SU900268A2 - Pressure regulator - Google Patents

Description

one

The invention relates to pneumatic automation and can be used in gas supply systems of various technological complexes.

According to the main author. St. No. 590715, a pressure regulator is known, comprising a housing with inlet and outlet nozzles and a sensing element arranged therein, associated with a spring of a task, a rod and a regulating member made in the form of a spring-loaded hollow stepped piston, in which a seat is mounted and a valve is installed, the associated through the rod with a sensitive element 1.

However, in the known pressure regulator, each setting of the output Pressure requires its adjustment of the hollow piston spring. Changing the output pressure setting requires reconfiguration (change of compression) of the hollow piston spring. The latter is possible on a special stand or

requires for its implementation on-site installation of additional equipment. This is due to the need to change the beginning of the lowering of the hollow piston when changing the tuning pressure, which degrades the performance characteristics of the regulator, since it complicates its adjustment and is a disadvantage of the known technical solution.

The purpose of the invention is to simplify the adjustment of the pressure regulator.

This goal is achieved by the fact that the pressure regulator contains a spring, and between the steps of the hollow stepped piston an additional step is formed, which forms a cavity with the atmosphere connected to the body. in which a compression spring is installed, the cavity, formed by the end surface of the larger stage of the hollow stepped piston and the housing, communicates with the cavity of the outlet pipe.

With this design of the regulator, its hollow piston is exposed to the output pressure against the sensitive element, while the inlet pressure presses the hollow piston in the opposite direction. This provides an automatic change in the start of the lowering of the hollow piston when the set pressure is changed. For example, as the output pressure decreases, its force on the hollow piston decreases. The beginning of the lowering of the latter will occur when the input pressure decreases to a smaller value. The difference in input and output pressure, at which downward movement of the hollow piston begins, will be unchanged. The same differential is minimal, since the flow rate does not depend on the input pressure over the output pressure. Below this differential, the flow rate already depends on the magnitude of the overpressure, a further decrease in the inlet pressure causes a decrease in the gas inflow to the regulator output, where the pressure from this should decrease. However, the hollow piston under the influence of the outlet pressure drops down, increasing the flow area and compensating due to a decrease in the pressure drop at the inlet and outlet of the regulator and the decrease in reduced pressure.

Figure 1 is a schematic representation of a pressure regulator.

The pressure regulator contains a housing 1 with an inlet 2 and an outlet 3 with nozzles and located in it a sensing element connected with the spring 5 to set the compression by means of the screw p is controlled by the screw b through the plate 1, the rod. 8 and the regulator 9, made in the form of a spring-loaded hollow stepped piston) - (I 10, in which the saddle 11 is made and a valve 12 is installed with a spring 13 connected through the rod 8 to the sensitive element A.

The hollow piston 10 is made of a three-stage and facing the end surface of a smaller stage to the output cavity And the controller. The cavity 15, formed by the hollow piston 10 between its largest diameter stage and the housing, communicates on one side with the inlet duct 2, and with

the other side channels 16 with the input cavity 17 of the valve 12 and further through the gap between the valve and the seat

11 and through channel 18 with an output cavity 1 4 of the regulator. The cavity 19 between the step of the average diameter of the piston 10 and the housing 1 by the channel 20 is in communication with the atmosphere; a compression spring 21 is installed in this cavity, leading the hollow piston up (from the sensing element 4). The hollow piston 10 with an end face of greater gravity and body 1 forms a cavity 22, connected by channels 23 to the over-valve cavity and further through channel 25 in valve 12 and channel 18 in the hollow piston to the output cavity 14 of the regulator and channel of the outlet 3. The cavity 22 can be communicated with the output cavity 14,

for example, a channel in the housing. Housing

I closed by glass 2b.

The pressure regulator operates as follows.

