CN104863552A - Hydraulic orienting device for horizontal well - Google Patents

Abstract

The invention relates to a hydraulic orienting device for a horizontal well.The basic working principle is described in that a small steel ball with high density capable of freely rolling along a circumferential direction is arranged in the interior of a joint. With gravitational direction of the small ball constant, an indicate direction is provided for rotation of a perforating device under the well. When a high-pressure fluid is pumped into the shaft, joint rotation and orientation are finished at the same time. The orienting joint is capable of effectively positioning a complicated well bottom of the horizontal well with high reliability and has a simple structure and is easily prompted. The horizontal well does not have the problem of hydraulic oriented perforating. Therefore, the purpose of oriented perforating for oil reservoir is fulfilled.

Description

Horizontal Well Hydraulic Orientation Device

technical field

The invention relates to the field of oil and gas exploitation, and is a novel horizontal well hydraulic directional tool.

Background technique

Perforation completion is a commonly used well completion method in oil and gas fields. Due to its large hole diameter and depth and no compaction zone on the hole wall, hydraulic sandblasting perforation is very effective for improving the perfection of production layers, especially low-permeability oil and gas reservoirs, and increasing the drainage area. For oil and gas wells containing water layers, it is generally necessary to avoid perforating near the water layer, so as to avoid the possibility that the blasthole may directly communicate with the water layer, causing the production well to break through the water in advance and "water flood" the oil layer, resulting in a decrease in production or even a shutdown. It is relatively easy to solve this problem in vertical wells, just determine the position of the water layer according to the logging data, but in horizontal wells, when the wellbore trajectory is close to the top water or bottom water layer, it is necessary to control the perforation to keep the horizontal direction, However, the conventional uniform distribution of perforations in the circumferential direction has the risk of penetrating the water layer. Therefore, it is necessary to control the perforation direction of the hydraulic sandblasting perforation.

At present, the orientation methods of horizontal well perforation at home and abroad mainly include:

The method of using the gravity eccentric device to cooperate with the rotating joint. This technology is widely used in China. Using the principle that the direction of the eccentric counterweight is vertically downward under the action of gravity, the angle between the perforating gun and the eccentric counterweight is adjusted on the ground so that the direction of the perforating device that is lowered into the well is exactly the design orientation. The perforating device is rotated around the axis by eccentric gravity, and the eccentric positioner reaches a stable state when the resultant couple is zero. However, this method has high requirements for the following parameters, such as the size fit between the device and the casing, the length and weight of the device, the height of the fins, the friction coefficient between the device and the casing, etc.; the friction couple of the rotary joints at both ends of the device requires The well inclination angle is greater than 25°. If the well inclination angle is small, the torsion force provided by the eccentric counterweight is small, and the directional effect cannot be achieved. The construction period of oil pipe transmission is long and the labor intensity is high; the horizontal well is filled with liquid, the rotation of the device will be subject to great resistance, and it is not easy to achieve accurate positioning.

Cable transmission directional technology. In this technology, a locator with a directional key is lowered at the perforation position through the cable, and the locator is set and sealed. Then enter the gyro orientation instrument to measure the position of the orientation key of the locator. On the ground, adjust the position of the nozzle or perforating gun and the guide groove on the perforating device. When the guide groove is docked with the directional key, the perforating gun is in the required position. Although this method is accurate in positioning, when the horizontal section of the horizontal well is long, the locator and gyro measuring instrument cannot be lowered to the predetermined position through the cable; Once sealed, it cannot be taken out and cannot be reused. In addition, when multiple orientations are required, the tools need to be lifted and lowered repeatedly, and the construction efficiency is low.

Halliburton's G-Force directional technology. Its principle is to control the orientation through the gravity conical gyroscope in the sealed cavity. When the device reaches the predetermined well section, the conical gyroscope automatically determines the orientation and points to the center of the earth. At this time, it drives the lower perforating gun to rotate to the pre-designed orientation. However, this method still uses the gravity of the gyro to provide the power to rotate, and when the resistance in the well is large, it cannot be guaranteed to rotate to an accurate position.

In order to solve the orientation problem during hydraulic sandblasting and perforation of horizontal wells, the present invention designs a new type of hydraulic orientation device for horizontal wells.

Contents of the invention

The object of the present invention is to provide a tool for hydraulic orientation of horizontal wells, so as to realize precise orientation of perforations when hydraulic sand blasting perforation is carried out in horizontal well sections.

