SU1672071A1 - Safety device - Google Patents

Abstract

The invention relates to a valve industry, in particular to safety devices, and can be used in various industries. The purpose of the invention is to reduce the loss of the working environment when triggered by increasing the accuracy of pressure maintenance. When the pressure in the inlet cavity 2 increases, the pressure in the sub-piston cavity 11 increases, which is connected via the throttle 13 to the inlet cavity 2 and to the drain cavity 3 through the control valve 7, which opens when the pressure in the cavity 11 is exceeded. The auxiliary spring 15 loads the washer 14 and through the pusher 16 interacts with the control valves 7, supporting the positive difference on the piston 5. 1 sludge.

Description

The invention relates to reinforcement, in particular to safety devices, and can be used in various industries.

The purpose of the invention is to reduce the loss of the working environment when triggered by increasing the accuracy of pressure maintenance.

The drawing shows a safety device, a longitudinal section.

The device comprises a housing 1 with an inlet 2 and a drain 3 cavities separated by a main valve 4 connected with a piston 5 loaded with a power spring 6. On the body there is a control valve 7 consisting of a sensitive element 8. loaded with a spring 9 and a stop valve element 10. Discharge of the working environment of the supraorbed cavity 11 in the drain

The cavity 3 is provided via the control valve 7 to the tubing 12. The cavity 11 is connected to the cavity under the sensing element 8 by an opening (not shown). The over-piston cavity 11 is connected to the inlet cavity 2 via the throttle 13. In the over piston cavity 11, a washer 14 is installed. Loaded by an auxiliary spring 15 relative to the piston 5. And a pusher 16 is placed between the washer 14 and the control valve 7.

The device works as follows.

When the inlet pressure rises above a predetermined level, the pressure rises in the above piston cavity 11 and on the sensitive element 8. Under the influence of pressure on the sensitive element 8

ABOUT

vl u about vj

the shut-off element 10 of the control valve 7 opens and the working medium is discharged from the cavity 11. The control valve 7 maintains a constant predetermined pressure in the cavity 11 above the piston 5. Increasing pressure acts on the piston 5 from below, and under the action of the difference in these pressures, the piston 5 moves, opening the main valve 4. As the inlet pressure rises, the main valve 4 and the piston 5 rise and the force 6 and the auxiliary spring 15 increase. A change in the forces of both springs could lead to an increase in pressure in the system by an amount

 (Ci + C2) H

Fl

where H is the valve stroke 4 and the piston 5;

Ci and C2 - stiffness of the springs 6 and 15, respectively;

FI - piston area 5.

But a change in the force of the spring 15 leads to a decrease in pressure in the pre-piston cavity 11 by an amount

LRT

  H

where F2 is the area of the sensitive element 8.

Therefore, subject to

Ci + C2 C2 Ff F2

The total force on the piston 5 from the greater force of the spring 6 and the lower pressure in the cavity 11 will be constant when the piston 5 is raised, which prevents the system pressure above the specified level.

Claims (1)

Claims of the Invention A safety device comprising a housing with an inlet and a drain cavity separated by a main valve, connected to a piston loaded with a power spring, the piston cavity of which is connected through an inductor to the inlet cavity and to a drain valve through a control valve, characterized in that In order to reduce the loss of the working medium when triggered, a washer loaded with an auxiliary spring relative to the piston is installed in the over-piston cavity, and a pusher is placed between the washer and the control valve. P 3 2