FR2841958A1 - Spherical valve isolating tap is housed in tap body having inlet and outlet connections, in open position valve axial bore allows passage of fluid and in closed position communicates with leak recovery - Google Patents

Abstract

The isolating tap comprises a spherical or cylindrical valve (3) able to be oriented by a control rod and housed in the tap body (9) provided with inlet and outlet connections (E,S). In the closed position valve spherical surface forms a principal sealing system on the inlet and outlet sides. In its open position an axial bore passing through its center allows the passage of a fluid. There is also a leak recovery (5) with which the bore communicates when the valve is closed. An independent claim is included for equipment comprising at least two valves connected in series.

Description

The present invention relates to an isolation device in form

  Double or double cylindrical ball valve

and vent.

  Isolation devices with ball valves, adjustable via a drive shaft, integral with a valve operating handle, are known. The spherical ball is supported on two opposite seats carried by the connection sleeves of the valve to the inlet and outlet lines of the fluid, the angular displacement of the plug allowing alternately to close these sleeves by prohibiting the flow of fluid through the valve thus closed or, conversely, to

  communication these two sleeves through the bushel.

  An example of this kind of device is described in US-A-6220290.

  The word "spherical" refers to perfectly spherical objects but also objects with a generally spherical shape or that of a sphere

Truncated.

  A fluid wind is conventionally provided for evacuating from the isolation device the fluid that passes into the space between the bushel and the body that surrounds it. US-A-4846212 discloses an isolation device with two disks for the

  double isolation and sphere drilled rotating to form the vent.

  1 represents an isolation device section according to the prior art seen from above, FIG. 1A shows the isolation device in the open position with fluid passage from the inlet E to the outlet S. bushel 3 is a solid sphere, pierced on both sides of a bore 13 of the same diameter as the inlet and outlet connections. In the open position, the openings of the bore 13 are opposite the inlet and outlet, the space between the body 9 in which the plug is housed and the outer spherical surface of the plug is closed by toric seals 11 blocking the connection

  between the fluid passage and the space between the body 9 and the plug 3.

  In the intermediate position as illustrated in Figure 1B, the plug 3 rotates on its central axis, so that the seals 11, integral with the body 9, no longer block the fluid inlet and the fluid comes out of the collection of

fluid 5 to the atmosphere.

  In this case, a non-negligible amount of fluid is sent to the atmosphere, which poses serious problems when the fluid is flammable or toxic. In the closed position of Figure 1C, the outer surface of the plug 3 blocks the fluid inlet and outlet, and the fluid remaining in

  the bore 13 continues to flow through the collection 5.

  An object of the present invention is to reduce the amount of fluid that can pass from the inlet pipe to the outside of the isolation device when the plug changes from the "closed" position to the "open" position or the opposite. According to the invention, there is provided an isolation device in the form of a ball or cylindrical valve comprising a first spherical or cylindrical ball valve that can be rotated by a control rod and housed in the body of a valve provided with inlet connections and outlet, so that in the closed position of the first plug, the spherical or cylindrical surface of the circumference of the plug and that of the body form, on the input and output side, a main sealing system and that in position of opening of the first plug, a first axial bore passing through the center of the first plug allows the passage of a fluid through the isolation device, the plug rotating on the axis of the control rod between the open position and the closing position, and also comprising a collection of leaks characterized in that in the closed position the first bore communicates with the collection of leaks but does not communicate with the connections of entry and exit. According to other optional aspects of the invention, the device comprises the following features: - the collection of leaks is constituted by a pipe having an axis perpendicular to the direction of passage of the fluid in the inlet and outlet connections and is perpendicular is coaxial with the axis of the control rod and communicating with an opening in the body; - In the open position of the first plug, sealing means block the fluid passage between the inlet and outlet connections, the first bore and the collection of leaks and in the closed position of the first bushel block the passage of fluid between the inlet and outlet connections and the collection of leaks, while allowing the passage of fluid between the first bore and the collection of leaks; - The sealing means are constituted by a cylinder or a spherode, integral with the body, pierced with two openings to allow the passage of fluid and a third opening to allow, in the closed position, the discharge of fluid by the collection leaks; the collection of leaks communicates directly with the atmosphere and in the open position of the first bushel, the collection of leaks does not communicate with the first bore; the first plug is spherical and comprises a second ball valve which can also be turned by the control rod and connected to the first plug by a tube constituting the collection of leaks, the second plug being also housed in the valve body, so that in the open position of the first plug, the first bore communicates with the collection of leaks, which itself communicates directly or indirectly with a bore of the second plug opening on a closed space between the body and the second bushel, the second bushel in the closed position and, ii) in the closed position of the first plug, the bore of the second plug is opposite an opening in the body, so that the fluid enclosed within the first bushel passes through the collection of leaks and the bore of the second bushel to be evacuated, the second

