CN115680607A - Underground bit pressure torque measuring system - Google Patents

Abstract

The invention discloses a downhole pressure-on-drilling torque measurement system, which belongs to the field of petroleum drilling and well logging, and comprises a drill collar body, a strain gauge embedded block and a sealing gland. The surface of the drill collar body is provided with a measuring groove, and the sealing gland The strain gauge embedded block is press-fitted in the measuring groove in the form of interference fit; the strain gauge embedded block includes the embedded block body, the drilling pressure strain gauge and the torque strain gauge arranged on the embedded block body, and the upper end of the embedded block body is It is in contact with the sealing gland, and the lower end is in contact with the drill collar body. Through the independently designed strain gauge embedding block, the present invention solves the problems in the prior art such as complex patching process, inconvenient operation in the corresponding narrow hole position on the drill collar, poor patch installation position accuracy, and complicated correction calculations, etc. The production efficiency is improved, and the product production is not restricted by the size of the calibration and heating equipment, and has good popularization and application.

Description

A downhole pressure-on-bit torque measurement system

technical field

The invention relates to the technical field of petroleum drilling, in particular to a downhole pressure-on-drilling torque measurement system.

Background technique

With the development of drilling engineering, the monitoring of downhole drilling safety parameters has become one of the necessary links in the drilling process. The measurement of WOB and torque plays an important role and significance for the safety of downhole drilling tools, the safety and quality of boreholes, the dragging pressure of the horizontal section in extended-reach horizontal wells, and the calculation and analysis of the force of drilling tools. Conventional downhole weight-on-bit torque measurement generally has problems such as complicated patching process, inconvenient operation in the corresponding hole position on the drill collar, poor position accuracy, and complicated correction calculation.

For example, in the prior art, the patent CN113482597A discloses an automatic monitoring device for geological core drilling parameters at the bottom of a hole. The device includes: a measuring pup body, a power supply module and a measurement module for drilling parameters at the bottom of a hole. Measuring pup body, the upper end is connected with the drill pipe, the lower end is connected with the drill bit, the inside is hollow, and a measuring groove is opened in the outer wall. The hole bottom drilling parameter measurement module is sealed in the measurement groove, including at least one of a hole inclination module, a speed module, a temperature module, a drilling pressure and torque module, an outer annular air pressure module, and an inner annular air pressure module. Hole inclination module, speed module, temperature module, pressure on bit and torque module, outer annular air pressure module, inner annular air module are used to measure hole inclination, rotational speed, hole bottom temperature, hole bottom pressure on bit and drilling torque, outer ring Air pressure and inner annular air pressure.

The engineering parameter mounting method of the above-mentioned patent is to process four uniformly distributed mounting grooves in the circumferential direction on the body of the engineering parameter short joint, and after polishing the mounting area, use tweezers and other tools to glue the strain gauge to the corresponding area. However, the patch tank generally has a small space, which leads to poor operability and difficult alignment. After patching, it needs to use a large temperature box and other equipment for heating and curing, which takes a long time for curing and product production. And if the strain gauge is damaged, it needs to be pasted again, the process of removing the old piece is complicated, and the entire drill collar needs to be returned to the factory for repair.

Contents of the invention

The invention aims to solve the problems of complex patching process and inconvenient operation in the engineering parameter monitoring device in the prior art, and proposes a downhole drilling pressure torque measurement system. The production is not restricted by the size of the calibration and heating equipment, which improves the measurement accuracy of the weight-on-bit torque calibration, and also improves the efficiency of product production and maintenance.

In order to realize the above-mentioned purpose of the invention, the technical scheme of the present invention is as follows:

A downhole pressure-on-bit torque measurement system, characterized in that it includes a drill collar body, a strain gauge embedded block and a sealing gland, the surface of the drill collar body is provided with a measuring groove, and the sealing gland inserts the strain gauge into the block to Press-fit in the measuring groove in the form of an interference fit; the strain gauge embedding block includes an embedding block body, a drilling pressure strain gauge and a torque strain gauge arranged on the embedding block body, the upper end of the embedding block body is in contact with the sealing gland, and the lower end is in contact with the sealing gland. Contact with drill collar body.

