WO2011089325A1

WO2011089325A1 - Valve having a sealing ring coated with a mold release agent

Info

Publication number: WO2011089325A1
Application number: PCT/FR2010/000783
Authority: WO
Inventors: Dominique Duboy; Lucien Larrieu
Original assignee: Ksb S.A.S.
Priority date: 2010-01-25
Filing date: 2010-11-25
Publication date: 2011-07-28
Also published as: FR2955639B1; EP2529135A1; FR2955639A1

Abstract

The invention relates to a valve including an annular body (1) having a groove (2) on each side surface thereof, resin (6) contacting the inner surface of the body (1), and a sealing ring (3), and having spikes (4) on the outer surface thereof and lugs (5) penetrating into the grooves (2), and a rotatably mounted throttle valve (10). The body has at least two radial through-holes (7), the inner surface of the resin (6) has notches (13), the shape of which matches that of the spikes (4), and the outer surface of the ring (3) is coated with a film (9) of a mold release agent.

Description

Sealing ring valve coated with a release agent

Butterfly valves of large diameter, of which, for example, the inner diameter is one meter and more, generally consist of an annular body lined internally with a sealing ring of elastic material, on which, at the closure the ^faucet, the disc-shaped butterfly comes to bear tightly.

To resist throttle closure stresses and strains of the conveyed fluid, ^'these sealing rings are generally provided with pins, which fit in the valve body in grooves of complementary forms.

The body of these valves being metallic, to withstand the pressure forces inside the piping, the machining is often complicated and expensive to achieve.

If these forms are simple, the attachment of the ring is random, -voire insufficient, and, if these forms are very studied, they are difficult to achieve for such large parts and editing is impossible or, at least, very difficult. (see French Patent 2,820,184).

To solve this problem, some manufacturers have invented bonding solutions or molding of polymeric material, which can releasably fix the ring in the body of the valve (see French patent FR2260041). In bonded ring solutions, the body is machined in a profile exactly corresponding to the profile of the sealing ring, while a film of adhesive ensures the adhesion of this ring to the body.

In the molded solution, complex shapes of grooves are formed in the body, while the ring ^one elastomeric seal is provided with annular lugs non-complementary shapes to those of the grooves of the body. In the free space left by these non-complementary forms, a polymer resin is deposited which, when hardening, will produce a solid locking key, which joins the sealing ring to the body. This configuration makes the sealing ring indestructible.

These solutions are technically imperfect and their disadvantages are:

- Machining gorges are technically difficult and complicated to achieve on the body of a large diameter valve, which can be one to several meters in diameter and weigh several tons.

- The filling of the grooves made in the body, during the establishment of the sealing ring, is always imperfect, because of the fluidity of the resin and the lack of release of air trapped between the body and ring.

- The sealing ring is not interchangeable. In the event of a mounting accident, or wear or damage to the ring, the valve must be removed from its piping, returned to the factory and reconditioned in the workshop, to tear and destroy the damaged ring, mechanically remove the resin polymerized in the grooves of the body, change and reassemble the new ring.

The invention overcomes these disadvantages by a butterfly valve of large diameter, for example greater than one meter in diameter, which does not require machining grooves difficult to achieve on the valve body and which can easily change the ring of sealing, when worn, to replace it with a new one, without having to return the valve at the factory. The invention relates to a valve comprising an annular body having a groove on each side face, two diametrically opposite radial shaft passages, the resin in contact and adhered with the inner face of the body, a sealing ring in contact with the inner face of the resin and having crampons on the outer face and, penetrating the grooves, tenons on the two lateral faces and a butterfly mounted rotating while coming, in a closed position of the valve, to bear against the inner face of the ring and moving away in a closed position of the valve, characterized in that the body has at least two radial through holes of smaller cross section than those of the passages, the inner face of the resin has shape grooves conjugated with that of the crampons and the outer face of the ring is coated with a release agent film.

The ring is made of an elastic material of the plastomer or elastomer type.

