FR2849934A1 - Fluid or gas pressure regulating valve assembly, has housing arranged between valve unit and fluid outlet on internal circuit, with APRF and/or filter device for controlling supply of gas and isolating internal circuit - Google Patents

Abstract

The assembly has a body (1) with an internal circuit (9) coupled between openings of fluid inlet (3) and fluid outlet (4) e.g. tap. A housing (8) is arranged between a valve unit and the opening of the fluid outlet on the internal circuit. The housing has an APRF (2) and/or filter device (2) for controlling a supply of gas and isolating the internal circuit. An Independent claim is also included for a method of releasing fluid.

Description

A pressure reducing valve assembly or valve is disclosed.

  intrinsic safety and / or filtration for easy maintenance and increased precision. 5 The oxygen and fuel supply circuits for tools using flames for welding, cutting, brazing, spraying, heat treatments, pickling, preheating before forging and other metalworking applications in particular, can be the seat of phenomena of passage of a gas in the circuit of the other or of "reentry of flame".

  To prevent the occurrence of these phenomena and minimize the consequences, it is common to have devices in the circuits called flame arrestor or more simply ARPF.

  These devices generally consist of an inlet connection, a body containing a non-return valve to prevent the flow of gas in the opposite direction, that is to say in the opposite direction from the desirable direction, from a porous filter called "sintered" whose role is to extinguish the combustion front of a reentry of flame, and an outlet fitting.

  The inlet and outlet connections are either intended for mounting on a conduit, or for screw connection to another component of the supply, or for snap connection in a so-called quick coupling system.

  ARPF devices are usually mounted in the torch or torch, on the line supplying the torch or torch or at the outlet of the regulator. In some cases, it is customary to mount a first ARPF device on the torch, as close as possible to the mixing point and the flame to prevent the consequences of a malfunction or improper use leading to a gas rise. in the pipe of the other or stop as soon as possible a reentry of flame, and a second ARPF device on the regulator of the bottle to prevent a possible propagation of fire occurring between the torch and the bottle.

  The ARPF device sometimes offers additional functions such as thermal flow shutdown which interrupts the passage of gas in the event of an abnormal rise in temperature, or relief valve which releases gas in the event of excess pressure. ARPF devices are described in standard NF A84 340.

  In all cases, the introduction of a safety accessory into the gas circuit requires a judicious choice and sizing, a connection therefore a good pairing of the accessory and the other components, an assembly carried out correctly, the control and maintenance of the device.

  However, when an ARPF device is attached to a pressure reducer or to a bottle pressure reducing valve, it poses a particular problem of space and weakening of the installation because it extends the outlet connection by a length, in general , of the order of 50 to 100 mm. Thus, in the event of the bottle falling or moving, this rigid appendage can transmit a large torque and break and / or cause damage to the outlet connection of the regulator, for example, which may cause leaks or difficulties in mounting or 15 disassembly detrimental to safety and the proper performance of the work.

  Furthermore, in applications which require a particularly pure gas or in which the presence of particles entails a risk, the use of a filter is often necessary. By filter is meant a device for stopping particles or removing impurities such as moisture or undesirable chemical compounds.

  Filters usually use a porous material with a porosity less than the size of the particles to be stopped or of media which coalesce, for humidity or oils in suspension, or by affinity such as activated carbon for odors, or adsorption. or by chemical reaction or by static electricity.

  When a porous medium filter is used, it introduces a pressure drop and it can be considered to create the same problems as an ARPF device.

  Generally, any safety or filtration device inserted into a gas distribution circuit induces a pressure drop. This pressure drop differs from one device to another even for devices of the same type due to the tolerances on the components and their more or less pronounced clogging which commonly results from the accumulation of dust conveyed by the gas or from charcoal following fuel backfires.

  The clogging and therefore the pressure drop induced by the ARPF device or the filter is variable over time and increases, which implies that filters and ARPF devices must be monitored and maintained. preventive and curative.