Further, the embedding block body includes two cylindrical bodies with different diameters, and the large-diameter cylindrical body and the small-diameter cylindrical body are coaxially connected to form a boss structure.

Further, the pressure-on-bit strain gauges and torque strain gauges are distributed on the stepped surface formed by the large-diameter cylindrical body and the small-diameter cylindrical body.

Further, the pressure-on-bit strain gauges and torque strain gauges are evenly spaced along the circumference of the stepped surface to form a strain gauge sensor array.

Further, four measuring grooves are arranged on the same radial section plane of the drill collar body, and these four measuring grooves are evenly distributed on the cross orientation of the radial section plane.

Further, the four sets of strain gauges corresponding to the four measuring slots are connected by bridges to eliminate mutual influence.

Further, the material of the embedded block body has a higher modulus of elasticity than the material of the drill collar body.

Further, the sealing gland is provided with a circlip to limit its axial movement, and the gap between the sealing gland and the measuring tank is sealed with a sealing ring.

Further, it also includes a battery pack and a circuit connected to the strain gauges arranged inside the drill collar body, and a battery board and a circuit board are respectively arranged on the surface of the drill collar body corresponding to the battery pack and the circuit.

Further, the bottom of the embedding block body is provided with a positioning pin hole, and the bottom of the measuring groove is provided with a positioning pin shaft, and the positioning pin hole cooperates with the positioning pin shaft to prevent the strain gauge embedding block from rotating.

In summary, the present invention has the following advantages:

1. The present invention can realize patching and calibration on the outside of the drill collar by setting an independent strain gauge embedding block. After the calibration is completed, it is assembled with the drill collar body by interference fit. At the same time, the upper gland and the pillar above the embedding block Contact, which can reduce the influence of inner and outer annular pressure on the measurement of weight-on-bit torque;

2. The strain gauge embedding block of the present invention is independently designed, and can be accurately calibrated by using a small drilling pressure torque platform. It also avoids the long-term high-temperature curing operation of the strain gauge adhesive in the oven after the drill collar is pasted, shortening the The curing time improves the production efficiency, so that the production of the product is not restricted by the size of the calibration and heating equipment;

3. The present invention can increase the strain amount by changing the material and shape of the strain gauge embedded block to improve the measurement accuracy;

4. The weight-on-bit torque measurement system of the present invention has high measurement accuracy, convenient assembly and maintenance, simple and convenient calibration, and high applicability.

Description of drawings

1 is a schematic diagram of the internal structure of the WOB torque measurement system of the present invention;

Fig. 2 is the A-A cut-away schematic diagram of Fig. 1;

Fig. 3 is a top view structural schematic diagram of a strain gauge embedding block;

Fig. 4 is a side view structural schematic diagram of the strain gauge embedding block;

Figure 5 shows the bridge connection mode of the pressure-on-bit torque strain gauge.

In the picture:

1. Drill collar body; 2. Strain gauge insert block; 3. Sealing gland; 4. Circlip; 5. Sealing ring I; 6. Sealing ring II; 7. Battery pack; 8. Circuit; 9. Battery cover ; 10, circuit cover plate; 21, embedded block body; 22, drilling pressure strain gauge; 23, torque strain gauge; 40, first amplifier; 42, second amplifier, 30, filter, 32, rectifier, 50, digital output port.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention. 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.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "vertical", "inner", "outer" etc. is based on the orientation or positional relationship shown in the drawings, or is The usual orientation or positional relationship of the product of the invention in use, or the orientation or positional relationship commonly understood by those skilled in the art, is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device or element Must be in a particular orientation, be constructed in a particular orientation, and operate in a particular orientation, and therefore should not be construed as limiting the invention. In addition, the terms "first", "second", etc. are only used for distinguishing descriptions, and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be interpreted in a broad sense, for example, it can be a fixed connection or an optional connection. Detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

Example 1

The present invention provides a downhole pressure-on-bit torque measurement system, which includes a drill collar body 1, a strain gauge embedded block 2, a sealing gland 3, a retaining spring 4, a battery pack 7, a circuit 8, a battery cover 9 and a circuit cover 10 . The battery pack 7 and the circuit 8 are arranged inside the drill collar body 1 and are electrically connected with the strain gauges.

