CN107130945A - A kind of rupture disk perforated casing box cupling device - Google Patents

Abstract

A rupture disk perforating casing coupling device, which belongs to the field of oil and gas field development tools, includes a coupling body, on which protrusions extending in the axial direction are arranged at intervals along the circumferential direction, and each protrusion is provided with several There are two openings along the radial direction, each opening is provided with a nut, a rupture disk is provided between one end of the nut and the bottom surface of the opening, and a pressure cap is installed on the other end of the nut, the pressure cap is connected with the nut and the rupture disk. A cavity with a certain air pressure is formed, and a layer of self-dissolving softening film is coated on the upper end of the pressure cap; the device of the present invention is used for perforation and fracturing without destroying the structural force of the connected casing, and does not require special perforation tools and construction It can reduce the difficulty of perforating horizontal wells, and can control perforation at any time, which provides a convenient operation method for testing and controlling mining, and at the same time greatly reduces construction costs and shortens the construction period.

Description

A rupture disk perforating casing coupling device

technical field

The invention belongs to the field of oil and gas field development tools, and in particular relates to a rupture disk perforating casing coupling device.

Background technique

Fracturing is one of the main production stimulation measures in the exploration and development of oil and gas fields, and perforation is an important link before fracturing. At present, there are two types of perforation operations: conventional perforation and hydraulic sandblasting perforation. The conventional perforating operation is to lower the perforating gun into the predetermined layer of the wellbore and then blast the hole, so that the formation fluid enters the wellbore. The construction cost and risk of this operation method are high, and professional construction teams, perforating guns and Hole bombs require professional storage, transportation and maintenance. After perforating, the casing is easy to expand in diameter and casing strength is reduced. After controlling the number of holes and perforating, the effect of flow-limited cluster fracturing is not good, and it also has a great impact on oil and gas layers. ;Hydraulic sandblasting perforation mainly uses high-jet nozzles to spray holes in the target layer to allow formation fluid to enter the wellbore. This operation is much less harmful to the reservoir. However, it still needs to be lowered into special tools first. After the perforation is completed, it is taken out from the downhole, the construction process is complicated, and the cost is high. Not only that, but the number of horizontal wells has increased rapidly in recent years, and it is also difficult to operate in horizontal wells with the current perforation method.

Contents of the invention

In view of the deficiencies in the prior art, the purpose of the present invention is to propose a rupture disk perforating casing collar device, which does not require special perforating tools to be lowered, does not damage the strength of the casing body, reduces construction costs, and shortens the construction period , and can reduce the difficulty of horizontal well perforation operations.

In order to achieve the above object, the technical scheme that the present invention takes is:

A rupture disk perforating casing coupling device, including a coupling body, on which protrusions extending in the axial direction are arranged at intervals in the circumferential direction, and each protrusion is provided with several protrusions in the radial direction. There is a nut inside each opening, a rupture disk is installed between one end of the nut and the bottom surface of the opening, and a pressure cap is installed on the other end of the nut, the pressure cap forms a certain air pressure with the nut and the rupture disk. The cavity body is coated with a self-dissolving softening film on the upper end of the pressure cap.

Further, the intervals between the adjacent protrusions are 90°.

Further, the number of openings on each protrusion is 3-4.

Further, the air pressure in the cavity is standard atmospheric pressure.

Compared with prior art, the beneficial effect of the present invention is:

The device of the present invention is lowered into the bottom of the well together with the connected casing and completes the cementing operation without lifting it out. During the perforating operation, it is only necessary to use high-pressure fluid to pierce the opening and then shoot out the hole. Therefore, using this technology for perforating When drilling, there is no need to run in a special perforation tool, which can save a trip time and shorten the operation cycle; for horizontal well perforation operations, traditional perforation tools are often not centered, which not only increases the difficulty of the operation, It will also affect the perforation quality, but this device is directly attached to the well wall, so there is no problem of misalignment, and the process is simple, thus reducing the difficulty of perforating horizontal wells; The perforation operation of one interval is completed, and the present invention can run multiple devices in one trip, so as to realize the perforation operation of multiple intervals in one trip, and the efficiency is significantly improved; in addition, The perforation operation is only carried out at the opening described in the device, without destroying the structural force and strength of the connected casing.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the present invention;

Fig. 2 is a schematic cross-sectional view of the present invention;

Figure 3 is a schematic diagram of the connection of the components in the opening;

Figure 4 is a schematic diagram of the connection between the device and the sleeve.

In the figure: 1. Coupling body, 2. Nut, 3. Rupture disc, 4. Pressure cap, 5. Self-dissolving softening film, 6. Protrusion, 7. Opening, 8. Sleeve.

detailed description

The structural principle of the present invention will be discussed in detail below in conjunction with the accompanying drawings.

As shown in Fig. 1 and Fig. 2, a rupture disk perforating casing coupling device includes a coupling body 1, on which a protrusion extending in the axial direction is arranged at intervals of 90° in the circumferential direction 6. Three openings 7 along the radial direction are opened on each protrusion 6, and a nut 2 is arranged inside each opening 7, and a rupture disk 3 is installed between one end of the nut 2 and the bottom surface of the opening 7, and the The other end of the nut 2 is provided with a pressure cap 4, the pressure cap 4 together with the nut 2 and the rupture disk 3 forms a cavity with standard atmospheric pressure (see Figure 3), and a layer of self-protection coating is applied on the upper end of the pressure cap 4. Dissolved softening film5.

Working principle of the present invention:

Before operation, when the pressure cap 4 is installed, the pressure of the cavity formed by the pressure cap 4, the nut 2 and the rupture disk 3 is at standard atmospheric pressure, so that the start-up pressure of the rupture disk 3 can be precisely controlled without comprehensive consideration of the formation pressure , and the self-dissolving softening film 5 applied on the upper end of the pressure cap 4 will isolate the components in the opening 7 from the cement, and use its own dissolvability to completely ablate within a period of time, so as to prevent cementing after cementing. The cement fixes the opening 7;

During operation, the device of the present invention is lowered into the bottom of the well together with the connected casing 8 (see Fig. 4) to complete the cementing operation; The K344 tool straddles the two ends of the device of the present invention, and then boosts the pressure through the oil pipe. When it reaches the rupture disk start pressure (3000-4000psi), it breaks through the rupture disk 3, and then rushes out of the pressure cap 4, and then the hydraulic pressure continues to erode at a high speed. In about a minute, the cement and rock near the pressure cap and the opening can reach a broken state, and then peel off to form holes.

Claims (4)

1. A rupture disk perforating casing coupling device, comprising a coupling body (1), characterized in that: the coupling body (1) is provided with projections (6) extending axially at intervals along the circumferential direction , each protrusion (6) is provided with several openings (7) along the radial direction, each opening (7) is provided with a nut (2), and one end of the nut (2) is connected to the bottom surface of the opening (7) A rupture disk (3) is installed between them, and a pressure cap (4) is installed on the other end of the nut (2), and the pressure cap (4) forms a certain air pressure with the nut (2) and the rupture disk (3). The upper end of the pressure cap (4) is coated with a self-dissolving softening film (5). 2. The rupture disk perforating casing collar device according to claim 1, characterized in that: the intervals between the adjacent projections (6) are 90°. 3. The rupture disk perforating casing collar device according to claim 1 or 2, characterized in that: the number of openings (7) on each protrusion (6) is 3-4. 4. The rupture disk perforating casing coupling device according to claim 1, characterized in that: the air pressure in the cavity is standard atmospheric pressure.