CN102094584A

CN102094584A - Double-acting type drill stem stabilizing device

Info

Publication number: CN102094584A
Application number: CN2009102626112A
Authority: CN
Inventors: 牛子久
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-12-14
Filing date: 2009-12-14
Publication date: 2011-06-15

Abstract

The invention discloses a double-acting type drill stem stabilizing device used in the field of petroleum drilling. The double-acting type drill stem stabilizing device comprises an axle body, at least two fixed sleeves and at least one movable sleeve, wherein the axle body penetrates through the fixed sleeves and the movable sleeve, the fixed sleeves are fixed on the axle body absolutely, and the movable sleeve is fixed on the axle body relatively. When the double-acting type drill stem stabilizing device rotates with a drill stem in a well, the fixed sleeves fixed on the axle body absolutely can trim the shrunken well; when the axle body is tend to be pushed away from the center of the well by a radial force, the movable sleeve presses the wall of the well along with the axle; however, the movable sleeve is fixed on the axle body relatively and can rotate around the axle body, therefore, the coefficient of friction between the movable sleeve and the axle body is smaller than that between the movable sleeve and the wall of the well; as the radial pressure is equal, the movable sleeve cannot be driven to scrape the wall of the well by enough force, the wall of the well corresponding to the movable sleeve is not scraped, and the diameter of the well is not changed at a size after scraping of the fixed sleeves; at the same time, the axle body is restrained by the wall of the well through the movable sleeve so as to enable the center of the fixed sleeves fixed on the axle body absolutely not to offset the center of the well, thus over-scrape of the wall of the well, caused by the fixed sleeves, can be prevented.

Description

Double-acting type drill stem stabilization device

Technical field

The present invention relates to be used to make the drill string stability-of-path in the oil drilling industry, prevent the device of well off-design index, especially can the scraping borehole wall can prevent the drill stem stabilization device of the undue scraping borehole wall again.

Background technology

In the oil drilling industry, drill bit and drilling rod are necessary equipments, because the external diameter of drill bit is greater than the external diameter of drilling rod, make the well of drill bit process greater than the drilling rod external diameter, an annular space is arranged between the just whole drill string and the borehole wall, this provides necessary ways for circulating fluid, has also produced the hidden danger at drill string misalignment well center simultaneously inevitably.Placed in the middle in order to guarantee drill string, many places are connected in series some stabilizers on drill bit usually, and the outer wall of stabilizer is uniform-distribution with the stable bar of several projections, and the external diameter of stablizing bar is slightly less than borehole diameter.The circumferential surface of stablizing bar is close on the borehole wall, under the effect of huge axial compression, comprises that the drill string of stabilizer can occur bending and deformation, along with distortion, axial compression is partly decomposed radially, and along with rotation, radial load makes to be stablized bar and press to the borehole wall and continue the scraping borehole wall.For the bigger stratum of hardness, it is bigger to stablize the bar rate of wear, and the senior general that adds who stablizes bar and borehole wall distance significantly reduces the performance of stabilizer; For the less stratum of hardness, the scraping action meeting of stablizing bar enlarges borehole diameter, can significantly reduce the performance of stabilizer thus equally, therefore stablize the design that bar and stabilizer rotate simultaneously with integral form and can not have satisfied the drilling well requirement of raising day by day.

Dynamically contact problems such as the frictional resistance that causes is big, stabilization efficiency is low in order to solve the monolithic stabilizer with the borehole wall, utility model patent drilling tool centralizer (97232786.X) discloses a kind of oil drilling drilling tool centralizer, this utility model is by having increased a centralizer body between the axle and the borehole wall, changed the formation of friction pair, become metal to metal by the metal pair borehole wall.Say from point of view of tribology merely, the sure reduction spin friction of this design resistance, but angle from drilling technology, there is a defective in this design, because in the Process of Oil Well Drilling, the borehole wall is subjected to the drilling fluid immersion can take place that de-stabilise expands and well is shunk, if centralizer body does not have scraping function and external diameter constant, when borehole diameter diminishes, will cause the axial rub resistance to strengthen and on put and put the drilling tool difficulty.

Summary of the invention

The problem that exists at above-mentioned technology the present invention proposes a kind of double-acting type drill stem stabilization device, and it can not only the scraping borehole wall when stablize drill string, repairs well, can also prevent the undue scraping borehole wall.

The object of the present invention is achieved like this: having on the axis body of axially extending bore, fixing at least two fixed covers and at least one moving cover, deciding cover and definitely be fixed in axis body, moving cover relative fixed is in axis body, and can not be broken away from axis body but decide the cover restriction around the axis body rotation.When the present invention in well during with drill string rotating, definitely be fixed in the well that cover can be repaired contraction of deciding of axis body, when radial load occurring axis body pushed away the trend at well center, moving cover is also pressed to the borehole wall thereupon, but moving cover is that relative fixed is in axis body, can be around the axis body rotation, moving cover to the friction factor of axis body less than the friction factor of moving cover to the borehole wall, under the identical condition of radial pressure, there is not enough strength to order about the moving cover scraping borehole wall, the corresponding borehole wall of moving cover is not subjected to scraping, its borehole diameter maintains the size constancy of deciding after the cover scraping, and at this moment, axis body is subjected to the constraint of the borehole wall by moving cover, make and definitely be fixed on deciding the cover center and can not depart from the well center on the axis body, thereby the undue scraping borehole wall is overlapped in anti-fastening.

Description of drawings

Fig. 1 is the longitudinal sectional view of first embodiment of the invention.

Fig. 2 be part 2 partly cut open sectional view.

Fig. 3 is the right view of Fig. 2.

Fig. 4 be part 3 partly cut open sectional view.

Fig. 5 is the right view of Fig. 4.

Fig. 6 is the longitudinal sectional view of second embodiment of the invention.

The specific embodiment

The invention will be further described below in conjunction with the drawings and specific embodiments.

As shown in Figure 1, on the axis body 1 that has through hole, be installed with and decide cover 2, moving cover 3 and overlap 4 surely, surely overlap 2 and overlap 4 surely and can not rotate on axis body 1 and can not endwisely slip, promptly definitely fixing, moving cover 3 can rotate on axis body 1, but be limited in deciding cover 2 and overlap surely between 4, be i.e. relative fixed.

Surely overlapping 2 and overlap 4 fixed form surely and be not limited to a kind ofly, can be that the fixing or standard fasteners of welding is fixed.

Second embodiment as shown in Figure 6 on axis body 1, has increased by one and has overlapped 5 and moving covers 6 surely.

The above is not whole embodiment of the present invention; by changing shape and compound mode; those skilled in the art can also amplify out a lot of embodiment, can also prevent that the technical characterictic of the undue scraping borehole wall is all in protection domain of the present invention so long as use when the mode of moving fixed combination is provided with the body realization scraping borehole wall.

Claims

1. double-acting type drill stem stabilization device is characterized in that: described stabilising arrangement is made of axis body, two fixed covers and at least one moving cover at least.Axis body passes decides cover and moving cover, decides cover and definitely is fixed in axis body, and moving cover relative fixed is in axis body.