For this reason, the present invention proposes to combine the hydraulic perforation technology with the directional key technology, and after the high-pressure fluid is pumped, the perforation nozzle is accurately rotated to a predetermined direction. Its characteristics are:

The invention installs an orientation joint between the perforating device and the oil pipe to change the direction of the perforating nozzle. Inside the joint, there is a high-density steel ball that can freely roll along the ring direction. The rear end is a rotatable guide shoe. The torque generated during the contact between the guide shoe and the directional claw sleeve drives the perforating device to rotate. There is a guide groove on the top of the guide shoe, and the guide groove is a groove whose width is equal to that of the minions. After entering the perforating device, due to gravity, the pellet will be in the lowest state. The direction of gravity of the ball is fixed, which provides an indication direction for the rotation of the perforating device downhole. In the initial stages of hydraulic perforating, high-pressure fluid is pumped into the well. The high-pressure fluid pushes the claw cover and the guide shoe to move toward the lower end of the oil pipe. Under the limitation of the directional screw, the ball forms a protrusion equivalent to the directional key at the lowermost end. When the guide groove of the guide shoe is consistent with the direction of the directional key, the rotation stops, so that the perforating nozzle can be rotated to the required position accurately. After the perforation is completed, the directional joint can be restored to its original state by releasing the pressure, and the position of the hydraulic sandblasting and perforating device can be moved to repeat the operation.

The advantages of this tool combining hydraulic perforation technology and directional key technology are:

1) Use gravity for vertical positioning. The direction can be accurately determined under the complex stress environment in the well, and it can provide a reference for the rotation positioning of the perforating device.

2) Make full use of the fluid pressure in the pipe string during hydraulic perforation. It can ensure that the directional perforating device generates a large torque to make the perforating device move and rotate.

3) The device is ingenious and the structure is simple. Easy to install and use, high reliability performance.

4) The positioning and perforation can be repeated multiple times through the next tubing, and the construction efficiency is high.

Description of drawings

The following drawings illustrate and explain the present invention schematically, but do not limit the scope of the present invention.

Fig.1 Schematic diagram of the non-working state (no pressure, shrinking state) of the directional joint of the horizontal well

Figure 2 Schematic diagram of the working state of the directional joint of the horizontal well (pressurized, elongated and horizontally oriented)

Fig.3 Schematic diagram of the cross-section of the working state of the directional joint of the horizontal well

Figure 4 Schematic Diagram of Leading Slant

Explanation of reference symbols:

1. Upper joint; 2. Core tube; 3. Fixing screw; 4. Guide shoe; 5. Cylinder; 6. Compression spring 1; 7. Orientation steel ball; , seal 2; 11, directional screw; 12, pressure spring 2; 13, seal 3; 14, seal seat; 15, lower joint

Detailed ways

The interior of the horizontal well directional joint is composed of three units. They are core tube unit, shoe guide unit and orientation unit.

The core tube unit is mainly composed of the core tube 2 . Provides a channel for high pressure fluid flow. The core tube 2 has a groove at the lower end contact portion of the directional claw sleeve 8, and is connected by a directional screw 11, so that the directional claw sleeve can only move along the axis of the core tube 2. The inner diameter of the core pipe 2 is smaller than the lower joint 15, and there is a cavity between the lower joint 15 and the lower joint 15. When pumping high-pressure fluid into the well, due to the throttling effect of the nozzle, there will be high-pressure fluid in the cavity, and these high-pressure fluids will provide power for the forward and backward movement and rotation of the entire directional joint. There is an annular groove at the contact position between the core tube 2 and the claws of the directional claw sleeve, so that the steel ball 7 can slide freely.

The boot unit consists of three parts. The first part of the cylindrical body 5 . The cylinder body 5 is connected with the lower joint 15 by threads, and the lower joint is connected with the perforating device, so that the perforating device can rotate along with the rotation of the cylinder body. The upper part of cylinder body 5 is connected with guide shoe 4 by fixing screw 3 . Adjust the angle between the fixing screw 3 and the nozzle of the perforating tool on the ground, press the tool after it is lowered into the well, and the barrel drives the tool to rotate at a fixed value, so that the positioning of the nozzle in the wellbore can be realized. The second part is Yinxie 4. The connection between the guide shoe 4 and the core pipe 2 is to make the guide shoe 4 freely rotate and translate. Yinshoes are cut diagonally from a cylinder. After chamfering, groove the top to form a guide groove. The length and width of the guide groove match the length and width of the claws, and the purpose is to accommodate the protruding claws and fix the horizontal joint after rotation. A threaded hole is milled at a certain position on the top from the slot, and connected to the barrel through the fixing bolt 3. Guide shoe and cylindrical body 5 are connected by fixing bolt. The third part is stage clip 6. Stage clip 6 connects lead shoe and core tube, and stage clip promotes lead shoe motion after decompression, and lead shoe 4 can be made to return to the original initial state.