Several measuring grooves are opened on the surface of the drill collar body 1 for installing strain gauge insert blocks 2 . Specifically, as shown in Figure 2, the measuring grooves are evenly distributed on the periphery of the surface of the drill collar body 1, and four measuring grooves are arranged on the same radial section surface of the drill collar body 1, and each measuring groove is arranged along its depth direction. Step-shaped variable diameter structure with outer width and inner narrowness. The strain gauge embedded block 2 is located at the bottom of the measuring groove and is in contact with the drill collar body 1 . During installation, the sealing gland 3 press-fits the strain gauge embedded block 2 in the measuring groove in an interference fit manner.

As shown in FIGS. 3 and 4 , the strain gauge embedding block 2 includes an embedding block body 21 , a pressure-on-bit strain gauge 22 and a torque strain gauge 23 .

Wherein, the embedding block body 21 includes two cylindrical bodies with different diameters, and the large-diameter cylindrical body and the small-diameter cylindrical body are coaxially connected to form a boss structure. The pressure-on-bit strain gauges 22 and torque strain gauges 23 are evenly spaced on the stepped surface formed by the two columns, forming a strain gauge sensor array distributed along the circumferential direction of the stepped surface. In this embodiment, the strain gauges of Zhonghang Electronics can be used.

As shown in Figure 2, specifically, a sealing gland 3 is also provided in the measuring tank, and a retaining spring 4 is arranged on the sealing cap to limit its axial movement, and the sealing gland 3 cooperates with the retaining spring 4 to embed the strain gauge The block 2 is press-fitted in the measuring tank, and the gap between the sealing gland 3 and the measuring tank is sealed with a sealing ring.

Before installation, the strain gauge embedded block 2 is pasted and calibrated on the outside. After the calibration is completed, it is assembled with the drill collar body 1 by interference fit. At the same time, the upper sealing gland 3 is in contact with the top of the strain gauge embedded block 2, which can reduce the Influence of inner and outer annular pressure on weight-on-bit torque measurement.

Further, in order to better implement this solution, the bottom of the embedding block body is provided with a positioning pin hole, and the bottom of the measuring groove is provided with a positioning pin shaft, and the positioning pin hole and the positioning pin shaft are used to prevent the rotation of the strain gauge embedding block The resulting torque measurement error.

Further, the embedded block body 21 can be made of a material with a higher elastic coefficient than the drill collar body 1, so that the strain amount changes greatly and the measurement accuracy is easy to improve.

In this embodiment, the strain gauge embedding block 2 can be calibrated with a small calibration tool independently, so as to realize the precise application of the calibration force and avoid the reduction of the measurement accuracy of the instrument caused by the force application error of the large calibration equipment. After the strain gauge embedding block 2 is calibrated, it is embedded in the engineering parameter body by crimping, and the two adopt interference fit.

Example 2

On the basis of Example 1, further, in order to better implement this solution, as shown in Figure 3, the design of four groups of patch bridges is adopted, which can better eliminate the error caused by the asymmetry of the body structure and improve the measurement accuracy . Specifically, there are two groups of four pressure-on-bit strain gauges 22, which are spaced 90° apart from each other. There are two groups of four torque strain gauges 23 , and the four torque strain gauges 23 are located at an angle of 45° between the two pressure-on-bit strain gauges 22 .

