RU167372U1 - PRESSURE REGULATOR - Google Patents

Abstract

The utility model relates to mechanical engineering, namely to pneumatic automation, and can be used to reduce and control the pressure of the gas entering the consumer from the high-pressure line, for example, to regulate the pressure of natural gas at the outlet of gas distribution stations. The pressure regulator contains channels for the inlet (1) and gas outlet (22), a housing (4) with a back cover (15), inside of which a valve-stem (27) is installed with the possibility of axial movement, communicating the channels of inlet (1) and output (22) ) gas when interacting with the seat (3), the control piston (11) and the inlet pressure compensation piston (13), respectively forming the control pressure cavity (10), feedback pressure cavity (12) and the inlet pressure compensation cavity (14), at the inlet pressure compensation cavity (14) is in communication with the gas inlet channel (1), the cavity the feedback pressure (12) is in communication with the gas outlet channel (22), the control pressure cavity (10) is in communication with the gas command pressure fitting (6). The seat (3) is equipped with a profiled ring (2), and a removable union nut (8) is installed on the valve stem (27), which fixes the removable deformable seal (7). A saddle (3) with a profiled ring (2) and a union nut (8) with a seal (7) form a throttle channel with a variable area and geometry of the bore when moving the valve stem (27). Profiling the throttle channel allows you to reduce the level of noise generated in the regulator, to increase the reliability and accuracy of maintaining the outlet pressure at low gas flow rates. 5 cp f-ly; 2 ill.

Description

The utility model relates to mechanical engineering, namely to pneumatic automation, and can be used to reduce and control the pressure of the gas entering the consumer from the high-pressure line, for example, to regulate the pressure of natural gas at the outlet of gas distribution stations.

Indirect pressure regulators are known in which a shut-off valve controlled by a rubber membrane is used as an actuator (Gas equipment, devices and fittings. - M .: Nedra, 1985, p. 68). The advantage of such devices is that the actuator can be unloaded from the effects of flow and to exclude direct contact of the working medium with a rubber membrane. The disadvantage of such devices is that during operation due to mechanical and thermal influences, the rubber membrane loses its strength and dynamic characteristics, which reduces the sensitivity of the actuating element, the reliability and durability of the device.

Known pressure regulator (AS USSR No. 1171761, MKI G05 D 16/10, publ. 08/07/1985, bull. No. 29) containing a housing with inlet and outlet cavities, between which there is a regulatory body associated with a sensitive an element equipped with a control mechanism and a spring-loaded rod connected to the equalizing piston installed in the housing bore and forming a cavity with it, connected to the hydraulic damping device through the input element of the regulating organ unloading. The regulator is additionally equipped with an annular piston installed in the housing bore coaxially with the equalizing piston.

The closest in technical essence and adopted for the prototype is a gas pressure regulator (RF patent No. 2361261, IPC G05D 16/10, publ. 07/10/2009, bull. No. 19), containing gas inlet and outlet channels, a housing with a back cover, inside which is installed with the possibility of axial movement of the valve-rod, which communicates the gas inlet and outlet channels, and the control piston, which are divided among themselves to form a control pressure cavity and a feedback pressure cavity. An inlet pressure compensation cavity is formed between the piston and the rear housing cover, which is in communication with the gas inlet channel, a feedback pressure cavity is in communication with the gas outlet channel, a control pressure cavity is in communication with the gas command pressure fitting. The inlet channel is in communication with the outlet channel through a valve valve interacting with a seat located in the inlet channel. The control pressure cavity is in communication with the gas command pressure fitting by means of a damping system, which includes a separation tank with gas and hydraulic cavities and a nozzle, while the gas cavity communicates with the gas command pressure system and the hydraulic cavity through the nozzle with the control pressure cavity. In the separation vessel, the gas and hydraulic cavities are separated by means of a bellows, or a membrane box, or a flaccid membrane. The device has insufficient accuracy of maintaining the outlet pressure at low gas flow rates and a small resource due to valve wear and seat sealing, in addition, self-oscillations occur in the regulator at low flow rates, which also lead to wear of the valve-seat pair with a quick change of operating parameters, with a sudden start, a sharp increase in pressure, a sharp change in gas flow, since the regulator contains an elastic element (spring), which contributes to the occurrence of oscillatory movements of the valve relative to the seat, which leads to pressure pulsations in the outlet cavity (consumer pressure). At low flow rates, valve self-oscillations develop in such systems, which significantly reduces the reliability and accuracy of maintaining the outlet pressure.