  An existing solution to limit the bulk resulting from the mounting of an ARPF device or of a filter on a bottle is their mounting on a section of hose, which limits the transmitted torque but can cause additional leaks at the interfaces between the hose and the ARPF device or filter, on the one hand, and the hose and the outlet of the regulator, on the other hand, whether the connections are ensured by clamping the hose on sockets using clamps or produced by screw connections.

  Another solution is to provide a break point between the ARPF 15 or the filter and the outlet of the regulator so that in the event of shock or excessive stress, the break occurs at a chosen point and that the most critical components , such as the high pressure connection, are not damaged. This solution leads to a leak in the event of rupture and to embrittlement of the assembly.

  Yet another solution consists in using an elbow fitting bringing the ARPF device or the filter closer to the bottle and bringing it closer to the casing thereof, which protects well against the stresses resulting from the rolling of the bottle but not against direct impact or strong tension on the hose.

  Furthermore, whether the ARPF device or the filter is mounted on the hose or on the regulator directly, the pressure drop it induces in the circuit is not known and therefore the pressure displayed on the regulator pressure gauge does not correspond at the pressure actually delivered to the powered device.

  From there, the problem which arises is to propose a regulator or valve-regulator assembly 30 making it possible to obtain a high safety of use, of reduced size, making it possible to avoid or stop the flashbacks and / or to guarantee a high purity of the gas, which does not have the drawbacks of existing devices.

  The solution of the invention consists in integrating an ARPF device and / or a filter directly into the body of the regulator or of the regulating valve, preferably in such a way that its disassembly for control, maintenance or replacement is very easy and does not require not the uncoupling of the hose leading the gas from the regulator to the circuit to be supplied with gas, and to arrange the assembly so that the ARPF type device and / or the filter is preferably located upstream of the manometer.

  Indeed, such a solution makes it possible to reduce the bulk, to allow the ARPF device to benefit from the thermal mass of the regulator; itself is cooled by the expansion of the gas, therefore increasing its efficiency, preventing the use of the regulator without ARPF device and / or without filter, guaranteeing a good dimensioning of the ARPF device and / or of the filter compared to 15 regulator flow performance since the choice is made by the manufacturer of the assembly, and to give the user control of the pressure and / or flow actually delivered by the regulator since the pressure gauge is located downstream of the ARPF or the filter. This arrangement, in addition to ensuring good repeatability of the working parameters, which constitutes a guarantee of quality, also makes it possible to detect excessive clogging of the sinter.

  In other words, the invention relates to a pressure reducing valve or pressure reducing valve assembly, in particular for pressurized gas containers, used to control the pressure and possibly the flow rate of a pressurized fluid, in particular a gas, comprising a body comprising a circuit internal connecting a fluid inlet orifice 25 to a fluid outlet orifice, characterized in that a housing is arranged on the internal circuit of the body, said housing comprising an ARPF device and / or a filter.

  Depending on the case, the assembly according to the invention may include one or more of the following technical characteristics: - the internal circuit comprises expansion means, the housing being located between said expansion means and the outlet orifice, - a high pressure manometer and a low pressure manometer connected to the internal circuit, respectively, upstream and downstream of the expansion means.

  - The low pressure manometer is fluidly connected to the internal circuit 5 at a connection site located between the housing containing the ARPF device or the filter and the outlet orifice.

  - means for controlling the fluid flow, - the expansion means and the flow control means are arranged inside the body and internal of the fluid, -. the outlet orifice is carried by an expansion of the body forming an outlet connector, the inlet orifice is carried by a portion of the body comprising fixing means, in particular a thread on its external periphery, capable of allowing fix the body on a container of pressurized fluid.

  The invention also relates to a container of pressurized fluid equipped with a regulator or valve-regulator assembly according to the invention, in particular a gas cylinder.