  bushel being in the open position.

  - The closed space between the body and the second plug is sealed by a seat with a diameter equal to or greater than the diameter of the fluid outlet, radius less than that of the second plug but greater than the radius of the second bore, and possibly coaxial with the second bore; - The bore of the second plug has a length greater than or equal to the radius of the second bushel and optionally the bore of the second bushel passes through both sides of the second bushel; - In the closed position of the first plug and in the open position of the second plug, the collection of fluids communicates between the first passage and / or the space between the body and the first plug and the bore of the second plug, this bore traversing the second bushel and possibly having the same length as the diameter of the second bushel and the second bushel being fixed to the first bushel by a solid cylinder; - The collection of leaks communicates between the first bore of the first plug, a cylindrical tube connecting the two plugs and the bore of the second plug, the latter being blind and having a length less than the diameter of the second plug. (Figure 3); - The diameter of the first and second bores is chosen so that the second bushel is not yet open when the first bushel is not yet closed; - The phase angle between the axes of the first and second bores is chosen so that the second plug is not yet open when the first plug is not yet closed and preferably is equal to or greater than 90; - the vent of the second bushel is closed by at least two seals in any position relative to the outside, as long as the vent of the second

bushel is not open.

  Another object of the invention is an apparatus comprising at least two

  devices according to claims 1 to 13 connected in series.

  The advantages of such a solution are the following: - the inadvertent opening of an isolation valve when the wind is open is impossible; - the inadvertent opening of the wind valve when an isolation valve is open is impossible; - the depresurization of equipment by the wind is therefore impossible (whereas it is prohibited with a conventional system); - a single maneuver controls all the operation of the system (this maneuver can be automatic or manual); - the detection of an insulation valve leaking by the wind is always possible; the volume of gas to be evacuated is limited to the internal volume of the valve. The shutter device according to the invention will be described in more detail with references to the figures, of which: FIGS. 2A, 2B and 2C are sections of an isolation device

  according to the invention, in the open, intermediate and closed positions.

  3 represents a second isolation device according to the invention, FIG. 3A showing a section of an isolation device seen from the side, with the first open plug and the second closed plug, FIG. 3B showing a cutaway on the axis AA of FIG. 3A of an isolation device viewed from the side, with the first bushel open and the second bushel closed, - FIG. 3C showing a section on the line BB of FIG. 3A seen from above of the first plug in the open position, - Figure 3D showing a section on the line CC of Figure 3A seen from above the second plug in the closed position, - Figure 3E showing a section on the line BB seen from above of the first plug in intermediate position, - Figure 3F showing a section on the line CC of Figure 3A seen from above the second plug in the intermediate position, Figure 3G showing a section of an isolation device seen from the side, with the first bushel closed and the two XIII open cup, FIG. 3H showing a section on the AA axis of FIG. 3G of an isolation device viewed from the side, with the first plug and the second plug open, FIG. the line BB of Figure 3G top view of the first plug in the closed position, - Figure 3K showing a section on the line CC of Figure 3G view

  from above the second bushel in the open position.

  FIG. 4 shows a third isolation device according to the invention, FIG. 4A showing a section of an isolation device seen from the side, with the first open plug and the second closed plug, FIG. 4B showing a cutaway on the axis AA of FIG. 4A of an isolation device viewed from the side, with the first plug open and the second plug closed, - FIG. 4C showing a section on line BB of FIG. 4A seen from above of the first plug in the open position, - Figure 4D showing a section on the line CC of Figure 4A seen

  from above the second bushel in the closed position.

