WO1994023226A1

WO1994023226A1 - Ball- or plug-type control valve

Info

Publication number: WO1994023226A1
Application number: PCT/FR1994/000357
Authority: WO
Inventors: Noël CATIN
Original assignee: Catin Noel
Priority date: 1993-03-30
Filing date: 1994-03-30
Publication date: 1994-10-13
Also published as: FR2703423A1; FR2703423B1

Abstract

A ball- or plug-type control valve (10) comprising a valve body (11) defining a housing (12) for a sealing member (13) designed to define a communication passage (13') between an inlet and an outlet when the valve is in the open position, and to seal said passage when the valve is in the closed position. The sealing member (13) consists of a fluid-inflatable elastomeric pocket (16). When the valve (10) is in the open position, the pocket (16) is deflated, and when the flow through the valve is to be controlled, the pocket (16) is inflated to a greater or lesser degree by varying the pressure of the fluid fed in through a fluid supply channel (18). At pressures higher than a given pressure, said pocket (16) completely seals off the passage between the inlet and the outlet, thus closing the valve. Said valve may be used with material-loaded, fouling, crystallising and pulverulent fluids.

Description

BALL OR BALL VALVE REGULATION VALVE

The present invention relates to a ball or plug type control valve having a body defining a housing for a closure element arranged to define a communication passage between an inlet pipe and an outlet pipe when the valve is in open position and to close this passage when the valve is in the closed position.

There are currently various devices for regulating or cutting the passage of a fluid in a conduit. The devices commonly used are direct flow valves, "butterfly" type valves and ball valves. However, when the fluids flowing through these devices are charged, clogging, crystallizing or pulverulent fluids, various problems arise.

In the case of the passage of a fluid loaded with waste through a direct passage valve, it frequently happens that a solid particle remains trapped in the valve cover. It is then no longer possible to place the shutter in an adequate position and the valve is no longer sealed. In addition, the valve mechanism is located in the fluid stream and therefore is particularly stressed and therefore becomes very vulnerable.

In the case of a "butterfly" type valve, a pivoting shutter opens or closes the passage between a conduit and an outlet conduit. When the valve is in the open position, the shutter is located in a fluid stream. It is therefore subject to significant abrasion if the fluid is not free from all particles, and no longer seals the valve after a relatively short time of use. In addition, this shutter causes turbulence, which erodes the seat and creates significant pressure losses. When using ball valves, when closing the valve, the fluid is inserted between the sphere and the seat. This quickly leads to a loss of tightness. In addition, when it is desired to use this type of valve as a control valve, swirls and particularly large pressure drops occur. This results in fatigue which can lead to rupture of the valve, vibrations which cause premature wear and a noise which can be unpleasant.

All these faults require frequent valve changes, which results in significant loss of time and money.

The ideal valve for applications using fluids as mentioned above should have the following characteristics:

- offer an absolutely free passage to avoid abrasion and clogging;

- have no moving mechanical parts in the fluid;

- Include a sealing element to obtain the seal without it deteriorating even if there are solid particles inside the valve;

- do not allow any contact between the fluid and the body.

The present invention proposes to overcome the drawbacks cited with reference to conventional valves by proposing a valve having the characteristics described above.

This object is achieved by a valve as defined in the preamble and characterized in that the closure element is equipped with at least one inflatable pocket using a pressurized fluid, so as to pneumatically close said passage. Communication.

According to the preferred embodiment, the inflatable bag is made by means of an airtight and fluid-tight etastomer material crossed by the valve. Said waterproof elastomeric material is preferably formed from several textured layers.

According to the preferred embodiment, the inflatable bag is connected to a conduit for supplying the inflation fluid passing through the closure element.

Advantageously, the inflatable pocket has an interior part of substantially cylindrical shape whose diameter is substantially equal to the diameter of said communication passage and the ends of said pocket are fixed to said closure element on either side of this passage.

According to a first embodiment, the ends of the pocket are fixed to said closure element by means of two rings arranged on either side of said closure element.

According to a second embodiment, the ends of the pocket are fixed to said closure element by means of two lateral rings arranged on either side of a central part, said lateral rings being fixed by means of screws to said part. central.

