CN105672915A - Outer-diameter-variable cutting bed removing tool - Google Patents

Abstract

The invention discloses a debris bed removal tool with variable outer diameter, which comprises an upper joint, a cylindrical body and a lower joint arranged in sequence from top to bottom, and a knife groove is arranged on the outer surface of the cylindrical body , an axially fixed and radially movable scraper is embedded in the sipe, a bow spring is arranged between the scraper and the bottom surface of the sipe, the scraper is supported by the bow spring, and the bow The upper and lower ends of the spring are fixed on the bottom surface of the knife groove. The invention adopts the structure that the bow spring supports the scraper in the radial direction, and the outer diameter of the scraper can change with the size of the borehole during the process of lifting the drilling tool, so that the outer diameter of the tool can change with the size of the borehole. When reaching the build-up section or irregular wellbore, the outer diameter of the cuttings bed removal tool can be changed with the change of the wellbore size, which can effectively reduce the risk of tripping and blocking, and at the same time increase the service life.

Description

A Variable Outer Diameter Debris Bed Removal Tool

technical field

The invention relates to the technical field of drilling engineering, in particular to a cuttings bed removal tool with a variable outer diameter during the drilling of highly deviated wells.

Background technique

As an effective means to develop marginal oilfields at low cost, highly deviated wells have become one of the most widely used well types in oilfields at home and abroad. However, the problem of wellbore cleaning in highly deviated wells is a recognized problem in the industry. The accumulation of cuttings beds will induce various downhole complex situations and even accidents, and traditional wellbore cleaning methods and methods cannot effectively solve this problem, which seriously restricts Improve drilling efficiency. Using the cuttings bed removal tool while drilling can effectively and quickly remove the cuttings bed, keep the borehole clean and improve work efficiency. Some problems that still exist are that the size of the traditional cuttings bed remover is slightly larger than the size of the drill pipe while drilling, which increases the risk of tripping and blocking while cleaning the wellbore; at the same time, through statistical analysis of field application conditions, tool wear Seriously, the entire tool will be unusable after the tool is partially worn, and the economic benefit is low. According to the actual situation and conditions of the site, the development of a more suitable cuttings bed removal tool will effectively improve the operating efficiency.

Contents of the invention

The present invention provides a cuttings bed removal tool with variable outer diameter to solve the technical problems existing in the known technology. life.

The technical solution adopted by the present invention to solve the technical problems in the known technology is: a cuttings bed removal tool with variable outer diameter, including an upper joint, a cylindrical body and a lower joint arranged in sequence from top to bottom. The outer surface of the cylindrical body is provided with a knife groove, and an axially fixed and radially movable scraper is embedded in the knife groove, and a bow spring is arranged between the scraper and the bottom surface of the knife groove , the scraper is supported by the bow spring, and the upper and lower ends of the bow spring are fixed on the bottom surface of the knife groove.

The scraper adopts a PDC composite blade, and the PDC composite blade is inlaid on the blade body of the scraper.

The scraper is a spiral scraper.

The maximum gap between the scraper and the bottom surface of the sipe is 25.4 mm.

The advantages and positive effects of the present invention are: the outer diameter of the scraper can be changed with the size of the wellbore during the lifting and lowering process of the drilling tool by using the structure of the bow spring to support the scraper in the radial direction, so that the outer diameter of the tool can be adjusted As the borehole size changes, the outer diameter of the cuttings bed removal tool can change with the borehole size when encountering a build-up section or an irregular borehole, which can effectively reduce the risk of tripping resistance and improve the use of life. The invention adopts a spiral scraper, which has a strong guiding effect on the incoming flow, and can effectively increase the return speed of the drilling fluid in the annular space; at the same time, when the tool rotates while drilling, the degree of fluid turbulence in the annular space will increase, causing cuttings to Evenly distributed in the annulus, it can effectively prevent the formation of the cuttings bed, so that the cuttings can be efficiently transported back to the wellhead in the large annulus above the drilling tool. The PDC composite blade is inlaid on the spiral scraper, which can effectively improve the efficiency of cutting the cuttings bed and the service life of the tool.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the structural representation that scraper of the present invention and bow spring are installed in the knife groove;

FIG. 3 is a sectional view along line A-A of FIG. 1 .

In the figure: 1, upper joint, 2, scraper, 3, cylindrical body, 4, bow spring, 5, lower joint.

detailed description

In order to further understand the invention content, characteristics and effects of the present invention, the following examples are given, and detailed descriptions are as follows in conjunction with the accompanying drawings:

Please refer to Figures 1 to 3, a variable outer diameter cuttings bed removal tool, including an upper joint 1, a cylindrical body 3 and a lower joint 5 arranged in sequence from top to bottom, on the cylindrical body 3 A knife groove is arranged on the outer surface of the knife groove, and an axially fixed and radially movable scraper 2 is embedded in the knife groove, and a bow spring 4 is arranged between the scraper blade 2 and the bottom surface of the knife groove. The scraper 2 is supported by the bow spring 4, and the upper and lower ends of the bow spring 4 are fixed on the bottom surface of the knife groove.

In this embodiment, the scraper 2 adopts a PDC composite blade, and the PDC composite blade is inlaid on the blade body of the scraper 2, and some scrapers can be replaced after being damaged. Described scraper 2 adopts the helical scraper used on the traditional cuttings bed remover. The maximum gap between the scraper 2 and the bottom surface of the knife groove is 25.4mm.

Working principle of the present invention:

Run the tool while drilling. As the drilling tool rotates, the scraper cuts the cuttings bed downhole. At the same time, due to the large cross-sectional area of the cuttings bed removal tool, the surrounding flow rate is significantly increased. The rotation of the drilling tool increases the degree of turbulence of the drilling fluid in the annular space and achieves a better cleaning effect of the cuttings bed. At the same time, during the tripping process of the drilling tool, when encountering a build-up section or an irregular borehole, the outer diameter of the cuttings bed removal tool can change with the size of the borehole, which can effectively reduce the The friction resistance reduces the risk of encountering resistance when tripping and descending.

Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific implementations. The above-mentioned specific implementations are only illustrative and not restrictive. Those skilled in the art Under the enlightenment of the present invention, people can also make many forms without departing from the purpose of the present invention and the scope of protection of the claims, and these all belong to the protection scope of the present invention.

Claims (4)

1. A variable outer diameter cuttings bed removal tool, characterized in that it comprises an upper joint, a cylindrical body and a lower joint arranged in sequence from top to bottom, and the outer surface of the cylindrical body is provided with A knife groove, in which an axially fixed and radially movable scraper is embedded, a bow spring is arranged between the scraper and the bottom surface of the knife groove, and the scraper is supported by the bow spring, so The upper and lower ends of the bow spring are fixed on the bottom surface of the knife groove. 2 . The variable outer diameter cuttings bed removal tool according to claim 1 , wherein the scraper adopts a PDC composite blade, and the PDC composite blade is inlaid on a cutter body of the scraper. 3 . 3. The variable outer diameter debris bed removal tool according to claim 1 or 2, characterized in that the scraper is a spiral scraper. 4. The variable outer diameter debris bed removal tool of claim 1, wherein the maximum clearance between the scraper and the bottom surface of the sipe is 25.4 mm.