The technical result, the achievement of which the present invention is directed, is to increase the resource of the regulator and increase the reliability of operation and the accuracy of maintaining the outlet pressure at low gas flow rates, reducing noise.

The technical result is achieved by the fact that in the pressure regulator containing gas inlet and outlet channels, a body with a back cover, inside of which a valve-rod is installed with the possibility of axial movement, communicating gas inlet and outlet channels in interaction with a seat located in the inlet channel, regulates a piston and a piston for compensating the input pressure, respectively forming a control pressure cavity, a feedback pressure cavity and an input pressure compensation cavity, wherein the input pressure compensation cavity I was connected with the gas inlet channel, the feedback pressure cavity was in communication with the gas outlet channel, the control pressure cavity was in communication with the gas command pressure fitting, the new one is that the seat is equipped with a profiled ring, and a removable union nut is installed on the valve-stem from the inlet side, which fixes a removable deformable seal located between the aforementioned flare nut and the outer surface of the valve stem, while the seat with a profiled ring and the aforementioned flare nut with deformable m seal form a throttle channel with a variable area and geometry of the bore when moving the valve-rod.

The throttle channel formed by a saddle with a profiled ring and a union nut with a deformable seal has well streamlined surfaces.

A throttle channel formed by a saddle with a profiled ring and a union nut with a deformable seal is formed by a combination of taper and cylindrical surfaces on the valve stem.

In the throttle channel formed by a saddle with a profiled ring and a union nut with a deformable seal, the outer and inner surfaces of the protrusion of the profiled ring have mating radii.

The union nut has a well streamlined surface.

On the outer surface of the seat on the side of its contact with the regulator body and between the seat and the profiled ring there are seals.

In FIG. 1 is a longitudinal section through a pressure regulator.

In FIG. 2 is a longitudinal section through a throttle assembly.

Here 1 is the gas inlet channel; 2 - profiled ring; 3 - a saddle; 4 - case; 5 - jet; 6 - fitting of command pressure; 7 - deformable seal; 8 - union nut; 9 - transmission channel of the control pressure; 10 - cavity control pressure; 11 - a regulating piston; 12 - feedback pressure cavity; 13 - piston compensation input pressure; 14 - cavity compensation input pressure; 15 - cover; 16 - spring; 17 - threaded ring; 18 - through axial channel; 19 - cuff; 20 - feedback pressure transmission channel; 21 - cuff of the valve stem; 22 - gas outlet channel; 23 - feedback fitting; 24 - filter; 25 - a sealing ring; 26 - seal; 27 - valve stem; 28 - a glass; 29 - the outer surface of the protrusion of the profiled ring; 30 - the inner surface of the protrusion of the profiled ring; 31 - cylindrical surface of the valve stem 27; 32 - conical surface of the valve stem 27; L is the thickness of the protrusion of the profiled ring; R is the radius of the mating surfaces of the protrusion of the profiled ring.

The pressure regulator contains channels for the gas inlet 1 and gas outlet 22, a housing 4 with a cover 15, inside of which a seal assembly is mounted on the valve stem 27, which is mounted for axial movement, and includes an easily replaceable deformable seal 7 fixed by a union nut 8, which communicates the inlet channels 1 and gas outlet 22 when interacting with the protrusion of the profiled ring 2 mounted on the saddle 3 in the housing 4; a control piston 11 fixed on the valve stem 27 with a threaded ring 17 to form a control pressure cavity 10 and a feedback pressure cavity 12, respectively; a piston 13 with a cup 28 to form an inlet pressure compensation cavity 14. A sealing ring 25 is installed on the outer surface of the seat 3 from the side of the housing 4, and a seal 26 is installed between the easily removable shaped ring 2 and the seat 3, which ensures the tightness of the joints and prevents gas flow between channels of inlet 1 and outlet 22 of the gas. A spring 16 is installed in the cover 15, which, acting on the control piston 11 and the valve-rod 27 rigidly connected to it, presses the deformable seal 7 fixed on the valve-valve 27 to the protrusion of the profiled ring 2 fixed in the seat 3.