According to a third embodiment, the elastomeric material completely surrounds the ball or the plug, while leaving a communication passage between the inlet conduit and the outlet conduit, and by defining an inflatable pocket disposed in said communication passage. In this embodiment, the valve advantageously comprises two conduits for supplying the inflation fluid, one of these conduits passing through the ball or the plug and opening into a part of the inflatable bag located in the communication passage, the other conduit opening into part of the inflatable bag in contact with the valve body.

According to a fourth embodiment, the valve includes an interior insert engaged in the communication passage and covered with a cylinder of elastomeric material forming said inflatable pocket.

Said interior insert advantageously comprises at least one opening connected to the inflation fluid supply duct, this opening being arranged to allow the introduction of the fluid into said inflatable pocket. Said insert preferably comprises an external thread arranged to cooperate with an internal thread of the closure element.

The present invention and its advantages will appear better in the description of exemplary embodiments with reference to the accompanying drawings in which:

Figure 1 is a sectional view of a first embodiment of a ball valve according to the present invention in the open position;

Figure 2 is a sectional view of the valve of Figure 1 in the regulation position;

Figure 3 is a sectional view of the valve of Figure 1 in the closed position;

Figures 4 and 5 are sectional views of a second embodiment of a valve according to the present invention respectively in the open and closed position;

Figures 6 and 7 are sectional views of a third embodiment of a valve according to the present invention respectively in the open and closed position;

Figures 8 and 9 are sectional views of a fourth embodiment of a valve type valve according to the present invention respectively in the open and closed position;

Figure 10 is a sectional view of a fifth embodiment of a valve according to the present invention in the open position with vacuum;

Figure 11 is a sectional view of the valve of Figure 10, in the open position, at normal pressure; Figure 12 is a sectional view of the valve of Figure 10, in the closed position, with overpressure; and

Figure 13 is a sectional view of a sixth embodiment of a valve according to the present invention.

Figures 14 and 15 illustrate an alternative embodiment in section, of which a half-section illustrates the uninflated position of the bag while the other section illustrates the inflated position, Figure 14 showing the valve in one of its positions while that Figure 1 shows the other of the positions.

FIG. 16 illustrates an alternative embodiment of the insert.

Referring to Figures 1 to 3, the valve (10) comprises a body (11) defining a housing (12) in which is placed a closure element (13) comprising a communication passage (130 between an inlet duct (1) and an outlet duct (2). This closure element (13) is represented in this example in the form of a spherical ball. It comprises a central part (14) and two lateral rings (15) and (150 as well as an inflatable pocket (16). This pocket (16) is made of an elastomeric material which is impermeable to the fluid introduced to inflate it, as well as to the fluid which passes through the valve. is substantially equal to the diameter of the inlet and outlet conduits when the pressure inside the bag is approximately equal to atmospheric pressure so that, when the valve (10) is in the open position, it provides a passage substantially cylindrical connecting the inlet duct to the outlet ends The ends of the pocket (16) are held between the central part (14) of the closure element and the two side rings (15), (150 by means of screws for fixing the side rings to the central part, so that when the bag (16) is inflated, the inflation fluid cannot escape from said bag. The body (11) of the valve further comprises a conduit (18) for inflating fluid passing through the body of the valve and opening into the inflatable bag (16). By introducing the pressurized fluid through this supply duct (18), the pocket (16) inflates, which reduces the cross-section of the passage of communication (130 and therefore the valve flow. The pressure regulation of the inflatable bag (16) provides a function to regulate the valve flow. To close the valve, simply rotate the ball so that that the communication passage (130 is not in contact with the inlet duct (1) or the outlet duct (2).

Figures 4 and 5 show an embodiment in which the valve (20) is provided with a rotating ball (21) mounted in the body (22). This ball (21) is hollowed out and provided with two circular openings (23a) and (23b) arranged to constitute said communication passage connecting the inlet duct (1) to the outlet duct (2). It further comprises two annular grooves (24), (24 ') produced at the ends of the communication passage. In this embodiment, the inflation pocket is in the form of a cylinder (25), made of waterproof elastomeric material, mounted in the communication passage and the ends of which are held in sealed manner by two rings (26), (26 ') respectively inserted in the annular grooves (24), (24'). The ball (21) is equipped with a handle (27) to control its rotation. In this embodiment, the supply conduit (28) for the inflation fluid is arranged along the axis of rotation of the ball (21).

