CN205400663U - Packer is protected to sleeve pipe for fracturing - Google Patents

Abstract

The utility model discloses a casing protection packer for fracturing, which comprises: an upper joint, a central pipe, a back cap, a rubber sleeve ringed on the central pipe, a rubber sleeve sleeved on the central pipe and pressed against the rubber sleeve. Bowl sheath, support sleeve threadedly connected with the cup sheath, leather cup vulcanized integrally with the support sleeve, lock sleeve, piston set on the center tube, starting nail connecting the piston and lock sleeve, ring on the center tube The lock ring seat, the lock ring sleeved on the lock ring seat, the lower joint that is threadedly connected with the lower end of the central tube and is close to the lock ring seat, and the sealing element. The utility model satisfies the process requirements of volumetric fracturing in the oil field, from casing annulus to flush wells with large displacement, to inject fracturing fluid from tubing with large displacement, and to blow out; the specially designed combination of rubber cartridges can withstand high down pressure, It can well protect the upper casing; during the downhole process, it protects the rubber cup from damage; the tool relies on hydraulic setting and unsealing, and after running into the wellbore, it can be used repeatedly until the sealing cup and rubber tube are completely lost.

Description

A casing protection packer for fracturing

technical field

The utility model relates to a casing protection packer for fracturing.

Background technique

In recent years, due to the continuous development of high-efficiency oil and gas fields and the decrease of high-grade oil reservoirs, the demand for oil in various countries in the world has increased rapidly. The advantages of development can be applied in large quantities. Among them, the horizontal wells whose production cannot meet the requirements must be modified by stimulation measures. On this basis, the staged fracturing technology of double-sealed and single-slip horizontal wells is proposed. At present, when the commonly used hydraulic packers are running downhole, due to the large diameter of the cups, the cups cannot be well protected, and it is easy to cause scratches on the cups, damage the cups, and cause the packer to fail; Under the existing tool conditions, the upper casing cannot be effectively protected.

Utility model content

In view of the above deficiencies, the purpose of this utility model is to provide a casing protection packer for fracturing, which can protect the leather cup from damage and protect the upper casing from micro-deformation due to high pressure.

The technical scheme of the utility model is: a casing protection packer for fracturing, which includes an upper joint with internal thread of the built-in tubing, a central pipe whose upper end is threadedly connected with the upper joint, and a back cap whose upper end is threadedly connected with the upper joint , the rubber sleeve that rings on the central tube, the leather cup sheath that fits on the central tube and compresses the rubber sleeve, the support sleeve that is threadedly connected with the leather cup sheath, the leather cup that is vulcanized as a whole with the support sleeve, and the shrinkable leather cup The lock sleeve of the skirt, the piston sleeved on the central tube, the starting nail connecting the piston and the lock sleeve, the lock ring seat ringed on the central tube, the lock ring sleeved on the lock ring seat, the threaded connection with the lower end of the central tube and Fittingly against the lower joint of the lock ring seat, and the sealing element.

On the basis of the above-mentioned technical solutions, the following subsidiary technical solutions are further included:

The free outer diameter of the cup is more than 4mm larger than the inner diameter of the casing, and the cup is forcibly restricted in the cup sheath and the lock sleeve when the tool is assembled, and the outer diameter of the cup shrinks to 6-8mm smaller than the inner diameter of the casing, and at the same time The leather cup is located at the rear of the rubber cartridge.

The lock sleeve shrinks the skirt of the cup in its inner cavity when the tool is going downhole, and releases the cup after bearing high pressure for the first time.

The lock ring has one-way teeth, and the lock sleeve has corresponding tooth grooves, and the lock ring and the lock sleeve only move relative to each other along one direction.

There is a step on the central tube, the support sleeve is limited by the step of the central tube, the lock ring seat is positioned by the step on the central tube and the lower joint, and there are multiple bypass holes in the axial direction of the central tube.

Sealing elements are arranged between the central tube and the locking sleeve, between the central tube and the piston, and between the piston and the locking sleeve.

Due to the application of the above-mentioned technical solution, the utility model has the following advantages compared with the prior art:

1. Satisfy the technical requirements of volumetric fracturing in the oilfield, from the large displacement of the casing, to the well flushing, and from the large displacement of the tubing to inject the fracturing fluid and blowout;

2. In the process of going into the well, protect the leather cup from damage;

3. The tool can withstand high pressure difference, which can effectively protect the upper casing;

4. The tool relies on hydraulic setting and unsealing. After being lowered into the wellbore, it can be used repeatedly until the sealing cup and rubber tube are completely lost.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described:

Fig. 1 is a partial sectional view of the utility model;

Fig. 2 is a cross-sectional view of the utility model applied in the oil pipe and in the first state;

Fig. 3 is a cross-sectional view of the utility model applied in the oil pipe and in the second state;

Fig. 4 is a cross-sectional view of the utility model applied in the oil pipe and in the third state.

