CN106437570A - Drilling type continuous sand blasting device - Google Patents

Abstract

The invention provides a drilling type continuous sand washing device, which includes a sand washing drill bit, a double-walled drill string, a rotary sealing wellhead, a rotary drive device, a sand washing fluid manifold, and a sand carrying fluid manifold; the sand washing drill includes a drill body, Drill inner body. The rotary driving device drives the double-walled drill string to rotate and drives the sand washing bit to rotate and cut the hard sand column at the bottom of the well; a high-pressure vibration chamber with multi-curved chambers is formed between the inner wall of the lower part of the drill body and the inner and outer walls of the drill bit, and a part of the high-pressure vibration chamber The high-pressure jet produced by the sand flushing fluid through the backward jet nozzle can provide suction negative pressure. On the one hand, it can ensure the normal circulation of sand in the low-pressure well. The sand liquid is sprayed out through the nozzle of the drill bit to form an asymmetrical jet flow, which facilitates the loose sand at the bottom of the well to enter the sand-carrying liquid suction chamber and improves the sand-carrying efficiency. The device can effectively complete the cleaning operation of the hard sand column of the low pressure oil well while ensuring the safety of the oil and gas well.

Description

Drilling type continuous sand washing device

technical field

The invention relates to the technical field of machinery, in particular to a drilling type continuous sand washing device.

Background technique

Formation sand production is one of the unavoidable and important problems in the development and production of oil and gas fields. Due to factors such as long production time, high recovery degree and severe reduction of reservoir pressure coefficient in oil fields in the central and eastern my country, formation sand production is particularly serious. According to statistics, the sand production wells in Jianghan Oilfield account for about 50% of the total production wells, and the number of workover operations caused by formation sand production in the oilfield accounts for 45%-50% of the total workover times, which greatly increases the production cost of the oilfield. Formation sand deposits in the wellbore to form a sand column, flooding the production layer, resulting in a decrease in production; at the same time, it wears downhole and surface production equipment, causing damage to the oil and gas well; in severe cases, it may cause the well wall to collapse and cause the oil and gas well to stop production. Therefore, during the production and development of oil and gas wells, the formation sand entering the wellbore must be removed in time.

At present, the sand cleaning technologies commonly used in the field are mainly divided into two categories: (1) hydraulic sand washing, including conventional hydraulic sand washing (forward circulation sand washing, reverse circulation sand washing, forward flushing and backwashing sand washing, etc.), low-density gasification Liquid sand washing, temporary sealing agent hydraulic sand washing, jet negative pressure sand washing, etc.; (2) mechanical sand washing, including wire rope conveying sand washing, oil pipe conveying sand washing, etc. The key to hydraulic sand washing operation is to establish circulation in the wellbore, so that the formation sand can be carried out of the well by the sand washing fluid. Leak directly into the formation; although low-density sand washing liquid or jet negative pressure sand washing can be used for normal circulation, the effect of sand cleaning on severely consolidated hard sand columns is not obvious. The mechanical sand dredging technology does not require external working fluid circulation, will not pollute the oil layer, and is easy to operate. However, when the bottom of the well is settled and consolidated to form a sand column, the sand dredging operation is often difficult to succeed.

As can be seen from the above, there is currently no effective method to solve the problem of hard sand columns produced in the production of low-pressure oil and gas wells.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned defects in the prior art, and provide a drilling type continuous sand washing device for removing hard sand columns in low-pressure oil wells.

