SU380906A1 - DEVICE FOR CONTROL AND PREVENT LIQUID PREVENTION - Google Patents

Description

one

The invention relates to devices for monitoring and preventing leakage of liquids.

Devices are known for monitoring and preventing external fluid leaks, consisting of a housing with two chambers, inside of which there is a double-seat valve separating each of the chambers into two cavities. The supraclavian cavity of one of the chambers is connected directly, and the sub-valve is connected via a choke with a pressure line. The subvalvular cavity of the other chamber is connected through the choke, and the valve valve is connected directly to the drain line.

The purpose of the invention is to increase the sensitivity and versatility of the device for monitoring and preventing fluid leakage.

For this, the valve chamber above the valve chamber of the device is connected by channels, containing chokes, with the valve chamber of the adjacent chamber.

The proposed device can be used anywhere on any hydraulic system that contains double-acting hydraulic cylinders.

The drawing shows a diagram of the device.

In Korggus / there is a double-seat valve, the bolt 2 of which is loaded with spring 3.

To create pressure drops when fluid flows to lines in the channels

4 and 5 chokes are installed.

To prevent sudden movements of the shutter 2, and thus to eliminate the false positives of the device during unsteady fluid flow, channels 6 and 7 also have throttles.

The device is connected to the pressure and discharge lines of the hydraulic system through channels 4 and 5, and to the connecting lines of the hydrocyliidre through channels 8 and 9.

Channels 4 and 5 through chokes, and channels

5 and 9 are directly connected to the subvalvular cavities of the .4 and B devices.

The supra valve nolost B and D of each chamber are connected by channels 6 and 7 to the subvalvate cavity of the adjacent chamber.

If the device is installed on a site containing a hydraulic cylinder with an equal volume of cavities, it can be located both before and after the device, controlled by the hydraulic system and its operation.

If the device is installed in a section containing a hydrocylander with a different volume of cavities, it is located between the hydraulic cylinder and its control device.

In the latter case, during the forward course of the hydraulic cylinder (the brush extends) the fluid

flows in the direction of the dotted arrows, and at the reverse course - the opposite.

During the direct course of the hydraulic cylinder, the device operates as follows.

The fluid entering the hydraulic cylinder creates a pressure drop at the throttle 4, a large proportion of which flows through channel 7 into the I-cavity G, and less into the cavity / 4. The areas of the cross sections of these cavities are the same, so the force 2 acts on the gate 2 from the fluid entering the hydraulic cylinder, determined by the product of the pressure differential over the area.

The fluid displaced from the hydraulic cylinder creates a pressure drop at the throttle of channel 5, a large proportion of which is created in cavity F, and a smaller pressure flows through channel 6 to cavity B. At shutter 2, the oppositely directed PI force PZ .

During the return stroke of the hydraulic cylinder, the direction of fluid flow changes. In this case, the fluid entering the hydraulic cylinder creates a pressure differential at the throttle of channel 5, a large proportion of which enters the cavity B, and the smaller - into the cavity B. At the same time, the valve has a RE force, which is displaced from the hydraulic cylinder, creates at the channel throttle 4, a pressure drop, a large proportion of which is created in cavity L, and a smaller one flows through channel 7 into cavity G. Therefore, valve R. has a force 2 acting on the gateway 2}, which is opposite to the strength of the REH, so that the valve 2 does not move when the system sealed, needed imo to the force P, and PZ when the forward stroke, and forces the RE and P during the return stroke of the hydraulic cylinder are equal in magnitude.

The equilibrium condition of the shutter can be written as follows.

(WG-PA) X () (RB - PB) X / in the direct course,

(PB -RB) XF (RA -PO X ()

during the reverse course

where P is the pressure in the corresponding chamber.

  2/2 /

It is known that the pressure drop across the dross is determined by the following equation:

AP jK.Q,

where K is a coefficient determined by the throttle geometry and fluid properties;

Q - flow through the throttle. The forces acting on the bolt 2 are in equilibrium if equality holds:

on the run

K, () K .., xF

on the reverse course

, QVo6p F K, -Q. (F-f),

where QBK is the flow rate of the fluid entering the hydraulic cylinder;

Q is the flow rate of fluid flowing from

hydraulic cylinders.

When an external or internal leakage occurs (Qiqg; the difference between the flow rates QBX and Qc appears. As a result, the force acting on the valve valve from the side of the flowing fluid becomes greater than the force from the stream. the valve begins to move. At a certain amount of leakage, the difference in forces considered becomes greater than the force of friction and friction, and the valve closes.

Subject invention

A device for monitoring and preventing leakage of fluid, consisting of a housing with two chambers, inside of which a spring-loaded gate valve is located

a valve dividing each of the chambers into two cavities, channels connecting the subvalvular cavities with the hydraulic system and the hydraulic cylinder, chokes, characterized in that, in order to increase the sensitivity and expand the field of application of the device, the valve chamber of each of the chambers is connected by channels containing chokes, with subvalvale cavity adjacent chamber.