RU2511926C2 - High-pressure pipeline - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to a machine building hydraulic drive and may be used in mobile traction and transport vehicles, industrial, road engineering, agricultural, forestry engineering and other machines, equipped with a hydraulic drive of active and passive working elements. The pipeline comprises a power sleeve and tips that press the sleeve, at the same time the sleeve is equipped with a through shell, which forms a cavity, and tips have chambers that communicate with the cavity by circular channels under pressure.

EFFECT: increased operational reliability and durability of high pressure pipelines.

5 cl, 5 dwg

Description

The invention relates to a machine-building hydraulic actuator and can be used in mobile traction vehicles, industrial, road-building, agricultural, forestry and other machines equipped with a hydraulic actuator for active and passive working bodies.

A flexible pipeline is known (RU No. 2289057 C2, IPC F16L 11/04, F16L 9/12 of January 24, 2005), in which a metal cable is wound in two directions and divided into sections by ring stiffeners. The disadvantage of this design is the decrease in the flexibility of the pipeline.

Known high pressure sleeve with a composite braid (RU No. 2381406 C2, IPC F16L 11/02, F16L 11/04 of 03/31/2008), the inner layer of the braid of which is made of pre-stretched threads. The disadvantage of this design is fatigue failure at the boundary of their fixation.

The closest in technical essence is a high pressure sleeve (patent for utility model RU No. 86700 U1, IPC F16L 11/22 dated 05/12/2009, patent for utility model RU No. 86701 U1, IPC F16L 11/22 dated 05/12/2009), which equipped with a heat-resistant shell and rings or tape forming a gap between the heat-resistant shell and the protective coating. The disadvantage of this design is that the air gap between the heat-resistant shell and the inner rubber hose does not smooth out alternating pulsations of the hydraulic drive's working processes.

The technical result of the invention is to increase operational reliability, durability and expand the functionality of flexible high pressure pipelines.

The high pressure pipeline in the prototype contains a power sleeve and ferrules, crimping the sleeve. In relation to the prototype in the claimed invention has the following distinctive features.

In the proposed high-pressure pipeline, the sleeve is provided with a strong shell forming a cavity, and the tips have chambers communicating with the cavity by annular channels filled with gas under pressure.

This allows you to reduce the normal radial and circumferential stresses in the wall of the power sleeve and smooth out the amplitude of the pulsations of these stresses by the shock-absorbing property of the gas.

In addition, a nipple is installed on one of the lugs with a pressure reducing valve, which communicates a cavity and a chamber in the lug with a pressure line breaking through the drain line with a hydraulic tank.

The nipple with pressure reducing valve will ensure the safety of the shell, as allows reaching the maximum permissible pressure in the cavity between the shell and the power sleeve when the latter ruptures, to ensure reliable communication with the hydraulic tank through the drain line.

In the proposed high-pressure pipeline, gas pressure in the cavity and chambers is created through a discharge nipple with a check valve installed on another tip.

The nipple with a non-return valve allows filling the cavity and chambers with gas and eliminating gas leakage back.

In addition, a discharge nipple with a non-return valve and a drain nipple with a pressure reducing valve can be installed on one of the tips.

Installing both nipples on one of the lugs, as an option, allows depending on the location of the drain line to more efficiently place the pipeline and organize the discharge of the working fluid into the hydraulic tank when the power sleeve ruptures.

In the proposed high pressure pipeline, as an embodiment, the shell can be made corrugated.

This design in bending sections provides flexibility of the pipeline with the exception of fractures of the shell due to its corrugated surface.

The considered signs are sufficient to achieve the claimed technical result. The present invention solves the problem of expanding the functionality of high pressure pipelines by combining a simultaneous increase in operational reliability and durability by reducing the normal radial and circumferential stresses in the wall of the power sleeve by pressure on its outer surface of the gas in the cavity, smoothing out the amplitude of the pulsations of these stresses by the shock-absorbing property of the gas, ensuring the flexibility of the pipeline with the exception of fractures of the shell due to its corrugated surface and POSSIBILITY fracture power sleeves posts cavities and chambers via a pressure reducing valve of the drain line to the hydraulic tank to protect the system from unauthorized ejection of the working fluid.