  Figures 5 to 7 are sections superimposed on lines B-B, C-C

  for different types of bushels.

  For the case of Figure 2, the seal 11 of Figure 1 are replaced by a seal 10 having a cylindrical shape if the plug 3 is cylindrical or spheroidal if the plug is spherical. The seal 10 fills the entire space between the body 9 and the plug sections 12, but is pierced with an inlet and an outlet, of the same diameter as the fluid connections or of a diameter smaller than that of the connections to allow the passage of fluid and a fluid collection outlet perpendicular to the direction of the passage of the

  fluid. The bushel has the same shape as in Figure 1.

  Thus in FIG. 2A, the fluid passes from the inlet to the outlet through the bore 13 of the plug 3, the space between the outer surface of the plug 12

  and the body being blocked by the seal 10.

  In the intermediate position (Figure 2B), the space between the plug sections 12 and the body remains blocked by the seal 10, integral with the body 9, and the plug 3 rotates so that the passage is blocked by the surface

  outer bushel 3 and sealing 10.

  Only in the closed position (Figure 2C), that is to say when the bore 13 is at least partially in front of the vent 5, the accumulated fluid

7 & I

  inside the bore 13 can flow through the gap between the two

  sections 12, the exit cut in the seal 10 and the collection of fluid 5.

  According to Figure 2, the axis of the bore 13 forms an angle of 90 between its closed position and its open position. Obviously other angles are possible. Figure 3A is a longitudinal section of an isolation device according to the invention with double bushings. The fluid inlet and outlet in the isolation device are indicated by arrows. The isolation member is constituted by two spherical plugs 3, 4 interconnected by a cylindrical tube 5. The two bushels and the tube are secured to a drive shaft 6 which is itself secured to a handful of operation 7 of the isolation device. The two bushels 3, 4 and the tube 5 are housed at

  the interior of a body 9 having the same shape as the bushels and the tube.

  The first bushel 3 constitutes an isolation valve and the second

  bushel 4 constitutes a vent valve.

  The first plug 3 is a solid sphere traversed on either side of a first bore 13 of the same diameter as the fluid inlet and outlet pipes. The first bore is permanently connected to the cylindrical tube by means of a first passage 15 starting from the center of the sphere and having the same axis as the axis of rotation of the first plug 3. The cylindrical tube 5 and

  the second passage 15 have the same internal diameter.

  The top of the first plug 3 and the underside of the second plug 4 have a cylindrical projection 8 which fits a cylindrical opening in

  the body 9 and which keeps the double bushel on its axis of rotation.

  The space between the spherical wall of the body 9 and the first plug 3 is sealed by two O-rings 11, one at the fluid inlet and one at the

level of the fluid outlet.

  The second plug 4 is also kept inside the body 9 by an O-ring seat 17, of larger diameter than those of the first plug 3. A second passage 19 permanently connects the cylindrical tube 5 with the center of the second plug 4. A second bore 21 connects the center of the second plug with the surface of the plug, parallel to the first bore, starting towards the fluid outlet and perpendicular to the axis of rotation. This second bore has a diameter slightly larger than that of the second and first passages but smaller than that of the first bore. The second bore 21 also extends parallel to the direction of passage of the fluid but towards the fluid inlet, without reaching the surface. According to FIG. 3, the axis of the second bore 21 forms an angle of 900

  with the axis of the first bore 13. Obviously other angles are possible.

  Note that the first bushel 3 of the figures has the same diameter as the second bushel 4. In reality, for the case of all Figures 3 and 4, the

  first bushel 3 will be larger in diameter than the second bushel 4.

  In the open position of the first plug 3, most of the fluid passes through the plug through the first bore. However, a small part of the fluid enters the first passage, then into the tube 5, into the second passage, the second bore and can fill the space 23 formed by the seat, the surface of the second bushel 4 and the body 9. second bushel 4 is therefore in the closed position because no fluid can come out. In order to prevent the passage of fluid in the first bore 13 to put the first plug 3 in the closed position, through the crank 7, the two plugs 3, 4 and the cylindrical tube 5 connecting them are rotated. an intermediate position and then in a closed position to

900 from the open position.