detailed description

Embodiment: As shown in Fig. 1-4, the utility model provides a specific embodiment of a casing protection packer for fracturing, which includes: an upper joint 1 with a built-in oil pipe internal thread, the upper end passes through the thread and the upper The central pipe 4 connected with the joint 1, the back cap 2 installed outside the central pipe 4 and connected with the upper joint 1 through threads, at least two rubber tubes 3 ringed on the central pipe 4 and close to the back cap 2, installed in the center The cup sheath 5 on the tube 4 and close to the rubber tube 3, and the cup sheath 5 are threadedly connected and the support sleeve 6 is limited by the step on the central tube 4. One end is shrunk in the inner cavity of the cup sheath 5 And at least partially against the cup 7 on the support sleeve 6, the other end of the shrink cup 7 and the lock sleeve 10 that is connected to the lower end of the piston 9 and threaded with the central pipe 4, and the starting nail that fixes the piston 9 and the lock sleeve 10 8. The lock ring seat 12, which is arranged in the inner cavity of the lock sleeve 10 and is threadedly connected with the central tube 4, and the lock ring 13 located in the inner cavity between the lock ring seat 12 and the lock sleeve 10, is threadedly connected with the central tube 4 and tightened. The lower joint 14 against the lock ring seat 12 and the sealing element 11 arranged between the two elements. Sealing elements 11 are provided between the central tube 4 and the locking sleeve 10 , between the central tube 4 and the piston 9 , and between the piston 9 and the locking sleeve 10 . At the same time, the leather cup 7 is located behind the rubber barrel 3, so the entire packer can withstand a high downward pressure difference. The lock ring 13 is provided with one-way teeth, and the lock sleeve 10 has cogs that match it. The lock ring 13 and the lock sleeve 10 can only move relative to each other in one direction, which ensures that the lock sleeve 10 cannot be reset and prevents the lock from being reset. The secondary contact between the sleeve 10 and the cup 7 hinders the flow of the annular liquid.

As shown in Figure 2, the utility model is connected in the casing pipe up and down in the oil pipe string.

As shown in Figure 3, when the pipe string is lowered into the predetermined position, the high-pressure liquid enters the push piston 9 from the bypass hole of the central pipe 4, cuts the starting nail 8, and the locking sleeve 10 goes down, and is locked by the one-way teeth of the locking ring 13. Reset, leather cup 7 releases.

As shown in Figure 4, during the fracturing operation, the high-pressure liquid acts on the bottom of the cup 7, the cup 7 expands radially and moves upward, drives the support sleeve 6 to push the cup sheath 5 upward, and compresses the rubber tube 4 axially, After radial expansion, the rubber tube 4 closely contacts the casing, and together with the cup 7, seals the annulus of the oil sleeve to realize the setting of the packer. Due to the one-way sealing feature of the cup 7 and its role in helping to seal the rubber tube 4 when bearing high pressure, this kind of sealing structure can withstand very high lower high pressure. When the high-pressure fluid is discharged and the well is flushed with reverse circulation, the unsealing of the packer can be realized.

Compared with the prior art, the utility model has the following advantages:

1. Satisfy the technical requirements of volumetric fracturing in the oilfield, from the large displacement of the casing, to the well flushing, and from the large displacement of the tubing to inject the fracturing fluid and blowout;

2. In the process of going into the well, protect the leather cup from damage.

3. The tool can withstand high pressure difference, which can effectively protect the upper casing.

4. The tool relies on hydraulic setting and unsealing. After being lowered into the wellbore, it can be used repeatedly until the sealing cup and rubber tube are completely lost.

Of course, the above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present utility model, and its purpose is to allow people familiar with this technology to understand the content of the present utility model and implement it accordingly, and cannot limit the protection scope of the present utility model with this. All equivalent transformations or modifications made according to the spirit of the main technical solutions of the utility model shall fall within the protection scope of the utility model.

Claims (6)

1. a pressure break casing protective packer, it is characterized in that comprising: the top connection of built-in oil pipe female thread, the central canal that upper end is connected with top connection screw thread, the back of the body cap that upper end is connected with top connection screw thread, ring packing element on central canal, it is enclosed within central canal and compresses the leather cup sheath of packing element, the splicing sleeve threadeded with leather cup sheath, the leather cup being integrated is vulcanized with splicing sleeve, shrink the lock tube of leather cup shirt rim, it is enclosed within the piston on central canal, the startup connecting piston and lock tube is followed closely, ring lock ring seat on central canal, it is enclosed within the lock ring on lock ring seat, threaded with central canal lower end and be close to the lower contact of lock ring seat, and potted component.

2. a kind of pressure break casing protective packer according to claim 1; it is characterized in that: the free external diameter of described leather cup is more than more than casing inner diameter 4mm; and leather cup imposes restrictions in leather cup sheath and lock tube when tool assemble; and leather cup external diameter is contracted to less than casing inner diameter 6～8mm, leather cup is positioned at the rear of packing element simultaneously.

3. a kind of pressure break casing protective packer according to claim 2, it is characterised in that: described lock tube is gone into the well in process at instrument, shrinks leather cup shirt rim intracavity within it, and is discharged by leather cup after holding high pressure first.

4. a kind of pressure break casing protective packer according to claim 3, it is characterised in that: described lock ring has unidirectional tooth, and lock tube has matched teeth groove, only along unidirectional generation relative motion between lock ring and lock tube.

5. a kind of pressure break casing protective packer according to claim 1 or 2 or 3 or 4; it is characterized in that: described central canal has step; splicing sleeve is spacing by the step of central canal, and lock ring seat is positioned by the step on central canal and lower contact, and center pipe axle upwards has multiple by-pass prot simultaneously.

6. a kind of pressure break casing protective packer according to claim 5, it is characterised in that: between described central canal and lock tube, between central canal and piston, between piston and lock tube, it is provided with potted component.