has already been recognized that the bellows, for example made of thin-walled stainless steel, are relatively sensitive to damage. They are stressed when opening and closing the valve plate on upsets or sections. If a further load is superimposed due to torsional stress type of claim, the bellows are exposed to an increased degree of risk of breakage. The torsional stress on the bellows results primarily from the twisting of the valve rods, which is to a small extent with each opening and closing stroke by an actuator which is used in the usual way and which, when acted upon by a pressure medium, performs a stroke movement against the action of at least one return spring executes, is caused. In such actuators, at least one helical spring is usually arranged, the respective ends of which execute a relative movement in the circumferential direction to one another during compression and stretching. This relative movement is transmitted to an associated piston which is under spring preload and which in turn is in engagement with the associated valve rod, so that the rotary movement is transmitted from the piston to the valve rod. To solve the problem it is provided in DE 42 43 111 A1 that those parts to which the bellows are attached are connected to one another in a rotationally fixed manner, with the result that torsion of the bellows is to be avoided. To produce the torsional strength of the parts involved, it is proposed, for example, to use a pin which secures the two valve plates against relative rotation and thus also the lower bellows against torsion. Similar measures are proposed for the upper bellows.

Another possibility for preventing the valve rod and thus the associated bellows from rotating is, for example, in the case of actuators which perform a lifting movement against the action of at least one return spring when a pressure medium is applied, to a rotationally fixed connection between the piston of the actuator and the associated valve rod to consciously forego. However, this requires additional constructive measures, which, however, cannot completely rule out the frictional forces between the parts that are now movable relative to one another in the circumferential direction, so that residual torques are transmitted from the actuator to the valve rod when the lift valve is actuated. In any case, the construction of the actuators becomes more complex due to the necessary measures to avoid torsional stresses that shorten the service life. An actuator which is very simple in construction, in which a piston rod, which is connected in a rotationally fixed manner to its piston, is detachably connected to the valve rod which is led out of the valve housing, is preferably used, for example, in aseptic valves, the typical representative of which, for example, in

DE 32 15 799 C2 is described. However, this publication does not show how the bellows is to be protected against torsional stress. In any case, no measures are disclosed between the actuator and the closing element - the actuator itself is not shown - which ensure a torque-free actuation of the closing element. The known aseptic valve, however, addresses a desirable property that such valves must have, namely the simple replacement of a closing member consisting of the closure part, bellows and connecting flange in the form of a so-called interchangeable replacement unit as a whole. In any case, such a requirement calls for a releasable connection between the valve rod and the closure part.

It is an object of the invention to provide a device of the generic type, which itself is also of simple construction using a simple actuator and which enables an uncomplicated replacement of the closing element.

The object is solved by the features of claim 1. Advantageous embodiments of the proposed invention are the subject of the dependent claims.

Due to the fact that the valve rod is brought up to the closure part or an axial extension thereof and is preferably directly or indirectly detachably connected to the closure part within a centrally arranged, axially oriented cylindrical recess, an uncomplicated replacement of the closing member becomes necessary, for example in the event of damage , possible. The main advantage, however, is that at the connection point between the closure part and the valve rod, which is necessary anyway, a swivel joint is also provided in good time. This configuration is achieved by a suitable positive connection between the closure part or its axial extension, which is shown in the direction of the actuator, and by means of which the axes of the valve rod and the closure part are aligned coaxially and by which there is no relative displacement in the axial direction and in the circumferential direction the valve rod and the closure part is possible. In other words, this means that there is no degree of freedom of movement in the axial direction and a relative degree of freedom of movement between the valve rod and the closure part in the circumferential direction. Because of this configuration, which is surprisingly easy to carry out at the intended location, a rotary movement of the valve rod resulting from the kinematics of the actuator is effectively kept away from the closing member and thus from the bellows. Furthermore, the use of a relatively simple standardized actuator is possible, the piston rod of which is non-rotatably connected to the piston and to which the valve rod which is led out of the valve housing can also be non-rotatably connected.

