CN104832137B - closed detonator - Google Patents

Abstract

The invention provides a closed initiator, comprising: a body; the hydraulic cylinder is sleeved in the body; the through hole is arranged on the side wall of the body and is communicated with the outer side of the hydraulic cylinder and the inner cavity; the spring is pressed against the inner side wall of the hydraulic cylinder, and the extension direction of the spring is in the axial direction of the body; an inner tube disposed within the body, and the hydraulic cylinder is located between the inner tube and the body; an initiator disposed within the body and located outside the inner tube; a detonating cord disposed within the body and connected to the initiator. After the oil pipe is put into the oil pipe and the perforating string is conveyed, the circulating channels inside and outside the oil pipe string can be established before and after the perforating string is detonated, so that the circulating well washing or killing operation can be carried out, and the potential safety hazard is eliminated.

Description

closed detonator

technical field

The invention relates to the field of oil and gas field development perforation, in particular to a closed detonator used in oil and gas well tubing transmission perforation technology.

Background technique

At present, in the field of perforating in oil and gas fields, the perforation operation can be performed on one or more layers of perforated well sections in one perforation perforation perforated by tubing transmission, and the well section perforated at one time can reach tens to hundreds of meters. The most important thing is that it can effectively prevent blowout.

The initiators used in tubing transmission perforation are mainly open-type sand-proof impact initiators and closed-type impact initiators. Open-type sand-proof impact initiators are mainly used in oil and gas wells with clean wellbores and no sand production. The closed percussion detonator is mainly used in oil and gas wells with a lot of impurities in the wellbore and thick oil. After the heavy oil or impurities enter the tubing string, it will affect the depth calibration and rod throwing links in the perforation operation. If the stick is not in place, there is a serious safety hazard.

However, after the existing closed impact detonator is detonated, the liquid inside and outside the tubing cannot circulate, and the circulation and flushing cannot be performed. When the tubing string is lifted, the liquid in the tubing will flow on the well site, polluting the environment. If the pressure in the wellbore is high, it will be impossible to pull out the pipe string in the wellbore or perform other operations, resulting in serious accidents such as overhaul.

To sum up, there are at least the following problems in the prior art: the liquid inside and outside the oil pipe of the closed detonator cannot circulate.

Contents of the invention

The invention provides a closed detonator to solve the problem that the liquid inside and outside the oil pipe of the closed detonator cannot circulate.

For this reason, the present invention proposes a kind of closed detonator, and described closed detonator comprises:

The body is cylindrical;

The hydraulic cylinder is socketed in the body, and the hydraulic cylinder includes: a moving end, a bottom plug, an outer side wall and an inner side wall arranged between the moving end and the bottom plug, and a Lumen between plug, lateral wall and medial wall;

The moving end is located at the top of the inner cavity and can slide along the axial direction of the body; the bottom plug is fixed at the bottom of the inner cavity;

Both the moving end and the bottom plug close the end of the inner cavity, the moving end is stuck in the body through a shoulder, and a sealing ring is provided on the outside of the moving end; the outer wall of the liquid cylinder is Open structure, the inner wall of the liquid cylinder, the moving end and the bottom plug form a closed structure;

A through hole is provided on the side wall of the body, and the through hole communicates with the outside of the liquid cylinder and the inner cavity;

A spring is pressed against the inner wall of the hydraulic cylinder, and the expansion and contraction direction of the spring is the axial direction of the body;

an inner tube disposed in the body, and the liquid cylinder is located between the inner tube and the body;

a detonator disposed within the body and outside the inner tube;

The detonating cord is arranged in the body and connected to the detonator.

Further, the closed detonator includes: an upper joint connected to the top of the body.

Further, the closed detonator includes: a lower joint connected to the bottom of the body.

Further, the closed detonator includes: a filter screen arranged between the through hole and the inner chamber.

Further, the outer wall of the hydraulic cylinder is open.

Further, the length of the inner tube is smaller than the length of the body.

Further, the inner tube is arranged coaxially with the body, and the moving end can slide between the inner tube and the body.

Further, the through holes are a plurality of round holes.

Further, the lower joint is connected with the perforating gun.