The four groups of patches are processed by bridge connection to eliminate mutual influence. As shown in Figure 5, the strain gauges in the same bridge arm direction are first connected in series, and then connected in series with the strain gauges in other bridge arm directions, and finally the strain gauges form a Wheatstone bridge structure inside all metal cylindrical grooves , this design can offset the influence of temperature changes on the measurement, and can also improve the measurement sensitivity. WOB on the left of Fig. 5 indicates the bridge connection form of the pressure-on-bit strain gauge, and TOB on the right indicates the bridge connection form of the torque strain gauge. The signals of the strain gauges on both sides pass through the first amplifier 40 and the second amplifier 42 respectively, and are collected into the filter. 30 and rectifier 32, and then output through digital output port 50.

The solution of the present invention can realize patching and calibration on the outside of the drill collar by setting an independent strain gauge embedding block. After the calibration is completed, it is assembled with the drill collar body by interference fit, which solves the ubiquitous problem of conventional downhole pressure-on-bit torque measurement. The patching process is complicated, and it is inconvenient to operate in the corresponding hole position on the drill collar, the position accuracy is poor, and the correction calculation is more complicated, etc., which has excellent popularization and application.

Although the specific implementation manner of the present invention has been described in detail in conjunction with the accompanying drawings, it should not be construed as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and deformations that can be made by those skilled in the art without creative efforts still belong to the protection scope of this patent.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Any simple modifications and equivalent changes made to the above embodiments according to the technical essence of the present invention all fall within the scope of the present invention. within the scope of protection.

Claims (10)

1. A downhole pressure-on-bit torque measurement system, characterized in that it includes a drill collar body (1), a strain gauge insert (2) and a sealing gland (3), and the surface of the drill collar body (1) is provided with a measurement groove, the sealing gland (3) press-fits the strain gauge embedded block (2) into the measurement groove in the form of interference fit; the strain gauge embedded block (2) includes the embedded block body (21), and is set The drill pressure strain gauge (22) and the torque strain gauge (23) on the block body (21), the upper end of the embedded block body (21) is in contact with the sealing gland (3), and the lower end is in contact with the drill collar body (1). 2. A downhole weight-on-bit torque measurement system according to claim 1, characterized in that, the embedded block body (21) includes two columns with different diameters, and the large-diameter column and the small-diameter column are the same. The shaft is connected as a boss structure. 3. A downhole weight-on-bit torque measurement system according to claim 2, characterized in that, the pressure-on-bit strain gauges (22) and torque strain gauges (23) are distributed on large-diameter cylindrical bodies and small-diameter cylindrical bodies to form on the step surface. 4. A downhole weight-on-bit torque measurement system according to claim 3, characterized in that, the pressure-on-bit strain gauges (22) and torque strain gauges (23) are evenly spaced circumferentially on the stepped surface , forming a strain gauge sensor array. 5. A downhole pressure-on-bit torque measurement system according to claim 2, characterized in that four measuring grooves are arranged on the same radial section surface of the drill collar body (1), and the four measuring grooves are evenly spaced. Distributed on the cross orientation of the radial section plane. 6 . The downhole weight-on-bit torque measurement system according to claim 5 , wherein the four sets of strain gauges corresponding to the four measurement grooves are connected by bridges to eliminate mutual influence. 6 . 7. The downhole weight-on-bit torque measurement system according to claim 1, characterized in that the material of the embedded block body (21) has a higher elastic coefficient than the material of the drill collar body (1). 8. A downhole pressure-on-bit torque measurement system according to claim 1, characterized in that, the sealing gland (3) is provided with a circlip (4) to limit its axial movement, and the sealing gland ( 3) The gap with the measuring tank is sealed with a sealing ring. 9. A downhole weight-on-bit torque measurement system according to claim 1, characterized in that it further comprises a battery pack (7) and a circuit (8) arranged inside the drill collar body (1) and connected to strain gauges, A battery board and a circuit (8) board are respectively arranged on the surface of the drill collar body (1) corresponding to the battery pack (7) and the circuit (8). 10. A downhole weight-on-bit torque measurement system according to claim 1 or 2, characterized in that, the bottom of the embedded block body (21) is provided with a positioning pin hole, and the bottom of the measuring groove is provided with a positioning pin shaft, and the The positioning pin hole cooperates with the positioning pin shaft to prevent the strain gauge insertion block (2) from rotating.

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