The invention can be implemented particularly simply if, as is proposed, the cylindrical recess is formed on the end of the valve rod on the closure part side.

A surprisingly simple and thus inexpensive solution is also achieved if a cylindrical extension is formed on the closure part or on its axial extension, which continues coaxially in alignment in a sleeve to which it is firmly connected by means of a screw connection. The cylindrical extension and the sleeve are each accommodated in the cylindrical recess with little play, and either the closure part or its cylindrical extension is in the axial direction via a stop surface formed on the valve rod and facing the closure part. The sleeve is fixed in a form-fitting manner in the cylindrical recess via a connecting means which engages radially both in a first circumferential groove in the valve rod and in a second circumferential groove in the sleeve. This determination is made in such a way that the sleeve is axially immovable towards the end of the cylindrical recess on the closure part side and axially displaceable in the opposite direction after loosening the screw connection between the sleeve and the closure part.

The arrangement of both the axial fixing between the closure part and the valve rod and the swivel joint formed at this point between the two components is generally possible without difficulty in the cylindrical recess if the cylindrical recess is formed in the end of the valve rod on the closure part, since for this area within the bellows For the valve rod designed as a hollow rod, a relatively large amount of space is available. The radial clearance required for the rotary joint can easily be realized between the sleeve and the cylindrical extension on the one hand and the cylindrical recess in the vent rod on the other. The positive connection between the sleeve and the valve rod end on the closure part is only released when the screw connection between the sleeve and the closure part is released and the sleeve is displaced in the only possible direction, namely away from the closure part, within the cylindrical recess. Such manipulation is only necessary if the sleeve is to be removed from the cylindrical recess. To replace the closing element, it is only necessary to loosen the screw connection between the sleeve and the closure part and to disassemble the closing element by pulling the cylindrical extension provided on the closure part out of the cylindrical recess from the valve rod.

A very simple positive connection between the sleeve and the valve stem with the desired properties is ensured according to another embodiment in that the connecting means is designed as a round wire snap ring.

If, as is provided in a further embodiment, the sleeve is made smaller in diameter than the cylindrical extension, so that an end face of the closure part or of the cylindrical extension protruding radially beyond the sleeve on the corresponding associated complete assembly executed on the valve rod end Meπtär abutting surface, then there are two advantages. On the one hand, the cylindrical extension can be sealed in an independent assigned cylindrical recess, on the other hand, there is an alternative inner stop surface in the direction in which the connecting means cannot transmit axial forces with respect to the sleeve, since the sleeve must be removable in the axial direction available, which, seen from the bellows, lies behind the seal and on which the necessary switching forces can be transmitted from the valve stem to the closing part when the closing element is closed. This presupposes that further possible stop surfaces between the valve rod end and the closure part or its axial extension are axially spaced such that a force transmission is not possible there.

In order to be able to solve the connection between the sleeve and the closure part and thus between the closing member and the valve rod in the simplest way, another embodiment provides that there is access to the screw connection between the sleeve and the closure part via a drive-side valve rod end of the valve rod. This is easily possible in that the valve rod is designed as a hollow rod and that the hollow rod bore provides access to the screw connection, which is preferably carried out by means of a so-called hexagon socket screw.

In order to protect and support the bellows from the inside, a further embodiment provides that the closed valve rod end edges the bellows with little radial play. The required diameter enlargement of the valve rod end on the closure part, on the other hand, creates on the inside the necessary space for accommodating the sleeve described above, for screwing it to the closure part and for the connecting means serving for the positive connection between the sleeve and the valve rod.

An embodiment of the invention is shown in the drawing and is described below. Show it 1 shows a central section through a preferred embodiment of the device according to the invention, wherein the entire lift valve and an adjacent lantern are completely cut and an actuator mounted on the lantern is partially cut, and FIG. 2 also shows a central section and in a large magnification in FIG "X" marked detail in the area of a connecting means designed as a round wire snap ring.