The purpose of the present invention is to overcome the disadvantages of traditional detonators by proposing a closed detonator. After the oil pipe is lowered to transmit the perforation string, a circulation channel inside and outside the oil pipe string can be established before and after the detonation, so as to carry out circulation flushing or Well killing operations to eliminate potential safety hazards. In the present invention, when the pressure inside the tubing string is lower than the pressure outside the tubing string, the hydraulic cylinder moves up under the force of the spring, the sealing ring of the hydraulic cylinder and the body are in contact with each other to seal, and the liquid and impurities outside the tubing string It cannot flow into the inside of the tubing string, which ensures the cleanliness of the tubing string. Thereby, it is ensured that the depth correction in the perforation operation is carried out smoothly, and it is also ensured that the percussion rod can smoothly hit the detonator when the rod is thrown, and the perforation operation is completed. When the pressure inside the tubing string is greater than the pressure outside the tubing string, a downward pressure is generated to compress the spring so that the sealing ring of the hydraulic cylinder does not seal with the body, and the liquid can realize internal and external communication. In this way, a circulation channel can be established to carry out well washing or well killing operations, ensuring complete construction and preventing accidents.

Description of drawings

Fig. 1 is a schematic diagram of the internal structure of the closed detonator of the present invention.

Explanation of reference numbers:

1 upper joint, 2 body, 3 detonator, 4 liquid cylinder, 5 filter, 6 inner tube, 7 bottom plug, 8 spring, 9 lower joint, 10 detonating cord 20 through hole 40 inner cavity 41 moving end 43 inner wall 45 outer wall

detailed description

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the present invention will now be described with reference to the accompanying drawings.

As shown in Figure 1, the closed detonator (also referred to as the recyclable closed detonator) of the embodiment of the present invention comprises:

The body 2 is cylindrical, such as cylindrical;

The hydraulic cylinder 4 is socketed in the body 2. The hydraulic cylinder is also called a hydraulic cylinder. The hydraulic cylinder includes: a moving end 41, a bottom plug 7, and an outer wall 45 arranged between the moving end and the bottom plug 7 and the inner side wall 43, and the inner cavity 40 arranged between the moving end, the bottom plug 7, the outer side wall and the inner side wall;

The moving end 41 is located at the top of the inner cavity 40 and can slide downward (towards the bottom plug 7) along the axial direction of the body 2; the bottom plug 7 is fixed at the bottom of the inner cavity and sealed The bottom end of the inner cavity is sealed with a ring;

Both the moving end 41 and the bottom plug 7 close the end of the inner cavity, and the moving end 41 is stuck in the body 2 through a shoulder to prevent the moving end 41 from sliding upwards, so that the hydraulic cylinder 4 can only move in one direction. sliding; and the outside of the moving end 41 is provided with a sealing ring; the outer wall 45 of the liquid cylinder is an open structure, for example, the outer wall 45 is an opening or a side plate with a through hole, and the inner side of the liquid cylinder The wall, the moving end and the bottom plug 7 form a closed structure;

The through hole 20 is arranged on the side wall of the body 2, and the through hole communicates with the outside of the liquid cylinder 4 and the inner cavity 40; the through hole is a plurality of round holes, which is convenient for manufacture;

The spring 8 is pressed against the bottom of the inner side wall 43 of the hydraulic cylinder, and the stretching direction of the spring 8 is the axial direction of the body 2; the hydraulic cylinder and the spring cooperate with each other, and a circulation channel can be established before and after detonation of the detonator , carry out well washing or killing operations, so that the next operation can be carried out;

The inner tube 6 is arranged in the body 2, and the hydraulic cylinder 4 is located between the inner tube 6 and the body 2;

The detonator 3 is arranged in the body 2 and is located outside the inner tube 6;

The detonating cord 10 is arranged in the body 2 , and the detonating cord 10 passes through the inner tube 6 to connect with the detonator 3 .

When the pressure inside the tubing string is lower than the pressure outside the tubing string, the hydraulic cylinder moves up under the force of the spring, the sealing ring of the hydraulic cylinder and the body are in contact with each other to seal, and the liquid and impurities outside the tubing string cannot flow into the tubing The inside of the column ensures the cleanliness of the tubing string. Thereby, it is ensured that the depth correction in the perforation operation is carried out smoothly, and it is also ensured that the percussion rod can smoothly hit the detonator when the rod is thrown, and the perforation operation is completed. When the pressure inside the tubing string is greater than the pressure outside the tubing string, a downward pressure is generated to compress the spring so that the sealing ring of the hydraulic cylinder does not seal with the body, and the liquid can realize internal and external communication. In this way, a circulation channel can be established to carry out well washing or well killing operations, ensuring complete construction and preventing accidents.

Further, the closed detonator includes: an upper joint 1 connected to the top of the body 2 . The upper sub connects to the string of the lower-incidence perforating gun.

Further, the closed detonator includes: a lower joint 9 connected to the bottom of the body 2 for connection. Further, the lower joint is connected with a perforating gun to realize perforation.

Further, the closed detonator includes: a filter screen 5 arranged between the through hole and the inner cavity, and the filter screen 5 functions to filter impurities. The liquid and impurities outside the tubing string cannot flow into the inside of the tubing string, which ensures the cleanliness of the tubing string.