A drilling type continuous sand washing device, comprising: a sand washing drill bit, a double-walled drill string, a rotary sealing wellhead, a rotary drive device, a sand washing fluid manifold, and a sand carrying fluid manifold;

The sand washing drill bit includes: a drill bit body and a drill bit inner body;

The upper end of the inner body of the drill bit is provided with an inner joint of the drill bit, and the inner body of the drill bit is a hollow cylinder structure. The upper section of the hollow cylinder is the upper return channel for the sand-carrying liquid, and the middle and lower sections are the suction chamber for the sand-carrying liquid;

The upper edge of the drill body constitutes the drill body joint, the lower section outside the drill body is provided with cutting ribs along the circumference, and the bottom surface of the drill body is provided with a sand-carrying liquid inlet, which communicates with the sand-carrying liquid suction chamber; The inlet of the sand liquid coincides with the axis of the drill body; a high-pressure vibration chamber with multi-curved surfaces is formed between the inner wall of the lower part of the drill body and the inner and outer walls of the drill bit, and an annular space with unequal diameters is formed between the inner wall of the upper part of the drill body and the inner and outer walls of the drill bit The annulus of the drill bit; the high-pressure oscillation chamber communicates with the annulus of the drill bit;

The lower part of the inner body of the drill bit is arranged with several pairs of backward jet nozzles, and the bottom surface of the drill bit body is arranged with several drill bit nozzles; the inlet of the backward jet nozzle is connected with the high-pressure oscillation chamber, and the outlet is located in the sand-carrying liquid suction chamber; The inlet is communicated with the high-pressure oscillation chamber, and the outlet is communicated with the wellbore outside the sand washing bit;

The double-wall drill string includes a double-wall drill pipe outer joint and a hollow double-wall drill pipe inner tube; the inner passage of the double-wall drill pipe inner tube forms a central flow channel; the bottom end of the double-wall drill pipe inner tube is set There is a double-wall drill pipe inner joint, the outer wall of the double-wall drill pipe inner pipe and the inner wall of the double-wall drill string form a double-wall drill pipe annular space, and the outlet of the double-wall drill pipe inner joint communicates with the central flow channel;

The double-walled drill string is formed by sequentially threading a plurality of double-walled drill pipes, and the outer joint of the double-walled drill pipe and the inner joint of the double-walled drill pipe are respectively threaded with the joint of the drill body and the inner joint of the drill bit; the annular space of the double-walled drill pipe It is connected with the drill bit annulus, and the double-walled drill pipe annulus is connected with the sand washing fluid manifold. The upper return channel for sand liquid is the same channel, and the central overflow channel is connected with the sand-carrying liquid manifold, and the upper return channel for sand-carrying liquid, the central overflow channel and the sand-carrying liquid manifold constitute the outlet channel for the sand-carrying liquid;

The rotary sealing wellhead is arranged on the ground, and is used for sealing and fixing the double-walled drill string on the wellhead; the rotary driving device is arranged above the ground, and is used for driving the double-walled drill string and the sand washing bit to rotate.

Further, in the above-mentioned drilling type continuous sand washing device, the inlet of the sand-carrying liquid is conical.

Furthermore, in the above-mentioned drilling type continuous sand washing device, the backward jet nozzles are symmetrically arranged, the number is 2-3 pairs, and the included angle between the backward jet nozzles and the axis of the drill body is 10°-30°.

Furthermore, in the above-mentioned drilling type continuous sand washing device, the drill bit nozzles 112 are arranged asymmetrically, and the number is 3-5.

Further, in the above-mentioned drilling type continuous sand washing device, the equivalent diameter of the drill bit nozzle is smaller than the equivalent diameter of the backward nozzle.

Further, in the above-mentioned drilling type continuous sand washing device, the cutting ribs are arranged in pairs, and the number is 2-3 pairs.

Compared with the prior art, the beneficial effects of the present invention are as follows:

(1) The rotary sand washing drill bit of the present application replaces the sand cone or sand shovel in the conventional mechanical sand dredging, and realizes that the drill bit rotates and cuts the hard sand column at the bottom of the well under the action of the drilling pressure, and removes the severely consolidated formation sand. It becomes crushed sand and loose sand, which is beneficial to the sand-carrying of the sand washing fluid and improves the efficiency of sand cleaning;

(2) The backward jet produced by the backward jet nozzle of the present application can generate suction negative pressure, which can effectively reduce the pressure difference at the bottom of the well. The sand is separated from the bottom of the well, improving the efficiency of sand washing;

(3) The high-pressure oscillating chamber of the present application has the effect of oscillating backflow, where the sand washing fluid generates a vortex, and the vortex disturbance interacts with the collision wall, thereby increasing the energy of the fluid at the outlet of the backward jet nozzle and the drill nozzle, which is beneficial to sand washing and carrying sand.