A globe valve 1 (FIG. 1) consists of a valve housing 1a with a first and a second housing connection 1b or 1c. In the valve housing 1a, a closing member 2 is arranged, which closes with its closure part 2a a passage opening, not specified, formed by the second housing connection 1c. The closure part 2a can consist of a single material or, as in the present case, of a first material component in the outer region and a second material component in the core region.

The closure part 2a or an axial extension 2a * formed in the direction of an actuator 11 is preferably detachably connected to the actuator 11 via a valve rod 3. An unspecified housing of the actuator 11 is supported by a lantern 7 on the Veπtügehäuse 1a. The actuator 11 is one whose piston 11a executes a lifting movement against the action of at least one return spring 11b when a pressure medium is applied to it. The piston 11a is preferably non-rotatably connected to a piston rod 11c, the valve housing end of which is preferably non-rotatably connected to the valve rod 3, which is designed as a hollow rod, on the drive-side valve rod end 3c. This connection between the valve rod 3 and the piston rod 11c can be provided inside the actuator 11 or outside it or in the area of the connection between the actuator 11 and the lantern 7. Within the valve housing 1 a bridged as a bellows 2b bridging the implementation of the valve rod 3 through the valve housing 1 a such that it encloses the vent rod 3 and on the one hand on the closure plate 2a of the closing member 2 and on the other hand indirectly via a connecting flange 2c in connection with a support ring 8 is fixed in the valve housing 1 a. Connection flange 2c, support ring 8 and the area of the valve housing 1a in question are fixed and held together by a flange of the lantern 7, which is not specified in any more detail, a clamping connection 9 (two complementary clamping flanges connected to an articulated clamp) being provided in the present case. The above-described stroke valve 1 corresponds to the state of the art and is also referred to as an aseptic lift valve in the illustrated embodiment.

The features of the invention are described below. The valve rod 3, which is designed as a hollow rod, is brought up to the closure part 2a and has a central, axially oriented cylindrical recess 3b there. A cylindrical projection 2d formed on the closure 2a is connected to a sleeve 4 such that the axis of the cylindrical projection 2d and that of the sleeve 4 are aligned coaxially. The latter has a central through bore 4a on the inside, via which the sleeve 4 is firmly screwed to the cylindrical projection 2d and thus to the closure part 2a by means of a connecting bolt 5, preferably a hexagon socket screw. The cylindrical extension 2d and the sleeve 4 are accommodated in the cylindrical recess 3b, each with little radial play. The sleeve 4 is positively fixed in the cylindrical recess 3b via a connecting means 6 which engages radially both in a first circumferential groove 3d in the valve rod end 3a on the closure part side and in a second circumferential groove 4b in the sleeve 4 (see also FIG. 2) ). This connecting means 6 is preferably a so-called round wire snap ring. The illustration clearly shows that the sleeve 4 is axially immovable in the direction towards the end of the cylindrical recess 3b on the closure part side and in the opposite direction, to the actuator 11 and only after loosening the Allen screw 5 from a nut thread 2e in the closure part 2a, is displaceable.

Since the vent rod 3 is designed as a hollow rod, there is access to the hexagon socket screw 5 via the drive-side valve rod end 3c, so that it can be tightened and also loosened from this side.

In order to protect and support the bellows 2b from the inside, the valve rod end 3a on the closure part side borders the bellows 2b with little radial play Δs. This radial expansion of the vent rod 3 in this area creates sufficient space for the installation of the sleeve 4, the round wire snap ring 6 and the hexagon socket screw 5.

