CN1603575A - Oil and gas well perforator interlayer gun - Google Patents

Abstract

The invention belongs to the oil gas well mining area of technology, is a kind of oil gas well shoots the air band gun. It has a tube shape gun body, gun in vivo is equipped with the central tube, in the central tube is equipped with leads explodes the rope, the band gun beginnings and ends is equipped with the belt seal structure between the gun to attach, on gun body is equipped with links up outside gun in vivo to pass the hole, between said the seal structure is located in the center to attach about the gun between. The invention band gun gun body only plays the connection role between, but seals by between the central tube and the gun attaches realizes. Because on the gun body is equipped with passes the hole, he is playing the fluid channel role, therefore among them outside does not have the differential pressure, does not withstand the working pressure, therefore, cannot distort because of the bearing, thus has avoided the card gun accident occurrence.

Description

Oil and gas well perforator interlayer gun

technical field

The invention belongs to the technical field of oil and gas well exploitation, in particular to an interlayer gun for an oil and gas well perforator.

Background technique

In the perforation of oil and gas wells, one or more interlayer guns are commonly used between two oil layers to connect the perforating guns of the two oil layers, so as to complete the perforation of the two oil layers at the same time. At present, the gun body used in the interlayer gun of the perforator not only plays the role of connection, but also plays the role of sealing, and the detonating cord in the center tube of the gun body plays the role of transmitting detonation energy. Chinese patent CN1344858 discloses a kind of perforating interlayer gun anti-pollution protection method and device, wherein the interlayer gun has a cylindrical gun body, the gun body is provided with a central tube, the central tube is provided with a detonating cord, the gun body of the interlayer gun The connection with the perforating gun or another interlayer gun is sealed through the joint between the guns, that is, there is a closed cavity between the gun body and the center pipe of the interlayer gun. When perforating, the perforator will generate high pressure when it explodes or burns in the wellbore, and this pressure is borne by the gun body. Because the gun body of the existing interlayer gun is a closed cavity, there is a pressure difference inside and outside the gun body; in addition, the pressure bearing capacity of the gun body of the existing interlayer gun is also limited. When the working pressure is high or the pressure difference between the inside and outside of the gun is large, the gun body of the interlayer gun is often flattened or caused a large deformation of the gun body, and the interlayer gun is stuck in the wellbore, resulting in a gun jam accident. The length of a single interlayer gun is related to the thickness of the interlayer between oil layers. With the increase of the length of a single interlayer gun, the pressure bearing capacity of the gun body decreases, and the possibility of gun jamming caused by the flattening of the interlayer gun body also increases. will increase accordingly.

Contents of the invention

The technical problem to be solved by the present invention is to improve the existing interlayer gun of the perforator, and provide an interlayer gun for the perforator of oil and gas wells which can avoid gun jamming accidents due to the flattening of the interlayer gun.

The technical solution to solve the above problems is: the oil and gas well perforator interlayer gun provided has a cylindrical gun body, the gun body is provided with a central tube, the central tube is provided with a detonating cord, and the two ends of the interlayer gun are provided with a sealing structure. The joint between the guns, the improvement of the present invention is that the said interlayer gun body is provided with a through hole through the inside and outside of the gun body, and the said sealing structure is arranged between the central tube and the joint between the guns. That is, the gun body of the sandwich gun of the present invention only acts as a connection, and the sealing is realized between the central tube and the joint between the guns; since the gun body is provided with a through hole, it plays the role of a fluid channel, so there is no pressure inside and outside the gun body. Poor, does not bear working pressure, therefore, it will not be deformed due to pressure; while the working pressure is borne by the center tube with small diameter and high pressure bearing capacity, so the deformation of the center tube is extremely small during application. In addition, because there is a large space between the center tube and the gun body, even if the center tube deforms during application, it will not exceed this space. After perforation, the outer diameter of the interlayer gun remains basically unchanged, that is, the radial deformation is extremely Tiny, thus avoiding the occurrence of stuck gun accidents.