In the proposed combination of features, a new technical property arises - the simultaneous combination of reducing normal radial and circumferential stresses in the wall of the power sleeve and smoothing the amplitude of their pulsations, providing flexibility and the possibility of a gap between the sleeve and the shell with a hydraulic tank when the sleeve is torn, which allows us to conclude that the invention is consistent criteria of novelty and inventive step.

The design of the invention is illustrated by the following drawings.

In Fig.1 shows a high pressure pipeline, General view;

figure 2 - discharge nipple in the context;

figure 3 - drain nipple in the context;

figure 4 is a cross section of a power sleeve with a shell;

figure 5 - high pressure pipeline with corrugated shell, General view.

The high pressure pipeline (Fig. 1) consists of two tips 1 with connecting nuts, a power sleeve 2, a durable shell 3, worn on the sleeve 2, crimped by the tips and forming a sealed cavity 4. In the body of the tips there are chambers 5 communicating with annular channels 6 with cavity 4. On one of the tips there is a discharge nipple 7 with a non-return valve, and on the other a drain nipple 8 with a pressure-reducing valve and a discharge nipple 7 with a non-return valve and a nipple 8, drain with a pressure reducing valve, can be installed on one of the lugs.

Pressure nipple 7 (figure 2) consists of a housing 9, a spring 10, a check valve 11 with a gasket 12.

The drain nipple 8 (Fig. 3) consists of a housing 14, a spring compression plug 15 with a drain hole, a valve spring 16, a pressure reducing valve 17 with a gasket 18. By pressing the plug 15 of the spring 16, the opening pressure of the valve 17 is initially set so that there is no rupture shell walls.

The high pressure pipeline works as follows.

In the manufacture of the pipeline, the cavity between the power sleeve and the shell is filled with gas (air) under pressure through, for example, a pressure nipple with a check valve, which is additionally sealed with a polymer composition 13 (figure 2).

When applying the working fluid along the sleeve, the wall of the sleeve (Fig. 4) will be under the internal pressure P _{1 of the} working fluid in the sleeve. As you know, normal stresses σ in the radial and circumferential directions arise along the faces of the element A with a radial coordinate ρ selected in the sleeve wall. Exceeding these stresses over permissible leads to rupture of the pipe sleeve along the longitudinal axis, since the circumferential stresses are significantly greater than the radial ones.

The external pressure of the gas P ₂ in the cavity on the outer surface of the sleeve reduces stress σ in the wall of the sleeve, and the gas shell, due to the compressibility of the gas, smoothes out the pulsation of normal stresses that occur when hydraulic flows are switched and the pulsating supply of working fluid from hydrostatic pumping units increases the operational reliability and durability of the work of the sleeve of the pipeline. In this case, the effect of smoothing out the voltage pulsations increases due to the increase in the volume of the cavity 4 (Fig. 1) by the chambers 5 and the annular channels 6 in the metal tips of the pipeline.

The corrugated surface of the shell 3 (figure 5) allows you to effectively bend the pipeline without fear of a break in its wall.

When the power sleeve ruptures, the working fluid enters the cavity of the shell and, when the pressure in the chamber 5 is reached, which does not cause breaking of the wall of the shell, the pressure reducing valve 17 (Fig. 3), overcoming the force of the spring 16, opens, and the working fluid can then flow through the hole in the plug 15 through the drain line into the hydraulic tank, which allows isolating the discharge of the working fluid into the atmosphere.

Claims (5)

1. The high pressure pipeline containing a power sleeve and tips, squeezing the sleeve, characterized in that the sleeve is equipped with a durable shell forming a cavity, and the tips have chambers communicating with the cavity by annular channels filled with gas under pressure. 2. The high-pressure pipeline according to claim 1, characterized in that a nipple is installed on one of the lugs with a pressure reducing valve, which communicates a cavity and a chamber in the lug at the tip of the nozzle along the drain line with a hydraulic tank. 3. The high pressure pipeline according to claim 1, characterized in that the gas pressure in the cavity and chambers is created through a discharge nipple with a check valve installed on another tip. 4. The high pressure pipe according to claim 1, characterized in that the discharge nipple with check valve and the discharge nipple with pressure reducing valve can be installed on one of the lugs. 5. The high pressure pipeline according to claim 1, characterized in that the shell can be made corrugated.

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