Description of drawings

Fig. 1 is a structural schematic diagram of a drilling type continuous sand washing device of the present invention;

Fig. 2 is a schematic structural view of a sand washing drill bit of a drilling type continuous sand washing device of the present invention;

Fig. 3 is a three-dimensional schematic diagram of a sand washing drill bit of a drilling type continuous sand washing device of the present invention;

Fig. 4 is a structural schematic diagram of a double-walled drill pipe of a drilling type continuous sand washing device of the present invention.

In the figure: 1. Sand washing drill bit, 2. Wellbore, 3. Double-walled drill string, 4. Surface, 5. Rotary sealing wellhead, 6. Rotary drive device, 7. Sand washing fluid manifold, 8. Sand carrying liquid pipe Sink, 11, drill bit inner joint, 12, drill bit inner body, 13, drill bit body, 14, drill bit body joint, 15, drill bit annular space, 16, sand-carrying liquid suction cavity, 17, sand-carrying liquid upper return channel, 18, High-pressure oscillation chamber, 19, backward jet nozzle, 110, cutting wing rib, 111, sand-carrying liquid inlet, 112, drill bit nozzle, 31, double-wall drill pipe outer joint, 32, double-wall drill pipe inner joint, 33, double-wall drill pipe Annulus of wall drill pipe, 34, inner tube of double-wall drill pipe, 35, center flow channel.

detailed description

In order to make the purpose, technical solutions and advantages of the present invention clearer, the following technical solutions in the present invention are clearly and completely described. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

As shown in Figures 1-4, the drillable continuous sand washing device of the present invention includes a sand washing drill bit 1, a double-walled drill string 3, a rotary sealing wellhead 5, a rotary drive device 6, a sand washing fluid manifold 7, and Sand liquid manifold 8.

The sand washing drill bit 1 includes a drill bit body 13, a drill bit body joint 14, a drill bit inner body 12, a drill bit inner joint 11, a cutting rib 110, a drill bit annular space 15, a high-pressure vibration cavity 18, a backward jet nozzle 19, a drill bit nozzle 112, and a Sand inlet 111, sand-carrying liquid suction chamber 16, and sand-carrying liquid upward return channel 17. The lower part of the outer side of the drill body 13 is arranged with two pairs of cutting ribs 110 along the circumferential direction; the inner body 12 of the drill bit is a hollow cylinder, the upper part of the hollow cylinder is the upper return channel 17 for the sand-carrying liquid, and the lower part of the hollow cylinder is the suction chamber for the sand-carrying liquid 16. The sand-carrying liquid inlet 111 is conical and located on the bottom surface of the drill body 13, and communicates with the sand-carrying liquid suction chamber 16, and the sand-carrying liquid inlet 111 coincides with the axis of the drill body 13. The drill bit annulus 15 is an annular space with unequal diameters formed between the inner wall of the upper section of the drill body 13 and the outer wall of the drill inner body 12; the high-pressure oscillation chamber 18 is a multi-curved chamber formed between the inner wall of the lower section of the drill body 13 and the outer wall of the drill inner body 12 , the drill bit annulus 15 communicates with the high-pressure oscillating cavity 18; the lower part of the drill bit inner body 12 is arranged with 3 pairs of backward jet nozzles 19, the axis of the backward jet nozzles 19 and the axis of the drill body 13 form an angle of 30°, and the backward jet flow The inlet of the nozzle 19 communicates with the high-pressure oscillation chamber 18, the outlet of the backward jet nozzle 19 is located in the sand-carrying liquid suction chamber 16, and the outlet of the backward jet nozzle 19 is located in the same plane of the sand-carrying liquid suction chamber 16; Five drill nozzles 112 are arranged asymmetrically on the bottom surface. The inlets of the drill nozzles 112 communicate with the high-pressure oscillation chamber 18 , and the outlets of the drill nozzles 112 communicate with the wellbore 2 .