The orientation unit and the core pipe 2 are all slidingly connected. It consists of three parts. The first part is the sealing seat 14, which is responsible for sealing the space in the middle of the core tube 2, so that the high-pressure fluid generates a pressure difference, and withstands the pressure of the high-pressure fluid, and pushes the compression springs 6, 12 and the directional claw sleeve 8 to move. The second part is stage clip 12. The compression spring 12 connects the sealing seat 14 and the directional claw sleeve 8, and the directional claw sleeve 8 can be restored to the initial state after the pressure is released. The third part is the directional claw cover 8. The directional claw sleeve is made of elastic steel, and the upper part is the claw, which surrounds the core tube for a week. A groove is processed at the position corresponding to the claw body and the core tube, and an orientation steel ball 7 is placed in the groove. The steel ball 7 can only move circularly inside the groove, and can always stay at the lowest end of the groove. The lower part is the claw cover. There is a gap between the claw sleeve and the core tube 2 between the seal 9 and the seal 10 . The high-pressure fluid can push the directional claw sleeve 8 to move to the lower end of the oil pipe through the gap. When the high-pressure liquid is pumped into the core tube 2, a part of the high-pressure fluid enters the gap, and the directional claw is pushed to move along the core tube to the lower end of the oil pipe. When the elastic claws contact the steel ball 7, since the steel ball 7 is in a fixed state , elastic claws are jacked up by steel ball 7. The elastic minions form a directional key under the action of the steel ball 7.

When installing the tool, adjust the angle between the fixing bolt 3 and the nozzle of the perforating tool on the ground. After inserting the tool, the small ball 7 in the orientation joint is due to gravity, and the groove is at the lowest position. When working, pump high-pressure fluid into the tubing from the wellhead. The high-pressure fluid flows into the core tube 2, most of the high-pressure fluid enters the lower joint and the nozzle through the core tube 2, and a small part enters the gap of the directional claw sleeve 8, so that the directional claw sleeve 8 moves along the axis of the core tube, and makes the bottom of the groove Minions expand, forming directional bonds. Most of the high-pressure fluid pushes the lower sub to drive the barrel 5 to move axially along the borehole. The guide shoe 4 can rotate under the action of the guide groove. When the directional key is in contact with the guide shoe 4, the guide shoe 4 rotates, and at the same time drives the cylinder and the perforating device to rotate until the directional key enters the guide groove of the guide shoe. The orientation process ends. At this time, the perforating tool reaches and maintains the set orientation after turning through a certain angle.

When the perforation is finished, the fluid in the cavity no longer has high pressure. At this time, the stage clip 6 between the guide shoe 4 and the core tube 2 gradually returns to its original state, so that the guide shoe 4 and the cylindrical body 5 return to the original position together. The stage clip 12 between the directional claw cover 8 and the core tube 2 returns to the original state gradually, the directional key is disengaged from the guide groove, and the bead 7 gets back in the groove again. The entire directional joint is returned to its non-working condition and can be reused.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention are all acceptable. Should belong to the protection scope of the present invention.

Claims (3)

1. An automatic orienting device for hydraulic sandblasting and perforating nozzles, which is characterized in that: a steel ball that can move freely along the circular track is installed in the tool as a direction indicator, and under the action of pumped high-pressure fluid, the perforating nozzle Accurately rotate to the direction that is at a set angle with the indicator mark. 2. The automatic orientation method according to claim 1, the steel ball cooperates with a set of mechanisms with a plurality of elastic claws at one end, when the mechanism moves under the action of fluid pressure, the elastic claw at the bottom will protrude, It moves while rotating along a predetermined track of a known structure, so as to drive the downhole sandblasting and perforating tool installed with nozzles to rotate. 3. Springs are installed in the elastic claw mechanism and the predetermined track according to claim 2, so as to ensure that the mechanism returns to its original state after the fluid pressure is released, so as to be reused.