According to the invention, it is in the resin itself that the conjugate forms of the crampons of the ring are formed and the ring itself is coated with a coating agent. demolding, so that, after polymerization of ^'the resin, the ring can be disengaged conjugated forms spikes. To replace the ring, simply detach it from the resin. In addition, as the conjugate-shaped grooves of the resin are obtained by direct casting of the resin on the crampons, it is not necessary to provide a machining, to ensure 1 latching cleats in their conjugate forms.

The shaft passages are for the passage of the throttle valve operating shaft and., The inner shaft on which the butterfly journalled ^'.ils are circularly right section having a diameter including, for faucets large dimension, between 0.12.5 times and 0.07 times the diameter of the throttle depending on the material of the axis and the pressure to be sealed. The radial holes through the body are intended to allow the injection of resin. They are preferably also of circular cross section but may not be. Their diameter is smaller, especially equal to 1/4 of the diameter of the shaft and the lower axis. Preferably, these injection holes are arranged symmetrically with respect to the shaft passages. It is preferred to provide four diametrically opposed holes, a pair of holes being arranged symmetrically with respect to a passage. The holes remain filled with resin after it has hardened.

Preferably, the release agent for elastomer is a film, 1 to 20 microns thick, of a compound whose physicochemical properties prohibit adhesion between the elastomer and any other body. This agent consists mainly of an active component and a solvent. The active component, chosen for its anti-adhesive properties, can be, in particular:

• mica, formed of aluminum and potassium silicate,

• polytetrafluoroethylene (PTFE),

Silicone or polysiloxane, which is an organic compound formed of a silicon-oxygen chain.

The solvent may be of aqueous or hydrocarbon form. The release agent can be:

• is pasty, it is then deposited by coating with a brush or a brush,

• is liquid, it is then deposited by dipping, by coating _. by brush or brush or by mechanical or oleopneumatic spraying.

The process of depositing the release agent consists, after coating the workpiece, to wait for evaporation of the solvent. The solvent is evaporated, the room is ready for use. The ring désenclxquette all the more easily resin that a spike is mushroom-shaped having a stem from the base of the ring and a head surmounting the stem. The head protrudes laterally from the rod only on one side and, in section along a diametral plane passing through the axis of the body, the face of the projection facing the face of the ring is substantially parallel thereto. This base defines the widest part of the crampon. To ensure the possibility of disengaging, and therefore replacement of the ring, in section following a diametral plane passing through the axis of the body, the width of the projection is 1/5 to 1/3 of the width of the head and the height of the head is approximately equal to the height of the rod. Preferably, the stem has upper chamfers at an angle of 30 ° to 45 ° with the direction of the upper stem. The projections of a half ring are seen in the diametral plane passing through the axis of the body, all directed in the same direction.

Preferably, the face of the projection facing the base of the band is at a right angle of plus or minus 15 ° with the side face. the main core of the crampon or base of the ring, an angle between 105 ° and 75 °. If this condition is not respected, the crampon would become difficult to disassemble at a higher angle, less than 75 °, while in the case of a more obtuse angle, greater than 105 °, the locking function a crampon in his throat would no longer be insured and the ring could loosen under the effect of the stresses due to the speed of the fluid.

A faucet according to the invention is manufactured by obtaining a valve body according to the invention, by putting the two lateral lugs of a sealing ring into the grooves, the ring having cleats on the outer face and a layer of release agent on the outer face, by injecting resin through the holes in the space between the body and the ring, so as to fill this space and allowing the resin to harden. In the accompanying drawings, given solely by way of example:

Figure 1 is a perspective view illustrating a valve body according to the invention;

Figure 2 is a sectional view through a diametral plane passing through the axis of the valve body of a valve according to the invention;

Figure 3 is a perspective view of a portion

A sealing ring for a valve according to the invention;

Figure 4 is a sectional view on a larger scale of a stud of a ring in a valve according to the invention; and

Figure 5 is a sectional view illustrating the disassembly of a ring of a next valve

The invention.

The valve according to the invention comprises a metal annular body 1, whose inner diameter is cylindrical and the side faces equipped with grooves 2 without any other machining and a sealing ring 3, which encloses the body 1. This ring of Sealing 3 is provided on its outer surface spikes 4 spear-shaped.

The two lateral faces of this sealing ring 3 are each equipped with a lateral tenon 5, the shape of which is designed so as to ensure the seal between the flanges of the pipework and the body 1 of the tap, thanks to the complementary shapes gorges 2 of the body.