The double-walled drill string 3 includes: a double-walled drill pipe outer joint 31 , a double-walled drill pipe inner joint 32 , a double-walled drill pipe annular space 33 , a double-walled drill pipe inner pipe 34 , and a central flow channel 35 . The double-walled drill string 3 is formed by sequentially threading a plurality of double-walled drill rods, and the double-walled drill pipe outer joint 31 and the double-walled drill pipe inner joint at the lowest end of the double-walled drill string 3 are respectively connected to the drill body joint of the sand washing drill bit 1 14 and drill bit inner joint 11 are threadedly connected with 32 respectively; the double-walled drill pipe annulus 33 communicates with the drill bit annulus 15, and the double-walled drill pipe annulus 33 at the uppermost end of the double-walled drill string 3 communicates with the sand washing fluid manifold 7, The drill bit annulus 15, the double-walled drill pipe annulus 33 and the sand washing fluid manifold 7 constitute the channel for the sand washing fluid to enter the well; 17 are connected, and the central flow channel 35 of the double-wall drill pipe inner tube 34 at the uppermost end of the double-wall drill string 3 is connected with the sand-carrying liquid manifold 8, and the sand-carrying liquid upward return channel 17, the central flow channel 35 and the sand-carrying liquid The liquid manifold 8 constitutes the outlet channel for the sand-carrying liquid. The rotary sealing wellhead 5 is installed on the ground 4 to ensure the safety of the sand dredging operation; the rotary drive device 6 is mainly used to drive the entire drilling string to rotate during the operation.

The working process and working principle of using this device to wash the hard sand column of low-pressure oil and gas wells are as follows:

When performing sand washing operations, first measure the depth of the top surface of the hard sand column in the wellbore, determine the number of double-walled drill pipes to be used according to the depth, and then assemble the drill string into the well, and run the assembled string into the well Wellbore 2. When the sand washing bit 1 touches the hard sand column at the bottom of the well, start the rotary drive device 6 to drive the double-walled drill string 3 and the sand washing bit 1 to rotate, and the sand washing bit 1 starts to cut the hard sand column at the bottom of the well, so that the severely consolidated The formation sand becomes crushed sand and loose sand; at the same time, the sand washing liquid is pumped from the sand washing liquid manifold 7. The high-pressure sand washing fluid enters the double-wall drill pipe annulus 33 of the double-wall drill string 3 through the sand washing fluid manifold 7, and then enters the high-pressure oscillation chamber 18 through the drill bit annulus 15. A part of the high-pressure sand washing fluid entering the high-pressure oscillation chamber 18 is ejected from the backward jet nozzle 19 to form a high-speed jet, which generates negative pressure in the sand-carrying fluid suction chamber 16, and the negative pressure impacts on the wellbore 2 through the sand-carrying fluid inlet 111. The sand liquid and broken sand are sucked; at the same time, another part of the high-pressure sand-carrying liquid in the high-pressure oscillation chamber 18 is ejected from the drill bit nozzle 112 to stir the broken sand and loose sand produced at the bottom of the well, so that the sand at the bottom of the well is cleared during the cleaning of the sand washing liquid. Under the action of rock and the negative pressure of the sand-carrying liquid suction chamber 16, the sand-carrying liquid enters the upper return channel 17, and then circulates out of the well along the central flow channel 35 and the sand-carrying liquid manifold 8. As the sand washing bit 1 continuously cuts the hard sand column at the bottom of the well, the formation sand is carried by the sand washing fluid and continuously exits the well, thereby completing the sand cleaning process of the hard sand column of the low-pressure oil and gas well.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (6)

