Regulator for corrosive gas tapping in under-atmospheric conditions
The invention relates to a device for regulating a pressurized gas, said device including: a stopper ( 4 ) engaging with a seat ( 5 ) and capable of closing a pressurized gas passage; a so-called low-pressure chamber ( 29 ) downstream from the seat ( 5 ), the low-pressure chamber including a plate ( 27 ) to which the stopper ( 4 ) is coupled, and the plate being subjected to the force of a spring ( 30 ) housed in said chamber ( 29 ) and arranged concentrically relative to the seat ( 5 ) and the fastening means ( 28 ) thereof. The chamber ( 29 ) is defined by a diaphragm ( 26 ) in free contact with the plate ( 27 ). The opposite surface of the diaphragm ( 26 ) is subjected to the force of a spring ( 20 ) having a prestress which is adjustable via control means ( 13, 14 ). The control means are indexed according to two positions: a first prestress release position for ensuring the closure of the device at the stopper ( 4 ), and a second calibrated prestress position of the diaphragm ( 26 ) corresponding to the regulator operational position. A sealed chamber ( 24 ) defined by the surface of the membrane ( 26 ) opposite the low-pressure chamber ( 29 ) is formed by the prestress control means for ensuring the connection to a detector for detecting the presence of a leak or of the used gas in order to detect a potential leak at the diaphragm.
1. Device for regulating pressurized gas comprising
a body with a passage adapted to be connected to a pressurized gas;
a stopper, movable in translation along an axis and adapted to cooperate in a leakproof manner with a seat provided in the passage; a movement of the stopper in the flow direction of the fluid corresponding to a movement for closing the passage; the stopper comprising an elongated threaded portion extending downstream of the seat;
a plate comprising a threaded through hole which the threaded portion of the stopper engages;
a blocking counter-screw in the threaded through-hole of the plate;
first elastic means exerting a force on the plate and the stopper in the direction for closing the passage;
a low-pressure chamber downstream of the seat and of the stopper, the low-pressure chamber being defined by a cavity formed in the body and by a membrane fixed to the body and freely contacting the plate, the membrane being able to move as a function of the pressure in said chamber and to control the stopper, thus making it possible to regulate in said chamber the flow rate and/or pressure of the pressurized gas; the first elastic means being housed in the low-pressure chamber;
wherein the first elastic means is supported at a bottom surface of the cavity of the body defining the low-pressure chamber; and
wherein the bottom surface of the cavity of the body defining the low-pressure chamber surrounds the seat and is at a level of the seat or at a lower level that is upstream of the seat; and
wherein the bottom surface of the cavity of the body defining the low-pressure chamber forms a circular recess housing the first elastic means.
2. Device according to claim 1 , characterized in that the first elastic means comprise a first spring at least partially surrounding the stopper.
3. Device according to claim 2 , characterized in that the first spring is arranged concentrically with respect to the axis of the stopper, supported on a lower portion of said chamber along the axis of the stopper, said lower portion being at the level of the seat or at a lower level that is upstream of the seat.
4. Device according to claim 1 , characterized in that it comprises second elastic means acting on the surface of the membrane opposite the plate.
5. Device according to claim 4 , characterized in that it comprises means for adjusting the force exerted by the second elastic means.
6. Device according to claim 5 , characterized in that the adjustment means are indexed with an index corresponding to a pre-stress of the second elastic means in a working position of the regulation device.
7. Device according to claim 6 , characterized in that the adjustment means are such that they make it possible to decrease the pre-stress of the second elastic means so as to close the device.
8. Device according to claim 5 , characterized in that the adjustment means are indexed with an index corresponding to a position for closing the device whereby the force exerted by the second elastic means is released.
9. Device according to claim 1 , characterized in that it comprises a second spring whose one end acts on the surface of the membrane opposite the plate and whose other end is supported on an adjustable abutment, the abutment being adjustable in displacement along the axis of the stopper.
10. Device according to claim 9 , characterized in that it comprises a control wheel controlling the adjustable abutment and having a working position of the regulation device that is indexed by means of a mechanical indexation system.
11. Device according to claim 10 , characterized in that the indexation system comprises a position for closing the device whereby the force exerted by the second elastic means is released.
12. Device according to claim 10 , characterized in that the mechanical indexation system comprises a push button housed under an essentially cylindrical portion of the control wheel and adapted to cooperate with at least one orifice of said essentially cylindrical portion of the control wheel.
13. Device according to claim 1 , characterized in that the cavity of the body defining the low-pressure chamber comprises a raised central portion extending from the bottom of said cavity, said raised central portion housing the stopper and the seat.
14. Device according to claim 13 , characterized in that the raised central portion comprises a collar retaining the seat in the central portion, the elongated threaded portion of stopper extending through a passage in the cap.