In the embodiment illustrated in Figures 6 and 7, the valve (30) comprises a spherical ball (31) provided with two peripheral grooves (32), (32 '). The axis of these grooves is substantially coincident with the axis of the communication passage (33) connecting the inlet duct to the outlet duct. The inflatable pocket (34) consists of a cylinder (35) made of elastomeric material. This cylinder (35) is introduced into the passage (33) and its ends are folded outwards so that it can be introduced into the grooves (32), (320- In an alternative embodiment, the two cylindrical grooves (32 ) and (32 ') can be joined so as to form only one diametrical groove, the assembly of the cylinder of elastomeric material on the ball is however identical in both cases.

Figures 8 and 9 show an embodiment in which the spherical ball (21) of Figures 4 and 5 is replaced by a plug consisting of a cylindrical block (40) associated with two spherical caps. This embodiment has the same characteristics of operation than the previous embodiment. In particular, the supply conduit (41) for the inflation fluid is coaxial with the pivot axis of the plug (40) so that it remains substantially immobile when this plug is pivoted.

Figures 10 and 12 illustrate an embodiment in which the valve (50) comprises a spherical ball (51). This ball is entirely surrounded by an inflatable pocket (52) while providing a passage (53) between the inlet duct and the outlet duct. It is also integral with a handle (54) for controlling its rotation about an axis substantially perpendicular to the axis of the inlet and outlet conduits. An inflation fluid supply conduit (55) passes through the body of the ball (51) and opens into the passage (53) of the inflatable bag. Another supply duct (550 of the inflation fluid passes through the valve body and the elastomeric material surrounding the ball (51) and opens into the part of the inflatable bag (52) which is in contact with the valve body These two conduits are coaxial with the pivot axis of the ball. When the user wants to close the valve by turning the ball, it creates a slight depression in the part of the inflatable bag in contact with the valve body. means of the conduit (550 figure 10. This depression allows the creation of a space (56) between said valve body and the ball, which facilitates its pivoting. In the case where the pressure in the pocket is normal (figure 11 ), the space between the valve body (50) and the pocket (52) is nonexistent, which ensures that the ball (51) is held in place. When a high pressure is introduced into the inflatable pocket ( 52) by means of the conduits (55) and (550 Figure 12, the valve (50) closes and the ball (51 ) is locked in position in the body.

Figure 13 shows an embodiment of a valve (60) whose ball has a threaded bore (61) constituting a communication passage (62) between an inlet pipe (1) and an outlet pipe (2) . This bore (61) comprises, for example in the vicinity of the inlet duct, a section (63) of a diameter substantially equal to the diameter of the inlet and outlet ducts, and a section (64) of slightly larger diameter . A hollow cylindrical insert (65) is housed in said threaded bore (61). This insert has an external thread (.66) arranged to cooperate with the thread of the bore (61), and an annular stop bead (67). The length of the insert (65) is substantially equal to the length of the bore (61) and the stop bead (67) is positioned in such a way that when it bears against the small section (63) diameter of the bore (61), the ends of the insert (65) substantially match the ends of the bore (61). A seal (68) is also provided between the stop bead (67) and the section (63), so as to prevent the fluid passing through the valve, from seeping between the ball and the insert ( 65). The inner surface of this insert is covered with a cylinder (69) of waterproof elastomeric material, the ends of which are glued or crimped onto the outside diameter of the insert (65). The latter further comprises an opening (70) disposed in the extension of a supply conduit (71) for the inflation fluid, so that the cylinder (69) of elastomeric material constitutes an inflatable pocket (72) providing a function regulating valve. This embodiment has the advantage of allowing an easy change of the inflatable bag (72) if it deteriorates or if it is not suitable for the fluid passing through this valve. It also allows the disassembly of the insert itself.

The valves produced according to the present invention and comprising a ball or a rotary plug have the advantages mentioned above. The valve can be closed by rotation of the closure element without inflating the airbag, by turning it a quarter of a turn. This possibility is particularly advantageous when it is desired to clean or unblock the communication passage.