1. A drilling type continuous sand washing device, characterized in that it comprises: sand washing drill bit (1), double-walled drill string (3), rotary sealing wellhead (5), rotary driving device (6), sand washing liquid Manifold (7), sand-carrying liquid manifold (8); The sand washing drill bit (1) comprises: a drill bit body (13), a drill bit inner body (12); The upper end of the drill bit inner body (12) is provided with a drill bit inner joint (11), and the drill bit inner body (12) is a hollow cylinder structure. Sand fluid suction cavity (16); The upper edge of the drill body (13) constitutes the drill body joint (14), the lower section of the drill body (13) outside is circumferentially arranged with cutting ribs (110), and the bottom surface of the drill body (13) is provided with a sand-carrying liquid inlet ( 111), the sand-carrying liquid inlet (111) is connected with the sand-carrying liquid suction chamber (16); the sand-carrying liquid inlet (111) coincides with the axis of the drill body (13); A high-pressure oscillating chamber (18) with multi-curved chambers is formed between the outer walls of the body (12), and a drill annulus ( 15); the high-pressure oscillation chamber (18) communicates with the drill bit annulus (15); The lower part of the drill inner body (12) is arranged with several pairs of backward jet nozzles (19), and the bottom surface of the drill body (13) is arranged with several drill nozzles (112); The chamber (18) is connected, and the outlet is located in the sand-carrying liquid suction chamber (16); the inlet of the drill bit nozzle (112) is connected with the high-pressure oscillation chamber (18), and the outlet is connected to the wellbore (2) outside the sand washing drill bit (1). connected; The double-walled drill string (3) includes a double-walled drill pipe outer joint (31) and a hollow double-walled drill pipe inner pipe (34); the inner channel of the double-walled drill pipe (34) constitutes a central through-flow Road (35); the bottom end of the double-wall drill pipe inner pipe (34) is provided with a double-wall drill pipe inner joint (32), and the outer wall of the double-wall drill pipe inner pipe (34) and the double-wall drill pipe (3) The inner wall of the double-walled drill pipe annulus (33), the outlet of the double-walled drill pipe inner joint (32) communicates with the central flow channel (35); The double-walled drill string (3) is formed by sequentially threading a plurality of double-walled drill pipes, and the double-walled drill pipe outer joint (31) and the double-walled drill pipe inner joint (32) are respectively connected with the drill body joint (14) and The drill bit inner joint (11) is threaded; the double-walled drill pipe annulus (33) communicates with the drill bit annulus (15), the double-walled drill pipe annulus (33) communicates with the sand washing fluid manifold (7), and the drill bit annulus Hollow (15), double-walled drill pipe annulus (33) and sand washing fluid manifold (7) constitute the channel for sand washing fluid to enter the well; the central flow channel (35) is the same channel as the sand-carrying fluid upward return channel (17), The central flow channel (35) is connected with the sand-carrying liquid manifold (8), and the sand-carrying liquid upward return channel (17), the central flow channel (35) and the sand-carrying liquid manifold (8) constitute the sand-carrying liquid exit well channel; The rotary sealing wellhead (5) is arranged on the ground for sealing and fixing the double-walled drill string (3) on the wellhead; the rotary drive device (6) is arranged above the ground for driving the double-walled drill string (3) and sand flushing The drill bit (1) rotates. 2. The drilling type continuous sand washing device according to claim 1, characterized in that, the sand-carrying liquid inlet (111) is conical. 3. The drilling type continuous sand washing device according to claim 1, characterized in that, the backward jet nozzles (19) are symmetrically arranged, and the number is 2-3 pairs, and the backward jet nozzles (19) are connected with the drill bit The included angle of the axis of the body (13) is 10°-30°. 4. The drilling type continuous sand washing device according to claim 1, characterized in that the drill bit nozzles (112) are arranged asymmetrically, and the number is 3-5. 5. The drilling type continuous sand washing device according to claim 1, characterized in that, the equivalent diameter of the drill bit nozzle (112) is smaller than the equivalent diameter of the backward nozzle. 6. The drilling type continuous sand washing device according to claim 1, characterized in that, the cutting ribs (110) are arranged in pairs, and the number is 2-3 pairs.