In the initial position, the spring 5 of the task is compressed with a screw b through the plate 7, the sensitive element 4 is maximally raised. 10 piston spring 21

lift up against the stop in the housing 1. Valve 12 with the sensitive element k through the rod 8 is depressed from the seat 11. The cavity of the inlet nozzle 2 through the cavity 15, channels 16, cavity 17, the gap between the valve 12 and the saddle 11 and channel 18 communicates with the output cavity 14 regulators and further with the cavity of the outlet pipe 3.

High pressure gas is supplied to cavity 15 through inlet

2 and further along channels 16 enters the inlet cavity 17 of valve 12. In the gap between the valve 12 and the seat

The IIgas is throttled, its pressure decreases. The reduced pressure gas through the channel 18 enters the inlet cavity 14, from where it goes to the consumer via the outlet nozzle 3. At the same time, the reduced pressure gas through the channel 25 enters the over5 valve cavity 24, from where it passes through the channels 23 into the cavity 22. The gas pressure in the cavity 22 and in the cavity 14 increases. As the pressure in the exit cavity 14 increases, the sensing element 4 goes down, compressing the spring 5 of the task. When setting pressure is established in the output cavity, the sensing element 4 goes down

Claims (1)

5 So much so that the valve 12 forms with the saddle 11 a slit, the flow of gas through which from the cavity 17 will compensate for the extraction of gas through the outlet nozzle 3 into the system behind the regulator. A dynamic equilibrium is established between the movable elements of the regulator, corresponding to a certain gas flow rate. If the gas flow rate changes, a new equilibrium occurs at a different value of the throttling gap between the valve 12 and the seat 11. In the cavity 22 the same pressure is established as in the cavity 1. The piston 10 maximally lifts up, the pressure force on the hollow piston from cavities 22 with a high inlet pressure are not able to overcome the force of the spring 21 and the force of the inlet pressure from the side of the cavity 15. With such a difference between the inlet and outlet pressure, the gas flow does not depend on the differential, but depends only on the size of the flow area. When the differential drops to a critical and higher, in which the flow rate is also determined by the differential (along with the large flow area), the piston 10 begins to fall down, compressing the spring 21 and the spring 13. This increases the gap between the valve 12 and the seat 11 , the gas inflow to the regulator output increases, eliminating the decrease in the gas pressure in the output cavity I, which would have occurred with a decrease in the input pressure. Lowering the piston 10 is proportional to the decrease in inlet pressure. The difference between the inlet and outlet pressure increases to the same extent. The downward movement of the hollow piston causes (1) the increase in the flow area of the regulator required to maintain a constant output pressure. When reconfiguring the regulator to another output pressure, the inlet pressure automatically changes, at which the piston 10 starts to descend. If, for example, the regulator is reconfigured to a higher output pressure, then the piston 10 does not begin to descend at a higher input pressure. The differential pressure will be the same; it is precisely this differential that requires an increase in the flow area of the regulator above the value determined from the condition above the critical differential pressure between the outlet and the inlet pressure. As the tuning pressure decreases, the piston 10 begins to move downward, increasing the flow area, with a lower outlet pressure, but with the same differential. The differential required to operate the piston 10 is provided with the required dimensions. The piston stages and the appropriate choice of the elastic characteristic of the spring 21. The setting (retuning) of the pressure regulator is achieved by screw 6. The hollow piston is automatically activated, this piston is started up due to structural elements and does not require special adjustment, which is achieved by making the hollow piston unbalanced in terms of outlet pressure, the force of which tends to increase the flow area of the regulator. Adjustment of the regulator was noticeably simplified and became possible without special additional equipment, which markedly improved the performance characteristics of the pressure regulator. Claims of the invention Pressure regulator according to aut. St. N 590715, characterized in that, in order to simplify the adjustment of the regulator, it contains a compression spring, and between the steps of the hollow stepped piston an additional step is formed, which forms a cavity in which the compression spring is installed with the atmosphere, and the cavity is formed the end surface of the larger step of the hollow stepped piston and the housing is in communication with the outlet nozzle channel. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 590715, 1СЛ, G 05 D 16/10, 1976 (prototype).