CN110735612A - double-acting ultrahigh-pressure clamping and sealing rubber cylinder - Google Patents

Abstract

The invention relates to a double-acting ultra-high pressure sealing rubber cylinder for sealing the annular space between the pipe string in the well and the wellbore in the wellbore. Its structure includes an upper support ring, a lower support ring, an upper rubber barrel, a middle rubber barrel, a lower rubber barrel, an anti-protrusion ring, a central tube, a rubber inner tank, an incompressible fluid (silicon oil) and a grease nipple. The principle is based on Pascal's law, the pressure applied in the axial direction is transmitted to the incompressible fluid (silicon oil) through the upper and lower rubber cylinders, and then transmitted to the radial direction by the incompressible fluid (silicon oil), acting on the middle rubber cylinder. Axial pressure and radial pressure act on the rubber cylinder at the same time, and the rubber cylinder expands radially to achieve the sealing effect. This kind of double-acting ultra-high pressure sealing rubber cylinder not only has the advantages of long sealing time, large working pressure difference, and large sealing pressure, but also solves the problem of shoulder cracks and damage caused by excessive axial displacement.

Description

A double-acting ultra-high pressure sealing rubber cylinder

technical field

The invention relates to a sealing rubber cylinder for sealing the annular space between a pipe string in a well and the wellbore in a wellbore, in particular to a double-acting ultra-high pressure sealing rubber cylinder.

Background technique

The sealant cartridge is generally installed on the packer or bridge plug, and its main function is to block the well section, and then perform operations such as fracturing, acidizing, stratified water injection or oil recovery. There are two main types of sealant cylinders used in oilfield exploitation: expansion type and compression type. The principle of expansion type rubber cylinder is that hydraulic force acts on the inner cavity of the rubber cylinder to make the diameter of the rubber cylinder larger to achieve sealing, but this type of rubber cylinder has Short sealing time, small working pressure difference, small sealing pressure, etc. The principle of compression rubber cylinder is to use the properties of large displacement and large deformation after the rubber material is stressed, and the rubber cylinder is squeezed axially to make it produce Radial expansion, so as to fit the well wall to achieve the effect of sealing the well section. However, from the point of view of field application, when the working surface of this kind of rubber cylinder is completely in contact with the casing wall, the axial compression amount reaches the maximum value, which is easy to generate stress concentration on the shoulder, which leads to the damage of the rubber cylinder and the failure of the seal. In order to achieve the effect of radial expansion of the existing compression rubber cylinder, large axial compression displacement is unavoidable, and shoulder cracks and damage have also become one of the main reasons for the failure of the rubber cylinder seal.

Therefore, how to effectively improve the working performance and service life of the compressed rubber cylinder is the current technical difficulty. The present invention will be based on Pascal's law (that is, the pressure applied to the closed liquid can be transmitted in all directions by the liquid invariably) , In particular, a double-acting ultra-high pressure sealing rubber cylinder is provided to solve the problems existing in the sealing rubber cylinder in oilfield exploitation.

SUMMARY OF THE INVENTION

The purpose of the present invention is to combine the respective advantages of the expansion type rubber cylinder and the compression type rubber cylinder to provide a double-acting ultra-high pressure sealing rubber cylinder to solve the problems existing in the sealing rubber cylinder in oilfield exploitation.

In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a double-acting ultra-high pressure sealing rubber cylinder, the structure of which includes an upper support ring, a lower support ring, an upper rubber cylinder, a middle rubber cylinder, a lower rubber cylinder, and an anti-outburst ring, Center tube, rubber liner, incompressible fluid (silicone oil) and grease nipple. The inner arc surface of the upper rubber barrel is attached to the outer arc surface of the upper part of the middle rubber cylinder, and the outer arc surface of the lower part of the middle rubber cylinder is attached to the inner arc surface of the lower rubber cylinder. A sealing mechanism is formed; the force transmission mechanism is composed of a rubber liner, an incompressible fluid (silicon oil), and a grease nozzle. The force transmission mechanism is located in the closed cavity formed by the sealing mechanism and the central tube, and the incompressible fluid (silicon oil) is filled with the rubber. The inner space of the bladder; the anti-protrusion mechanism is composed of upper and lower anti-protrusion rings; the upper support ring and the anti-protrusion ring are both sleeved on the central tube, the lower end face of the upper support ring is in contact with the upper end face of the anti-protrusion ring, and the lower end face of the anti-protrusion ring Fitted with the upper end face of the upper rubber cylinder; the anti-protrusion ring and the lower support ring are sleeved on the central tube, the upper end face of the anti-protrusion ring is fitted with the lower end face of the lower rubber cylinder, and the lower end face of the anti-protrusion ring is in contact with the upper end face of the lower support ring.