  By turning the double plug 3, 4, the first bore 13 is no longer directly in front of the fluid inlet being 5-150 of the gas flow direction, so that briefly the fluid can pass from the inlet in the bore and in the space between the body 9 and the first plug 3, without counting of course the fluid remaining inside the first bore. These leak fluids pass into the collection of leaks formed by the tube 5 and the first and second passages 15, 19 and are then released to the atmosphere by the second bore 21 which faces an opening 25 in the body. 9, closed by

  an O-ring seat 27 of the same diameter as the opening 25.

  In this way the second bushel is in the open position

  while the first bushel is in the closed position.

  FIG. 4 also illustrates an isolation device according to the invention but in which the collection of leaks is done, not through the element connecting the two bushels but through a pipe 31 attached to both the space between the first bushel and the body surrounding it and to the space between the second

bushel and the body surrounding it.

  In the open position of the first plug (Figures 4A-4D), all the fluid passes through the bore 13 of the first plug 3. By moving from the position of Figure 4A to the intermediate position, a portion of the fluid enters the space between the body 9 and the first plug 3 and from there, arrives in the pipe 31 which opens to the lower part of the body surrounding the plug 3. The fluid remains in the pipe until the first bushel 3 arrives in its closing position and therefore the second plug 4 arrives in its open position, so that the second bore 21 is opposite the entry point of the pipe 31. At this point, the fluid passes through the second bore 21 and out of the plug through the opening 25. The space between the body 9 and the second plug is isolated by means of two toric seals, the 27 isolates the opening 25 and the 29 insulating the inlet of the outer pipe 31. The seal 27 has the same diameter that the opening 25

  and the seal 29 has the same diameter as the inlet of the pipe 31.

  In this way the element connecting the two bushels 3, 4 is solid and does not

  does not allow the passage of fluid from one bushel to another.

  It will be understood that the axes of the fluid passage bore of the

  bushel and the passage connected to the vent are not necessarily perpendicular.

  In the open position of the first plug 3, a portion of the fluid accumulates in the passage 15, the tube 5 and the pipe 31 but can not penetrate into the second plug because the inlet of the second bore 21 is

  blocked by the outer surface of the second bushel 4.

  The spaces between the body 9 and the first and second bushels are

  isolated by means of two toric sealings 33, 35 placed around the tube 5.

  In the open position of the second plug (corresponding to the closed position of the first plug), the second bore 21 is opposite the inlet of the pipe 31 so that the fluid can flow to

through the second bore 21.

  FIG. 5 shows how to calculate the angle (p as a function of the radius of the plugs 3, 4 and the diameter of the bores, for the particular case in which the plugs 3, 4 have the same radius R and the bores 13, 21 the same diameter D and each bore has a length L.

1 D L2__2 (2) 8 R D)

2 2

L 1

L - = - 4R + 2RD - 4D 2 2

D tan (0) = 2 = D D

2 LL L / 4R + 2RD-4D

  E) = 2 tan-'0 D 2ta / 4R + 2RD-4D) Figure 6 shows how to calculate the angle (p as a function of the radius of the bushings 3, 4 and the diameter of the bores, for the particular case in which the Bushings 3, 4 have the same radius R and the second bores 21 have a diameter d less than the diameter D of the first bore 13 and each bore has a length L. id L2 R 1 (R-d) + 2 2 8 R 1 Jd - = - / 4R + 2Rd - 4d 2 2 d tan (2) LL 4R + 2Rd4d & '= 2 tan' dz taL 4R + 2Rd- 4d) phase shift angle> E 'for d <D Figure 7 shows how to calculate the angle ( p depending on the radius of the bushings 3, 4 and the diameter of the bores, for the particular case in which the first plug 3 has a radius R greater than r of the second plug 4 and the second bore 21 has a diameter d less than the diameter D of the first

  bore 13 and each bore has a length 1.

  i (d 12 2 2 8 -dij r 1 (rd) (+ i 14r + 2rd - 4d 2 2 d tan (21 1) = = 4r + 21d-4d 0 "= 2 tan-d = tn144r + 2rd-4cj phase shift angle> max (E; 6 ") for d <D and r <R calculation of 0 according to 1st calculation