A control pressure fitting 6 with a nozzle 5 and a fitting 23 with a filter 24 and a nozzle 5 are installed in the housing 4. The control pressure cavity 10 is connected via the control pressure transmission channel 9 to the nozzle 6. The feedback pressure cavity 12 is connected via the feedback pressure transmission channel 20 with nipple 23. The inlet pressure compensation cavity 14 is connected via a through axial channel 18 in the valve stem 27 to the gas inlet channel 1. Cuffs 21 are installed on the valve stem 27, and cuffs 19 are installed on the control piston 11, providing tightness of movable joints. A seat 3 with a profiled ring 2 and a valve stem 27 with a deformable seal 7 and a union nut 8 form a throttle channel with a variable flow area when moving the valve stem 27 relative to the seat 3 with a profiled ring 2. The geometry of the throttle channel is determined by the outer surface 29 and the inner the surface 30 of the protrusion of the shaped ring 2, the cylindrical 31 and the conical 32 by the surfaces of the valve stem 27, the surface of the deformable seal 7.

The pressure regulator works in conjunction with the command gas pressure system, which can be used as a pressure regulator, pressure reducer and other similar devices. These devices can use controlled gas as a working fluid. To open the regulator, the gas command pressure system is adjusted to a certain predetermined pressure, which, through the nozzle 6 and the channel 9, enters the cavity 10, as a result of which the control piston 11 moves and opens the pressure regulator through the rigidly connected valve-rod 27. Gas reduction occurs when it passes through the throttle channel with smooth, easily streamlined surfaces 29 and 30 of the profiled ring 7 and surfaces 31 and 32 of the valve stem 27. The smoothness of the throttle channel is ensured by mating surfaces with radii not exceeding R≤0.5L, where L - the thickness of the protrusion of the profiled ring. The smoothness of the surfaces of the throttle channel reduces noise during gas reduction and improves its operational characteristics.

The correction of the control pressure to select a particular mode of operation of the regulator for the output pressure, the value of which is set by the gas consumer, is as follows. With an increase in the flow rate of the consumed gas, the pressure in the gas outlet channel 22 decreases, which leads to a decrease in pressure in the feedback pressure cavity 12, which is connected through the fitting 23 to the gas outlet channel in the consumer line. Due to the decrease in pressure in the cavity 12, the control piston 11 moves and the throttle channel area increases. The control piston 11 moves until an equilibrium is established corresponding to a given output pressure at a new flow rate. With a decrease in the consumption of gas consumed, the pressure in the gas outlet channel 22 increases, which leads to a reverse movement of the control piston 11 and a decrease in the area of the throttle channel and the set gas pressure in the gas outlet channel 22 is established with a new, reduced gas flow rate.

To reduce the pressure fluctuations that occur in the gas outlet channel 22, and to ensure the stable operation of the pressure regulator, a feedback line is provided that records the pressure in the consumer pipeline into which gas flows from the outlet channel 22. Feedback is carried out by selecting pressure in the consumer channel at a distance at least 6 diameters of the pipeline after the pressure regulator and transfer of the output pressure to the cavity 12 through the feedback nipple 23. Reduction of gas pressure fluctuations, along with the use of the feedback line is provided by the nozzles 5 installed in the nozzles 6 and 23. The presence of the nozzles 5 allows to reduce the rate of increase (or decrease) in pressure in the cavities 10 and 12, which improves the dynamic characteristics of the pressure regulator and helps to increase the degree of damping of pressure fluctuations in the outlet channel gas 22 in the mode of variable loads.