Further, the outer side wall of the liquid cylinder is open, which is convenient for manufacture.

Further, the length of the inner tube 6 is shorter than the length of the body 2, so that the liquid in the inner tube 6 can flow to the moving end 41, so that the moving end 41 is subjected to the external pressure of the liquid in the inner tube 6 above, and moves End 41 is under internal pressure from lumen 40 . Because the external pressure of the liquid in the inner pipe 6 and the internal pressure from the inner cavity 40 both act on the moving end 41, therefore, the pressures inside the tubing string and outside the tubing string act on the same area on the 4 hydraulic cylinders, which can realize Circulation inside and outside the tubing string when the internal and external pressures are different.

Further, the inner tube 6 is arranged coaxially with the body 2 , and the moving end can slide between the inner tube 6 and the body 2 . In this way, it is convenient for sealing and installation.

The working principle of the present invention is: the upper joint 1 is connected with the pipe string of the lower penetration gun, and is threadedly connected with the body 2 (the body 2 is, for example, a stainless steel round pipe). The lower joint 9 is connected with the perforating gun. A circular hole is arranged on the body 2, and a filter screen 5 is arranged below the circular hole. There are sealing grooves on the inner and outer diameters of the hydraulic cylinder 4, and the sealing with the body 2 and the inner pipe 6 is realized by the sealing ring. The hydraulic cylinder 4 is stuck on the body 2 through a shoulder, and cannot be moved up, but can only be moved down or fixed. The cylinder 4 and the spring 8 are in contact with each other. The pressure inside the tubing string and the outside of the tubing string act on the same area on the hydraulic cylinder 4. When the pressure inside the tubing string is greater than the pressure outside the tubing string, a downward pressure is generated to compress the spring 8 and make the hydraulic cylinder 4 There is no sealing effect between the sealing ring and the body 2, and the liquid can realize internal and external communication.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Because the various components of the present invention can be combined with each other under the condition of no conflict, any equivalent changes and modifications made by any person skilled in the art without departing from the concept and principle of the present invention shall belong to the protection of the present invention. range.

Claims (9)

1. a kind of closed initiator, it is characterised in that the closed initiator includes：

Body (2), is tubular；

Fluid cylinder (4), is socketed in the body (2), the fluid cylinder includes：Mobile terminal, bottom block up (7), are arranged on the mobile terminal The lateral wall between (7) and madial wall, which are blocked up, the bottom of and the mobile terminal, bottom is arranged on blocks up between (7), lateral wall and madial wall Inner chamber；

The mobile terminal be located at the inner chamber top and can along the body (2) axially downwardly slip；The bottom is blocked up (7) it is fixed on the bottom of the inner chamber；

The end that (7) close the inner chamber is blocked up in the mobile terminal bottom of with, and the mobile terminal is stuck in the body by shoulder, And the outside of the mobile terminal is provided with sealing ring；The lateral wall of the fluid cylinder be Open architecture, the madial wall of the fluid cylinder, The mobile terminal blocks up (7) bottom of with and forms enclosed construction；

On through hole, the side wall for being arranged on the body (2), and the through hole connects the outside of the fluid cylinder (4) and described interior Chamber；

On spring (8), the madial wall for being pressed on the fluid cylinder, the telescopic direction of the spring (8) is the axle of the body (2) To；

Inner tube (6), is arranged in the body (2), and the fluid cylinder (4) be located at said inner tube (6) and the body (2) it Between；

Initiator (3), is arranged in the body (2), and outside said inner tube (6)；

Primacord (10), is arranged in the body (2), and connect the initiator (3).

2. closed initiator as claimed in claim 1, it is characterised in that the closed initiator also includes：It is connected to Top connection (1) at the top of the body (2).

3. closed initiator as claimed in claim 1, it is characterised in that the closed initiator also includes：It is connected to The lower contact (9) of body (2) bottom.

4. closed initiator as claimed in claim 1, it is characterised in that the closed initiator also includes：Screen pack (5), it is arranged between the through hole and the inner chamber.

5. closed initiator as claimed in claim 1, it is characterised in that the lateral wall of the fluid cylinder is opening.

6. closed initiator as claimed in claim 1, it is characterised in that the length of said inner tube (6) is less than the body (2) length.

7. closed initiator as claimed in claim 1, it is characterised in that said inner tube (6) with the body (2) is coaxial sets Put, and the mobile terminal can be slided between said inner tube (6) and the body (2).

8. closed initiator as claimed in claim 1, it is characterised in that the through hole is multiple circular holes.

9. closed initiator as claimed in claim 3, it is characterised in that the lower contact is connected with perforating gun.