  According to yet another aspect, the invention also relates to a process for expanding the fluid, in which the pressure of a fluid is reduced from a high pressure (PH) to a low pressure (PB) lower than the high pressure (PH) by passing the fluid through a pressure reducer assembly to the pressure reducer according to the invention.

  The invention will be explained in more detail with reference to the appended figures.

  FIG. 1 represents a functional diagram of a gas supply installation according to the prior art, comprising a gas source 10.

  An isolation valve 11 makes it possible to send the gas to a pressure reducer in the body 1 comprising a high pressure manometer 5 giving an indication of the pressure in the gas source, an expansion valve 12, single or double 30 stage, a low pressure manometer 6 to indicate the pressure delivered at outlet 4. An ARPF device 2 or, as the case may be, a filter 2 'is inserted between outlet 4 of body 1 of the regulator and circuit 7 for using the gas. The ARPF device 2 protects the body 1 of the regulator and the gas source 10 against backfire or flame. The filter 2 'protects the operating circuit against the introduction of particles or impurities coming from the source 10, from the body 1 or from the pressure reducer or from the manipulation of the fittings.

  The regulator can be integral with the valve and the gas source. Such a device is described for example in US-A-5,975,121.

  FIG. 2 represents a regulator whose body 1 integrates an ARPF 2 device or a filter 2 ′ according to the invention and in which the low pressure manometer 6 is connected downstream of the ARPF 2 device or filter 2 ′, which allows the 10 reading of the pressure actually delivered, whatever the flow rate and the pressure drop of the ARPF 2 device or of the filter 2 ′.

  For a regulator usable in welding, it suffices to increase the body 1 of the regulator by a sufficient volume to receive the active components of the ARPF device 2 while providing a wall thickness compatible with the pressures conveyed. A housing 8 intended to receive the ARPF device 2 is machined in the body and placed in communication by holes, with the low pressure chamber, with the outlet connector 4 and the pressure gauge 6. By the set of sealing means, such as O-rings, the gas from the low pressure chamber is led into the inlet of the ARPF 2 device and the gas 20 leaving it is evacuated to the outlet connector 4 and the pressure gauge 6. Substantial gains in mass , overall dimensions and cost are possible, in particular due to the elimination of the conventional means of connection between regulator output and input of the ARPF device 2, on the one hand, and output of the ARPF device and input of the use circuit, on the other hand. The active components of ARPF (valve and sintered) are preferably the same as those used in existing ARPFs.

  Unlike non-integrated ARPFs which must be different from one gas to another and from one country to another for reasons of standards (size and direction of the threads), the integrated ARPF can be a unique model for fuel and oxygen and for all countries.

  The ARPF device 2 or the integrated filter 2 ′ are fixed in the body 1 of the regulator or of the regulating valve, for example by screwing or by interlocking with mechanical blocking.

  FIG. 3 represents the functional diagram of a pressure reducing valve with ARPF 2 integrated upstream of the pressure gauge 6, according to the invention. The isolation valve 11 is an integral part of the body 1 of the regulator.

  Preferably, the pressure reducing valve or the pressure reducing valve is designed in such a way that the installation of the housing of the ARPF or the filter does not increase the torque transmitted to the assembly in the event of an impact or a fall or traction on the 10 gas outlet circuit, and the disassembly of the ARPF or the filter is easy, quick and achievable without tools if the operator may have to carry out this intervention or with a special tool if this intervention is reserved for a specialist.

  The ARPF or the filter is preferably in the form of a monobloc cartridge with coding means preventing improper assembly, upside down for example.

  The use of a monobloc cartridge simplifies the maintenance and control of the ARPF. To check the internal tightness and the pressure drop of the ARPF, it suffices to have a control bench consisting of an instrumented adapter reproducing the housing and the fixing and sealing means of the ARPF in the body of the regulator. The control procedure is then broken down into the steps of: securing the installation comprising the ARPF to be tested, extracting the cartridge from the regulator body, 2 5 - visual examination of the cartridge (state of the sintered and seals), - introduction of the cartridge into the test and control bench, - replacement in the cartridge regulator if the control is satisfactory, or of another cartridge in good condition, - return to service of the installation .