Further details of the axially positive connection and in the tangential direction forming a swivel connection between the sleeve 4 screwed to the closure part 2a on the one hand and the valve rod end 3a on the other hand clarify FIG. 2. The round wire snap ring 6 is in the first groove formed in the valve rod end 3a 3d enclosed in a semicircle, so that here in both directions of movement of the valve rod 3 (opening or closing) there is a positive connection between the round wire snap ring 6 and the end of the valve rod 3a. The round wire snap ring 6, on the other hand, is bordered by the sleeve 4 in the second groove 4b only on a quarter circle facing away from the closure part 2a and immediately following the first groove 3d. This makes it clear that during the opening movement of the closing part 2a, initiated by the valve rod 3, a force Ö accompanying this opening movement from the closing part side valve rod end 3a onto the sleeve 4 and in connection with the cylindrical extension 2d (by means of the connecting bolt 5) onto the closing part 2a is transmitted. The reaction force Ö for this is based on the positive connection between the round wire snap ring 6 and the sleeve 4 in the region of the second groove 4 b. When the lift valve 1 closes, a closing force S to be transmitted from the valve rod 3 to the closure part 2a cannot be transmitted to the sleeve 4 via the round wire snap ring 6, since in this direction between the round wire snap ring 6 and the second groove 4b of the sleeve 4 there is no positive connection. Rather, the closing force S is supported in the exemplary embodiment shown via a stop surface 3e on the end face of the valve rod end 3a on the closure part on a complementary annular end surface 2f on the closure part 2a. If the sleeve 4 is made smaller in diameter than the cylindrical extension 2d, the aforementioned closing force S can alternatively also be applied via an inner end surface 2f ^{* of} the cylindrical extension 2d ^* projecting radially outwards beyond the sleeve 4, provided there is sufficient axial distance between the stop surface 3e and the annular end surface 2f a complementary inner stop surface 3e ^* , which is embodied in the region of the valve rod end 3a on the closure part and is radially inwardly recessed via the cylindrical extension 2d.

A smaller-diameter design of the sleeve 4 compared to the cylindrical projection 2d also creates the possibility of sealing the circumference of the latter in a cylindrical recess 3b * widened compared to the cylindrical recess 3b. In this way, for example, if the bellows 2b breaks, medium is prevented from reaching the interior of the valve rod 3 via the break point and from there via connecting paths (not specified in more detail) within the valve rod 3 and the adjacent lantern 7 into the environment. The seal between the cylindrical extension 2d and the valve rod end 3a on the closure part side is provided by a seal 10 arranged in the latter.

The assembly and disassembly of the connection between the locking member 2 and the valve rod 3 is as follows (Figures 1 and 2): When the arrangement is assembled for the first time, the sleeve 4 and the hexagon socket screw 5 therein are inserted into the cylindrical recess via the valve rod end 3a on the closure part side 3b inserted until the first groove 3d is exposed. Then the round wire snap ring 6 is inserted into the first groove 3d and the Sleeve 4 is pushed together with the hexagon socket screw 5 from the drive-side valve rod end 3c onto the round wire snap ring 6 until the sleeve 4 bears with the second groove 4b on the round wire snap ring 6. Now the closing member 2 can be pushed onto the valve rod end 3a on the closure part until the cylindrical projection 2d engages in the cylindrical recess 3b. The sleeve 4 and the closure part 2a are now firmly screwed together from the valve rod end 3c on the drive side by means of the Allen screw 5.

To replace the locking member 2, only a loosening of the screw connection between the sleeve 4 and the closure part 2a is required. The closing member 2 can now be pulled out of the cylindrical recess 3b via the cylindrical projection 2d formed on the closure part 2a. The sleeve 4 and the Allen screw 5 can remain unchanged in their position in order to be subsequently connected, for example, to another locking member 2.

The lantern 7 has at least one lantern opening 7a (FIG. 1), via which leaks, which can occur, for example, in the event of a defect in the bellows 2b and which take their way via the valve rod 3 designed as a hollow rod, are displayed and discharged into the environment. As a result, valve housing 1a and actuator 11 are clearly differentiated from one another within the scope of the applicable safety philosophy.