A hole is punched at the top of the outer side of the rubber inner liner, the oil filling nozzle is inserted through the hole, the circular rubber pad on the top of the oil filling nozzle is pasted on the skin of the rubber inner liner, and then the rubber inner liner is inflated and vulcanized to shape.

The oil filling nozzle is provided with a vertical oil filling seam from top to bottom, a semicircular groove in the center of the top, and a circular rubber pad around the top.

The beneficial effects of the present invention are: the present invention is based on Pascal's principle, and a force transmission mechanism is arranged in the sealing mechanism, which can achieve the advantages of long sealing time, large working pressure difference, large sealing pressure, etc., and can solve the problem of excessive axial displacement. The resulting shoulder cracks and breakage problems.

Description of drawings

FIG. 1 is a schematic structural diagram of the double-acting ultra-high pressure sealing rubber cylinder of the present invention.

Figure 2 is a schematic structural diagram of the oil injection nozzle of the present invention.

In the figure: 1—upper support ring, 2—anti-protrusion ring, 3—gluing barrel, 4—grease nozzle, 5—rubber inner tank, 6—medium rubber barrel, 7—incompressible fluid (silicone oil), 8—center Tube, 9—lower rubber barrel, 10—lower support ring.

Detailed ways

In order to more clearly understand the purpose, technical solutions and beneficial effects of the present invention, the following examples are used to further illustrate, but the specific embodiments described here are only used to explain the present invention, and are not intended to limit the present invention.

Referring to FIG. 1 , according to an embodiment of the present invention, a double-acting ultra-high pressure sealing rubber cylinder includes an upper support ring 1 , a lower support ring 10 , an upper rubber cylinder 3 , a middle rubber cylinder 6 , and a lower rubber cylinder 9 , Anti-protrusion ring 2, central tube 8, rubber liner 5, incompressible fluid (silicone oil) 7 and oil nozzle 4. The inner arc surface of the upper glue cylinder 3 is attached to the upper outer arc surface of the middle glue cylinder 6, the outer arc surface of the lower part of the middle glue cylinder 6 is attached to the inner arc surface of the lower glue cylinder 9, the upper glue cylinder 3, the middle glue cylinder 6 and the lower rubber cylinder 9 together form a sealing mechanism; the force transmission mechanism is composed of a rubber liner 5, an incompressible fluid (silicon oil) 7, and a grease nozzle 4. The force transmission mechanism is located in the closed cavity formed by the sealing mechanism and the central tube 8. The incompressible fluid (silicon oil) 7 fills the inner space of the rubber liner 5; the anti-protrusion mechanism is composed of upper and lower anti-protrusion rings 2; The lower end surface of the support ring 1 is in contact with the upper end surface of the anti-protrusion ring 2, and the lower end surface of the anti-protrusion ring 2 is fitted with the upper end surface of the upper rubber barrel 3; The upper end surface is in contact with the lower end surface of the lower rubber cylinder 9 , and the lower end surface of the anti-protrusion ring 2 is in contact with the upper end surface of the lower support ring 10 .

The above-mentioned anti-outburst ring 2 is made of polytetrafluoroethylene material, and the above-mentioned upper rubber cylinder 3, middle rubber cylinder 6 and lower rubber cylinder 9 are made of nitrile rubber material. The rubber liner 5 and the oil filling nozzle 4 are made of butyl rubber, and the incompressible fluid is silicone oil.

Referring to FIG. 2 , in the double-acting ultra-high pressure sealing rubber cylinder of the present invention, the oil filling nozzle 4 is provided with a vertical oil filling seam from top to bottom, and a semicircular groove in the center of the top serves as a guide, which is convenient for the oil filling needle to be inserted into the oil filling seam. Surrounded by round rubber pads.

