SU1580330A1 - Pressure regulator - Google Patents

Abstract

The invention relates to pneumatic automation and can be used in gas supply systems. The purpose of the invention is to reduce the size and simplify the design. The gas pressure regulator contains a crank 1 in which a first regulator is installed, the valve 5 of which is connected by a rod 6 to the first sensitive element 8, in which the second sensitive element 12 is located and which is connected in a smaller step to the force setting 10. The second sensitive element is connected It is occupied with the spring of task 15 and the second regulator. On the gas flow path, a sampling unit 7 is installed behind the first regulator, connected to the throttle channel 16 with the first 9 and second 11 cavities, between which in the channel 16 there is a throttle 17. 2 Il.

Description

The invention relates to pneumatic automation and can be used in automatic pressure control systems.

The purpose of the invention is to reduce the size and simplify the design of the controller.

FIG. 1 shows the regulator in the position corresponding to the overlap of the first regulator, general view; in fig. 2 is a plot of output pressure P out (G).

The gas pressure regulator has a housing 1 with an inlet 2 and an outlet 3 cavities, a saddle 4 with a valve 5 constituting the first regulator. The valve 5 is connected by a rod 6 forming the intake 7 with the first sensing element - a stepped piston 8 forming the first cavity 9 and connected to a smaller step with a force adjuster - an adjusting spring 10. A second cavity 11 is formed in the stepped piston 8 and the second sensing element is placed 12, associated with the second regulating member saddle 13 and the flap 14, which is integral with the stepped piston 8, and the spring 15 of the task associated with the housing 1. A channel 16 connecting together with the throttle 17 the intake 7 with the first cavity 9 is communicated from the second a cavity 11, which can be communicated with the output cavity 3 through the saddle 13. The spring 18 presses the valve 5 to the saddle 4,

The location of the second sensing element 12 and the second cavity 11 in the first sensing element, installing the second sensing element 12 between the second 11 and output 3 cavities and connecting the spring 15 of the task with the housing 1 automatically adjusts the spring 15 according to the movement of the moving system The controller, Dependence-1, makes it possible to eliminate the regulation error associated with this movement.

The preliminary deformation of the spring of a task defined by the formula

Tr-f

And i / J.Ap is compensated, starting with some gas flow, an adjustment error associated with the depressurization of the first regulator.

The restriction of the second cavity 11 by the second sensing element 12 and the communication of this cavity with the channel 16 make it possible to generate pressure before the first cavity

9 from the excess in the intake 7 to the one required in the first cavity 9.

The throttle 17 before the first cavity 9 contributes to dynamic stabilization

the pressure in the first cavity 9, and supplying the pressure to the second cavity 11 from the section of the channel 16 located before the throttles 17 ensures the operation of the second regulator with a significant flow of gas

through him. This eliminates adjustment errors associated with the sealing process, which would occur if the second cavity 11 communicates with the channel section 16 behind the throttle 17, i.e. at small

gas consumption limited by choke. The communication of the second cavity 11 with a certain portion of the channel 16, the connection of the spring 15 of the task with the housing 1 and the location of the second sensitive

element 12 in the piston 8, the accuracy of controlling the output pressure in comparison with the known regulator is practically maintained.

Exception to the second sensitive

the element, the second regulator, the spring (without the adjusting screw) and the second cavity, and transferring it with new connections to the first sensitive element, the effect of downsizing and

simplifying the design, with what is associated with simplified operation, since only one force adjuster is subject to regulation.

K1 F

- Conclusion of the ratio j /. AC 1 is as follows.

As the gas flow rate and the input pressure change, the movable regulator system moves. The forces of the elastic elements associated with it, in this case the springs, on the first and second sensing elements and on the first regulator are changed.

With a single movement, for example, in the direction of opening the first regulator, the force on the first sensing element will decrease by the absolute sum Ki of the stiffnesses of all three springs.

To compensate for the force Ki, the pressure in the first cavity should increase by L P, satisfying the equality

Ki AP-AF. (1)

where A F - area difference is greater and

smaller steps of the first sensing element.

At the same time, the additive AR is ensured by the operation of the second sensitive element while increasing the

the springs on it by the value of its stiffness K2, i.e.

Dr Ј,

where F is the effective area of the second sensing element.

Replacing the AR in expression (1), get K2 AF

Ki

or

Ki -F

 one.

K2 AF

This ratio allows the design to combine the parameters, choose the best option.

It is rational to first set the parameters F and AF and the stiffnesses of the two springs adjusting Kp and valve Kk, taking into account that K1 Kp + Kk + K2, and then determine

K2

 CR + KK

one

Formula A

Tg -F

justified

in the following way.