To expand the controller’s functionality, ensure its stable operation at low gas flow rates, prevent stick valve 27 from sticking and reduce self-oscillations, the geometry of the throttle channel is set so that, at low flow rates and, therefore, small passage sections of the throttle channel, the valve stem 27 did not lead to a significant change in the orifice of the throttle channel. This is achieved by profiling the surfaces of the throttle channel, namely, changing the length of the cylindrical surface 31 of the valve-valve 27, changing the taper angle of the conical surface 32 of the valve-valve 27, changing the thickness of the protrusion L profiled and the possible presence of various abrasive particles in the gas, erosion of the elements of the throttle channel. Elements of the throttle channel: union nut 8, shaped ring 2, valve stem 27 are made of wear-resistant material and allow their dismantling and replacement, which increases the resource of the regulator and its reliability, as well as increase or decrease the flow control range.

The use of easily replaceable elements of the throttle channel increases the life of the pressure regulator and allows you to expand its functionality by installing elements of the throttle channel that define the "new" geometry of the throttle channel. Changing the geometry of the throttle channel is achieved by changing the angle of conicity of the conical surface 32, the length of the cylindrical surface 31 of the valve stem 27, the thickness of the protrusion L, the radius of the mating radius R of the surfaces 29 and 31 of the shaped ring 2.

The geometry of the throttle channel is ensured by the fact that

the throttle channel formed by a profiled ring 2, a valve stem 27, a union nut 8 with a deformable seal 7, has well streamlined surfaces;

outer 29 and inner 30 of the surface of the profiled ring 2, which are an element of the throttle channel, have mating radii.

elements of the surfaces of the throttle channel 31 and 32 from the side of the valve stem 27 are formed by a combination of conical and cylindrical surfaces.

the union nut 8 has a well streamlined surface.

When throttling gas, a significant pressure difference is formed between the input channel 1 and output channel 22 (including a supercritical pressure difference), oscillations are generated in the flow caused by separation phenomena and self-oscillations, while well-streamlined surfaces and profiling of the throttle channel can reduce the noise level, generated in the regulator.

Claims (6)

1. A pressure regulator containing gas inlet and outlet channels, a housing with a back cover, inside which an axial valve-stem is installed that can axially move the gas inlet and outlet channels when interacting with a seat located in the inlet channel, which regulates the piston and piston of the inlet compensation pressures forming respectively a control pressure cavity, a feedback pressure cavity and an inlet pressure compensation cavity, wherein the inlet pressure compensation cavity is in communication with the gas inlet channel, the pressure cavity The feedback loop is in communication with the gas outlet channel, the control pressure cavity is in communication with the gas command pressure fitting, characterized in that the seat is provided with a profiled ring, and a removable union nut is tightly installed on the inlet valve on the inlet side, which fixes a removable deformable seal located between the aforementioned flare nut and the outer surface of the valve stem, while the seat with a profiled ring and the aforementioned flare nut with a deformable seal form a throttle Channel variable area geometry and the flow cross section when moving the valve-stem. 2. The pressure regulator according to claim 1, characterized in that the throttle channel formed by a saddle with a profiled ring and a union nut with a deformable seal has well streamlined surfaces. 3. The pressure regulator according to claim 1, characterized in that the throttle channel formed by a saddle with a profiled ring and a union nut with a deformable seal has a cylindrical part in the initial section that passes into the expanding part. 4. The pressure regulator according to claim 1, characterized in that the throttle channel formed by a saddle with a profiled ring and a union nut with a deformable seal is formed by combined stepwise variable conical surfaces with different angles at the apex of the cones: the initial section with a small angle of taper and paired with him plot with a large angle of taper. 5. The pressure regulator according to claim 1, characterized in that the union nut has a well streamlined surface. 6. The pressure regulator according to claim 1, characterized in that there are seals on the outer surface of the seat from the side of its contact with the regulator body and between the seat and the shaped ring.