There is a hole on the outer top of the rubber liner 5, the oil filling nozzle 4 is inserted into the hole, the circular rubber pad on the top of the oil filling nozzle 4 is pasted on the skin of the rubber inner liner 5, and the gas needle is inserted from the oil filling nozzle 4 to the rubber inner liner 5. Put it into the vulcanizing machine to vulcanize and shape.

When injecting oil, insert the oil injection needle into the oil injection nozzle 4, first pump the rubber liner 5 to a vacuum, then inject silicone oil until it is full, continue to inject a certain amount of silicone oil to form a pre-pressure, and finally pull out the oil injection needle, the hydraulic action makes the oil injection seam closure.

When the present invention is working, an axial pressure is first applied to the present invention, and the axially applied pressure is transmitted to the incompressible fluid (silicon oil) 7 through the upper rubber barrel 3 and the lower rubber barrel 9, and then the incompressible fluid (silicon oil) 7 It is transmitted to the radial direction and acts on the middle rubber barrel 6, so that the diameter of the middle rubber barrel 6 becomes larger and fits with the casing wall. At the same time, the upper rubber barrel 3 and the lower rubber barrel 9 will also deform radially under the action of the axial force, and fit with the well wall. Therefore, as long as a certain axial load is applied, the present invention can generate a large radial expansion under the dual action of the axial force and the radial force, reduce the load on the shoulder of the rubber cylinder, improve the compressive capacity, and realize the sealing time. It has the advantages of long time, large working pressure difference and large sealing pressure.

Claims (3)

1. A double-acting ultra-high pressure sealing rubber cylinder is composed of an upper support ring (1), a lower support ring (10), an upper rubber cylinder (3), a middle rubber cylinder (6), a lower rubber cylinder (9), The anti-protrusion ring (2), the central tube (8), the rubber inner liner (5), the incompressible fluid (silicon oil) (7) and the oil filling nozzle (4) are composed, and are characterized in that: the inner arc of the gluing cylinder (3) The surface is attached to the upper outer arc surface of the middle rubber cylinder (6), the lower outer arc surface of the middle rubber cylinder (6) is attached to the inner arc surface of the lower rubber cylinder (9), and the upper rubber cylinder (3), the middle rubber The cylinder (6) and the lower rubber cylinder (9) together form a sealing mechanism; the force transmission mechanism is composed of a rubber liner (5), an incompressible fluid (silicon oil) (7), and an oil filling nozzle (4), and the force transmission mechanism is located in the sealing mechanism In the closed inner cavity formed with the central tube (8), the incompressible fluid (silicon oil) (7) fills the inner space of the rubber liner (5); the anti-protrusion mechanism is composed of upper and lower anti-protrusion rings (2). ; Both the upper support ring (1) and the anti-outburst ring (2) are sleeved on the central tube (8), the lower end face of the upper support ring (1) is in contact with the upper end face of the anti-outburst ring (2), and the lower end face of the upper support ring (2) is in contact with The end face is fitted with the upper end face of the upper rubber cylinder (3); the anti-protrusion ring (2) and the lower support ring (10) are sleeved on the central pipe (8), and the upper end face of the anti-protrusion ring (2) is connected to the lower rubber cylinder (9) The lower end surface is fitted, and the lower end surface of the anti-protrusion ring (2) is in contact with the upper end surface of the lower support ring (10). 2. A kind of double-acting ultra-high pressure sealing rubber cylinder according to claim 1, characterized in that: a hole is punched in the outer top of the rubber inner tank (5), and the oil filling nozzle (4) is inserted through the hole, and the oil filling nozzle (4) is inserted into the hole. ) on the top of the circular rubber pad is pasted on the skin of the rubber inner liner (5), and then the rubber inner liner (5) is inflated and vulcanized to shape. 3. A kind of double-acting ultra-high pressure sealing rubber cylinder according to claim 1, characterized in that: the oil filling nozzle (4) is provided with a vertical oil filling seam from top to bottom, a semicircular groove is arranged in the center of the top, and the periphery of the top is For round pads.

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