Claims (14)

  1. Isolation device in the form of a ball or cylindrical valve comprising a first spherical or cylindrical ball (3) rotatable by a control rod (6) and housed in the body (9) of a valve provided with couplings inlet and outlet (E, S), so that in the closed position of the first plug, the spherical or cylindrical surface of the circumference of the plug and that of the body form, on the inlet and outlet side, a main sealing system and in the open position of the first plug, a first axial bore passing through the center of the first plug allows the passage of a fluid through the isolation device, the plug rotating on the axis of the control rod between the open position and the closed position, and also comprising a collection of leaks (5) characterized in that in the closed position the first bore communicates with the collection of leaks but does not communicate with the inlet fittings and Release.   2. Device according to claim 1 wherein the collection of leaks is constituted by a pipe (5) having an axis perpendicular to the direction of passage of the fluid in the inlet and outlet connections and is perpendicular or coaxial with the axis of the control rod and communicating with a opening in the body.   3. Device according to one of claims 1 or 2 wherein in position   opening of the first plug, sealing means block the passage of fluid between the inlet and outlet connections, the first bore and the collection of leaks and in the closed position of the first plug block the passage of fluid between the inlet and outlet fittings and the collection of leaks, while   allowing the passage of fluid between the first bore and the collection of leaks.   4. Device according to claim 3 wherein the sealing means are constituted by a cylinder or spherode, integral with the body, pierced with two openings to allow the passage of fluid and a third opening to allow, in the closed position, the evacuation of fluid by the collection of leaks (5). (Figure 2).   5. Device according to one of the preceding claims wherein the   collection of leaks communicates directly with the atmosphere and in the open position of the first bushel, the collection of leaks does not communicate with the first bore (Figure 2).   6. Device according to one of claims 1 to 4 wherein the first   bushel is spherical and comprising a second spherical plug (4) also adjustable by the control rod and connected to the first plug by a tube (5) constituting the collection of leaks, the second plug being also housed in the valve body, so iii) in the open position of the first plug, the first bore communicates with the collection of leaks, which itself communicates directly or indirectly with a bore of the second plug opening on a closed space between the body and the second bushel, the second plug being in the closed position and, iv) in the closed position of the first plug, the bore of the second plug is opposite an opening in the body, so that the fluid enclosed in the inside the first bushel passes through the collection of leaks and the bore of the second bushel to be evacuated, the second   bushel being in the open position.   7. Device according to claim 6 wherein the closed space between the body and the second plug is sealed by a seat with a diameter equal to or greater than the diameter of the fluid outlet, radius less than that of the second bushel. but greater than the radius of the second bore, and   possibly coaxial with the second bore.   8. Device according to claim 6 or 7 wherein the bore of the second plug has a length greater than or equal to the radius of the second plug and optionally the bore of the second bushel passes through and   other the second bushel (Figure 4 in option).   9. Device according to one of claims 6 to 8 wherein in position   for closing the first plug and in the open position of the second plug, the collection of fluids communicates between the first passage and / or the space between the body and the first plug (3) and the bore of the second plug, this bore crossing the second bushel and possibly having the same length as the diameter of the second bushel and the second   bushel being fixed to the first bushel by a solid cylinder (Figure 4).   10. Device according to one of claims 6 to 8 wherein the collection   of leaks communicates between the first bore of the first bushel, a cylindrical tube connecting the two bushels and the bore of the second bushel, the latter being blind and having a length less than the diameter of the second bushel (Figure 3).   11. Device according to one of claims 6 to 10 wherein the   diameter of the first and second bores is chosen so that the second bushel is not yet open when the first bushel is not yet closed.   12. Device according to one of claims 6 to 11 wherein the angle of   phase shift between the axes of the first and second bores is chosen so that the second bushel is not yet open when the first bushel   is not yet closed and preferably is equal to or greater than 90.   13. Device according to one of claims 6 to 12 wherein the vent of the   second bushel is closed by at least two seals in any position relative to the outside, as long as the vent of the second bushel is not open   (Figure 3, 17, 27, Figure 4, 27, 29).   14. Apparatus comprising at least two devices according to   Claims 1 to 13 connected in series.