The free space between the body 1 and the ring 3 is filled by a composite material 6 consisting of a load mineral or fiber and polymer resin. This compound 6 is injected between the body 1 and the sealing ring 3 by means of four injection holes 7 made in the body 1. These injection holes are symmetrically arranged with respect to shaft passages 8, of which one is placed at the top near the maneuvering shaft and the second near the lower axis. By applying on the crampons 4, the resin forms. ^'Of the grooves 13 of shape matching that of the spikes 4.

So that the compound 6 does not adhere to the sealing ring 3, the outer face of the ring, which carries the crampons 4, is coated with a film 9 of a release agent formulated for the elastomers . A butterfly 10, bearing on the ring 3 in the closed position of the valve and at a distance from the latter in the open position, is integral in rotation with a shaft passing through one of the passages 8.

The crampons 4 of the ring 3, placed on the outer cylindrical face 11, have a harpoon or half-T mushroom shape, of which at least one face 12 of the head 17 is parallel to the cylindrical face 11 of the watertight ring. This face 12 is at a right angle of plus or minus fifteen degrees with the side face of the main stem of the crampon at an angle between 105 ° and 75 °.

As shown in FIG. 4, the value of the width L 1 of this face 12 is between 1/5 and 1/3 of the value of the width L 2 of the crampon base, in order to ensure a good engagement of the ring 3 in the composite 8, while the height H4 of this face 12 is substantially equal to half the value of the total height H3 of the crampon. The chamfers 16 and 16 ', whose angle is between 45 ° and 30 °, are defined to allow the perfect disassembly and reassembly of the crampon in its groove 13 resulting from the injection and the polymerization of the resin on the crampons 4.

According to a mode of construction shown in Figure 5, the crampons of the ring 3, that is to say their bar of the tee, can be all oriented in the same direction. By unhooking one or both tenons, you easily unclog the crampons.

According to other modes of construction, as shown in Figure 3 the tenons of a half ring are oriented in one direction and those of the other half ring in the opposite direction. Disengage the ring by unhooking symmetrically the two tenons 7 grooves 2.

Claims

1. Faucet comprising an annular body (1) having a groove (2) on each lateral face, two diametrically opposite radial shaft passages (8), resin (6) in contact and adhered with the inner face of the body ( 1) and a sealing ring (3) in contact with the inner face of the resin and having cleats (4) on the outer face and, penetrating the grooves (2), tenons (5) on both sides lateral and a butterfly (10) rotatably mounted in a closed position, bearing against the inner face of the ring (3) and moving away, in an open position,

characterized in that

The body has at least two through radial holes (7) of smaller cross-section than those of the shaft passages (8),

The inner face of the resin (6) has grooves (13) of conjugated shape with that of the crampons (4), and

The outer face of the ring (3) is coated with a film (9) of release agent.

2. Tap according to claim 1, characterized in that the spikes (4) are mushroom-shaped having a stem from the base of the ring (3) and a head (17) above the stem, the head (17). protrudes laterally from the rod only on one side and in section along a diametral plane passing through the axis of the body, the face (12) of the projection, which is turned towards the base of the ring (3), it is substantially parallel.

3. Tap according to claim 2, characterized in that, in section along a diametrical plane passing through by the axis of the body, the width of the projection represents 1/5 to 1/3 of the width of the stem.

4. Tap according to claim 2 or 3, characterized in that the height (H3 - H4) of the head

(17) is approximately equal to the height (K4) of the rod.

5. Tap according to one of claims 2 to 4, characterized in that the head (17) has chamfers (16) at an upper angle of 30 ° to 45 ° with the direction of the rod height.

6. Tap according to one of claims 2 to 5, characterized in that the crampons (4) of a half ring are oriented in the same direction.

7. A method of manufacturing a valve according to one of claims 1 to 6, characterized in that:

A valve body according to claim 7 is provided,

• the two lateral lugs of a sealing ring are placed in the grooves, the ring having cleats on the outer face and a release agent film on the outer face, · resin is injected through the holes in the space between the body and the ring, so as to fill this space, and

• the resin is allowed to cure.