The lantern 7 also has at least two flushing and control connections 7b, via which the interior of the bellows 2b is monitored, flushed and any leakage that may occur can be displayed and removed. For better discharge of the leaks from the bellows folds and, if necessary, for better flushing of these areas, recesses 3f are provided in the outer jacket area of the valve rod end 3a, which engage into the area of the lower bellows folds. The solution proposed and shown in the exemplary embodiment enables assembly and disassembly of the closing member using simple standard tools. The lantern opening 7a to be covered with a transverse bore 3g in the valve rod 3 can be used to fix the valve rod 3 within the lantern 7 and thus within the valve housing 1a.

Claims

claims

1. Device for the torque-free actuation of a closing member (2) for a globe valve (1), in particular for one in which a bellows (2b) designed as a bellows or corrugated tube guides a valve rod (3) through the valve housing (1 a) in such a way bridged that it encloses the valve rod (3) and on the one hand is fastened directly or indirectly to a closure part (2a) of the closing member (2) and on the other hand to the valve housing (1 a), with an actuator (11) which is connected to the valve stem ( 3) is detachably connected, in particular an actuator (11) which, when acted upon by a pressure medium, carries out a lifting movement against the action of at least one return spring (11b), characterized in that the valve rod (3)

Is designed as a hollow rod throughout,

• up to the closure part (2a) or an axial continuation (2a ^* ) of the closure part (2a) which is formed in the direction of the actuator (11) and

• within a centrally arranged, axially oriented cylindrical recess (3b; 3b, 3b ^* ) directly or indirectly with the closure part (2a) or the continuation (2a *) and detachably connected in such a way that • the axes of the valve rod (3) and closure part (2a) coaxially aligned, and

• That there is no degree of freedom of movement in the axial direction and a relative degree of freedom of movement between the valve rod (3) and the closure part (2a) in the circumferential direction.

Device according to Claim 1, characterized in that the cylindrical recess (3b) is formed on the valve rod end (3a) on the closure part side.

3. Device according to claim 1 or 2, characterized in

That a cylindrical extension (2d) is formed on the closure part (2a) or its axial continuation (2a ^* ),

Which continues coaxially in alignment in a sleeve (4) with which it is firmly connected by means of a screw connection (5, 2e),

That the cylindrical extension (2d) and the sleeve (4) are each accommodated in the cylindrical recess (3b; 3b, 3b ^* ) with little radial play,

• That either the closure part (2a) or its axial continuation (2a ^* ) or the cylindrical extension (2d) via a stop surface (3e; 3e ^* ) facing the closing rod (3; 3a) and facing the closing part (2a) in the axial direction,

• That the sleeve (4) is positively fixed in the cylindrical recess (3b) via a both in a first circumferential groove (3d) in the valve stem (3; 3a) and in a second circumferential groove (4b) in the

Sleeve (4) each radially engaging connecting means (6),

• The sleeve (4) in the direction of the closure part end of the cylindrical recess (3b) axially immovable and

• in the opposite direction, after loosening the screw connection (5, 2e) between the sleeve (4) and the closure part (2a), is axially displaceable.

4. The device according to claim 3, characterized in that the connecting means (6) is designed as a round wire snap ring.

5. Apparatus according to claim 3 or 4, characterized in that the

Sleeve (4) is smaller in diameter than the cylindrical extension (2d), and that a radially over the sleeve (4) projecting end face (2f; 2f ^* ) of the closure part (2a) or the axial extension (2a ^* ) or the cylindrical extension (2d) rests on the corresponding complementary stop surface (3e; 3e *) on the valve rod (3; 3a).

6. Device according to one of claims 2 to 5, characterized in that for screwing (5, 2e) between the sleeve (4) and the closure part (2a) there is access via a drive-side valve rod end (3c) of the valve rod (3).

7. Device according to one of claims 1 to 6, characterized in that the closure part-side valve rod end (3a) borders the bellows (2b) with little radial play Δs.