When a small gas outlet starts from the regulator, which was set up in the non-flow rate mode at the pressure PH (Fig. 2), the output pressure decreases. At the same time, the first sensitive element develops a force capable of depressurizing the first regulator. With some gas flow, the pressure in the intake increases, but the second sensing element, which is preloaded by the spring of the task, does not move and does not open the second regulator. The increased pressure from the intake is transferred to the first cavity. The increasing pressure, affecting the area AF, creates an additional force on the first sensing element to the adjusting spring and the output pressure, which is reduced by the value of D Pout, increases.

The transition of the curvilinear section B to rectilinear B with a certain gas flow Cmin corresponds to the complete use of the force of the pre-deformed spring of the assignment by the value A. This moment corresponds to an increase in pressure in the intake manifold and the first cavity by the value of the HELG and the total sealing force Tg, t e. when

Tr APr-AF. (2)

And n -. PodetanovIn place so DRG -

which in (2) receive

Tg

K2 A DR

or

0

five

0

five

0

five

0

five

0

five

The force Tr is calculated or taken from experimental data, taking into account the sizes of the regulatory authorities.

The regulator works as follows.

When the adjusting spring 10 is loaded in accordance with the required output pressure, the input pressure is applied to the regulator input, the shut-off element on the output line is closed, the valve 5 is pressed to the seat 4 with a sealing force and the second sensing element 12 is pressed to the valve 14 with a force springs 15 tasks, having a value of pre-deformation A.

With small gas withdrawals within Cmin (Fig. 2), the output pressure due to the redistribution of the reaction of the sealing force from the seat 4 to the sensitive element 8 is first reduced. With some gas flow, the pressure of the inhibited flow in intake 7 increases and, transferring to the first cavity 9 through channel 16 and throttle 17, has a corrective effect on the stepped piston 8. This corrective effect increases as the depressurization of the saddle 4 as the flow increases to Cmin .

At the flow rate Cmin, the valve 5 stroke is very small and the forces of the springs 10, 15 and 18 will remain almost unchanged, but the pressure in cavity 9 will increase so much that the second sensitive element 12, overcoming the pre-deformation force A of the spring 15 defined by the formula, moves away from the valve 14 and the excess gas inflow through the intake 7 is discharged into the output cavity 3. Thus, the output pressure, reduced by the value of FRt, occurs as a result of overcoming the sealing force Tg of the first regulator, at the flow rate Cmin compensates with an increase in pressure in the first cavity by the value of the HEL and the output pressure takes on the value of PH, which was established when adjusting the regulator.

With a further increase in gas flow, when the displacement of the stepped piston 8 and the deformation of the regulator springs become significant, the output pressure correction is performed by the same elements of the regulator as in the low flow mode, but using the change in the spring force 15 of the reference. So with

 one

due to the additional deformation of the latter, its force increases, the pressure in the second and first cavities, squeezing the second sensitive element 12 with the saddle 13, also increases,

When performing the ratio of parameters

Kif

the corrective action of pressure in the first cavity 9 ensures a constant output pressure of the regulator and section B of the graph (Fig. 2) will be horizontal.

The area smaller than the step of the stepped piston 8 is the effective area of the first sensing element, ensuring its response to changes in the output pressure and automatic movement of the valve 5, which changes the flow of gas into the output cavity 3.

Errors inherent in static regulators by the operation of corrective links are eliminated in the expenditure mode exceeding Cmin. and are limited (ARs) along the flow axis to a range of zero

BEFORE Smin.

The use of the proposed regulator will allow designing pressure control systems more compact with simplified technology for their maintenance.

Formula of the Invention The gas pressure regulator, comprising a housing, between the inlet and outlet cavities of which a first regulating member is installed, the valve of which is connected with the rod to the first sensitive element - a stepped piston, a smaller step connected with the force adjuster and forming

fax

0

five

five

0

with the housing, the first cavity connected with the intake channel installed in the gas flow path behind the first regulator, the second sensitive element connected with the spring of the task and the second regulator located in the second cavity and communicated with the outlet cavity, characterized in that in order to reduce overall dimensions and simplify the design, the second cavity and the second sensitive element are placed in the stepped piston, the second sensitive element is installed between the second and output cavities, the spring of the task coupled to the housing, and the second cavity is connected with the channel, wherein between the first and second cavities located choke, the following relation holds:

Ki -F

K2 AF

 one,

where Ki is the total stiffness of the movable controller system;

K2 is the spring stiffness of the task;

F is the effective area of the second sensitive element;

A F is the difference of the areas of the larger and smaller stages of the step piston, and the spring of the task in the regulator position corresponding to the overlap of the first regulator is installed with a preliminary deformation A determined by the formula

d- Tr-F

M K2 AF1

where TU is the force of sealing the first regulatory authority.

h--

Claims (1)

Claim A gas pressure regulator comprising a housing, between the inlet and outlet cavities of which a first regulatory body is installed, the valve of which is connected by a rod to the first sensing element - a step piston, a lower stage connected to the force adjuster and generating Figure 2