When the working pressure is relatively high, the above-mentioned central pipe can be a thick-walled metal pipe, that is, the ratio of the outer diameter to the inner diameter of the central pipe is greater than or equal to 1.2.

The above-mentioned through-holes penetrating through the inside and outside of the gun body can be circular through-holes and through-holes of other shapes.

The above-mentioned sealing structure may adopt a hole groove seal, a shaft groove seal, or a tapered thread seal.

Compared with the prior art, the gun body of the present invention does not bear the working pressure, and the high pressure generated during perforation is borne by the center tube with higher pressure bearing capacity. Even if the center tube has a small amount of deformation, it has no effect on the body of the interlayer gun. Therefore, the outer diameter of the interlayer gun body remains relatively stable, which avoids the occurrence of flattening and ensures the safety of construction. Hole work.

Description of drawings

Fig. 1 is a combination diagram of the interlayer gun and the perforating gun of the present invention.

Fig. 2 is a structural diagram of an embodiment of the present invention.

Fig. 3 is a structural diagram of another embodiment of the present invention.

Detailed ways

As shown in Fig. 1 and Fig. 2: the perforator involved in the present invention includes an interlayer gun 1 and a perforating gun 2, which are connected by a joint 3 between the guns. Depending on the thickness of the interlayer between two oil layers, sometimes multiple interlayer guns need to be connected in series, and the interlayer guns are also connected through the joints between the guns. The sandwich gun 1 mainly includes a cylindrical gun body 4, a central tube 5 and a detonating cord 7 installed in the central tube 5. The two ends of the central tube 5 are inserted into the gun joint 3, and a sealing structure is arranged between the gun joint 3. The sealing structure can adopt a shaft groove sealing structure 8, that is, a sealing groove is provided on the outer surface of the central tube 5 ; The hole groove sealing structure 9 can also be used, that is, a sealing groove is opened in the inner hole of the gun joint 3 . Be threaded connection between the gun body 4 and the gun joint 3, and four through holes 6 have been opened on the gun body 4, and the inner cavity of the gun body 4 is connected with the outside. Therefore, the gun body 4 only plays a connecting role, and the sealing is realized between the central tube 5 and the joint 3 between the guns. In order to facilitate the central tube 5 into the joint 3 between guns, a centering disc 10 is also provided in the gun body 4, which plays a centering role during installation. In this example, the central pipe 5 is a thick-walled steel pipe with an outer diameter of 34 mm, an inner diameter of 16 mm, and an external pressure resistance greater than 140 MPa.

As shown in Figure 3: the central tube of the present invention can also use a pressure-bearing non-metallic hose, that is, the central tube is composed of metal tubes 51 at both ends and a non-metallic flexible tube 52 in the middle, and other structures are the same as in the previous embodiment , wherein the sealing structure adopts the shaft groove seal.

Claims (5)

1, a kind of oil-gas well perforator interlayer gun, has a tubular rifle body (4), be provided with central tube (5) in the rifle body (4), be provided with detonating fuse (7) in the central tube (5), the two ends of interlayer gun are provided with joint (3) between the rifle of being with hermetically-sealed construction, it is characterized in that said interlayer gun rifle body (4) is provided with the through hole (6) that connects the rifle inside and outside, said hermetically-sealed construction is located between central tube (5) and rifle between the joint (3).

2, as the said interlayer gun of claim 1, it is characterized in that said central tube (5) adopts metal tube, the ratio of its external diameter and internal diameter is more than or equal to 1.2.

3,, it is characterized in that said hermetically-sealed construction adopts hole grooved seal or axle grooved seal structure as claim 1 or 2 said interlayer guns.

4,, it is characterized in that said central tube is made up of the metal tube (51) at two ends and middle flexible nonmetallic tubing (52) as the said interlayer gun of claim 1.

5,, it is characterized in that said hermetically-sealed construction adopts hole grooved seal or axle grooved seal structure as the said interlayer gun of claim 4.