  Another procedure can consist in having a stock of new cartridges and in systematically replacing the cartridges with new verified cartridges, which makes it possible to shorten the duration of the shutdown of the installations and to carry out the control of the cartridges in masked time, in a dedicated place, or even to subcontract this last operation. A suitable marking, can allow to know the date of commissioning of the cartridge or its expiration date.

  In the variant shown in FIG. 4, the gas is not delivered when the ARPF cartridge 18 or the filter is not in place.

  Removing the filter or ARPF interrupts the gas flow and isolates the circuit that supplies it. The ARPF is constructed in a cartridge which keeps an isolation valve 15 open in the body 1 of the regulator when it is in position. When this cartridge 18 is extracted, the valve 15 closes, which has the effect of preventing gas leaks and preventing the entry of air, humidity and dust into the regulator.

  One can also provide a feedback means which, in the event of extraction of the cartridge containing the ARPF or the filter, acts on the tap to place it in the closed position.

  Advantageously, disassembly of the filter or of the ARPF is impossible if the flow control member, such as a tap, is in a position which authorizes the flow. The realization of this last variant is facilitated if the valve is of the lever-operated type such as that described by US-A5,975,121.

  The ARPF housing can include a transparent window enabling the traces of coal resulting from the reentry of flame to be seen without dismantling.

  The pressure reducing valve or the pressure reducing valve may also incorporate a device intended to supply one or more additives to the gas supplied, such as a humidifier, a lubricator for supplying a pneumatic circuit comprising for example distributors or jacks, or a tube of permeation to odorize gas

for example.

  The invention applies to pressure reducers and pressure reducing valves intended for welding gases, high purity gases usable in the fields of health, laboratories, lasers and electronics, diving or building up 'controlled atmospheres in various fields.

Claims (10)

  1. A regulator or valve-regulator assembly used to control the pressure and optionally the flow of a pressurized fluid, in particular a gas, comprising a body (1) comprising an internal circuit (9) connecting an orifice fluid inlet (3) to a fluid outlet orifice (4), characterized in that a housing (8) is arranged on the internal circuit (9) of the body (1), said housing (8) comprising a device ARPF (2) and / or a filter (2 ').   2. Assembly according to claim 1, characterized in that the internal circuit (7) comprises expansion means (12), the housing (8) being located between said expansion means (12) and the outlet orifice (4 ).   3. Assembly according to claim I or 2, characterized in that it comprises a high pressure manometer (5) and a low pressure manometer (6) connected to the internal circuit (9), respectively, upstream and downstream of the means of trigger (12).   4. Assembly according to claims I to 3, characterized in that the low pressure manometer (6) is fluidly connected to the internal circuit (9) at a connection site located between the housing (8) containing the ARPF device (2) 20 or the filter (2 ') and the outlet (4).   5. An assembly according to claims I to 4, characterized in that it further comprises means for controlling the flow rate (11) of fluid.   6. Assembly according to claims 1 to 5, characterized in that the expansion means (12) and the flow control means (11) are arranged inside the body (1) and inside (9) of the body. fluid.   7. An assembly according to claims 1 to 6, characterized in that the outlet orifice (4) is carried by an expansion of the body forming the outlet fitting.   8. An assembly according to claims 1 to 7, characterized in that the inlet orifice (3) is carried by a portion of the body comprising fixing means, in particular a thread on its external periphery, suitable for: fix the body (1) on a container of pressurized fluid 9. A container of pressurized fluid equipped with a regulator or valve-regulator assembly according to one of claims 1 to 8, in particular a gas cylinder.   10. Method of fluid expansion, in which the pressure of a fluid is reduced from a high pressure (PH) to a low pressure (PB) lower than the high pressure (PH) by passage of the fluid in an assembly valve regulator according to one of claims 1 to 8.