The present invention is not limited to the embodiments described above, but extends to any modification obvious to a person skilled in the art. In particular, the method of fixing the inflatable bag can be of any type, provided that it allows a waterproof fixing to be made and that it withstands the pressure in the bag when it is inflated. This method of attachment may include welding, gluing, pinching by insert or by fixing parts. The ball or the bushel can be made of any suitable material and in particular steel, a rigid plastic material or foam rubber covered with a layer of waterproof material.

In the case of a hollow ball, the inflation of the inflatable bag can be produced by other means than by the introduction of pressurized fluid. These means can be electrical, chemical, magnetic, thermal, or mechanical.

FIGS. 14 and 15 illustrate an alternative embodiment in section, of which a half-section illustrates the uninflated position of the bag while the other section illustrates the inflated position, FIG. 14 showing the valve in one of its positions, while Figure 15 shows the other of the positions. In this embodiment, elements similar to the previous embodiments have the same references. Note that the valve of course includes an inlet conduit (1) and an outlet conduit (2) as well as the closure element (13) but it comprises at least one inspection conduit (100, 200). Thus, in the embodiment given by way of example, the valve comprises two additional orifices or conduits (100, 200) whose axis is perpendicular to the axis of the inlet (1) and outlet ( 2). These additional conduits making it possible to check the state of the closure element (13) and in particular of its inflatable pocket (16) without having to dismantle the valve. Said inspection conduits (100, 200) may include closure plugs (101, 201). Furthermore, this arrangement allows the use of the valve in both directions.

Note, moreover, that the closure element (13) may in addition to the inflatable pocket (16) include other elements such as a filter (160) and / or a valve (161) as illustrated in the figure 16.

Claims

1. Ball or plug type control valve having a body defining a housing for a closure element arranged to define a communication passage between an inlet pipe and an outlet pipe when the valve is in the open position and to close this passage when the valve is in the closed position, characterized in that the closure element (13) is equipped with at least one pocket (16, 34, 52, 72) inflatable with a fluid under pressure, so as to pneumatically seal said communication passage (13 ′, 62).

2. Valve according to claim 1, characterized in that the inflatable bag (16, 34, 52, 72) is made by means of an elastomeric material airtight and fluids passing through the valve.

3. Valve according to claim 2, characterized in that the waterproof elastomeric material constituting the inflatable bag (16, 34, 52,

72) is made up of several textured layers.

4. Valve according to claim 1, characterized in that the inflatable bag (16, 34, 52, 72) is connected to a supply duct (18, 28, 41, 55, 71) of the inflation fluid passing through the shutter element.

5. Valve according to claim 1, characterized in that the inflatable bag (16, 34, 72) has an inner part of substantially cylindrical shape whose diameter is substantially equal to the diameter of said communication passage (130, and in that the ends of said pocket (16, 34, 72) are fixed to said closure element (13) on either side of this passage.

6. Valve according to claim 5, characterized in that the ends of the pocket are fixed to said closure element by means of two rings (26, 26 ') arranged on either side of said closure element.

7. Valve according to claim 5, characterized in that the ends of the pocket (16) are fixed to said closure element by means of two lateral rings (15, 150 arranged on either side of a central part ( 14), said side rings (15, 150 being fixed by means of screws to said central part (14).

8. Valve according to claim 1, characterized in that the elastomeric material completely surrounds the ball (51) or the plug, while providing a communication passage (53) between the inlet duct and the outlet duct, and in defining an inflatable pocket (52) disposed in said communication passage.

9. Valve according to claim 8, characterized in that it comprises two supply conduits (55, 550 of the inflation fluid, one of these conduits (55) passing through the ball or the plug and opening into a part of the inflatable pocket (52) located in the communication passage (53), the other conduit (550 opening into a part of the inflatable pocket (52) in contact with the valve body.

10. Valve according to claim 1, characterized in that it comprises an interior insert (65) engaged in the communication passage (62) and covered with a cylinder (69) of elastomeric material forming said inflatable pocket (72).

11. Valve according to claim 10, characterized in that said inner insert (65) comprises at least one opening (70) connected to the supply conduit (71) of the inflation fluid, arranged to allow the introduction of the fluid into said inflatable pocket (72).

12. Valve according to claim 11, characterized in that said insert comprises an external thread (66) arranged to cooperate with an internal thread (61) of the closure element (60).