CN1023871C

CN1023871C - Diameter-regulating centralizing device

Info

Publication number: CN1023871C
Application number: CN 91104148
Authority: CN
Inventors: 帅健; 于永南; 吕英民; 蔡强康
Original assignee: PETROLEUM UNIV
Current assignee: PETROLEUM UNIV
Priority date: 1991-06-26
Filing date: 1991-06-26
Publication date: 1994-02-23
Anticipated expiration: 2006-06-26
Also published as: CN1055979A

Abstract

The present invention relates to a well drilling centralizer which can be used for the exploitation of petroleum and other mines, particularly to a near-bit centralizer which is used for the directional drilling and the horizontal drilling. The centralizer comprises a centralizer body, centralizing blocks and a sleeve, wherein the sleeve is connected with the centralizer body through a bearing in a rotary way, the sleeve is provided with at least three centralizing blocks, and at least one plate spring is installed on the sleeve among the centralizing blocks and the sleeve. The centralizer has the advantages of simple structure, convenient manufacture, low manufacture cost, small abrasion, large diameter adjusting range and good centralizing effect, can be used for the condition of expanded well bores, and is particularly suitable for the directional drilling operation and the horizontal drilling operation.

Description

Diameter-regulating centralizing device

The centralizer that uses when the present invention relates to drilling centralizer, especially near-bit centralizer, particularly directed drilling that oil and other mining activities use and horizontal drilling.

The centralizer of prior art, of a great variety, by its purposes branch, be casing stabbing board, drilling centralizer, the centralizer of logging equipment, early stage have a US3237696, US3282349, US3289768, US3343608, US3292705, US3356147, US3977468, US3978924 is disclosed to install the centralizer that a flexible outer wear-resisting lath is set upright on body;

Above centralizer, it is bad to set upright effect, is not suitable for setting upright of drilling well tubing string, and especially directed drilling and horizontal drilling tubing string sets upright.

SU827748 discloses a kind of centralizer, several wear-resisting circles are set on this centralizer to be rolled, and these circle rollers are supported on the centralizer body by a flexible member, SU145851 discloses a similar centralizer, this centralizer, complex structure, for relatively little borehole space, the structure that the round roller of macro-energy impact is born in arrangement is difficult, its flexible member can only play a part to absorb impact, may come hardly to adjust the radial dimension of centralizer to adapt to its variation according to the size variation of well size.

In the drilling process, because the variation of formation condition, hole diameter is changing, and the change of hole diameter needs centralizer can adapt to it, only in this way, could play real centralizing function, especially when directed drilling and horizontal drilling, centralizer can not adapt to the well condition of enlarged well, will cause the bigger deviation of directed drilling or horizontal drilling direction, even causes the drilling well failure.

The objective of the invention is to overcome the deficiencies in the prior art, and provide a kind of simple in structure, easy to use, can adapt to the centralizer of path transfer automatically that well enlarges situation.

Diameter-regulating centralizing device of the present invention comprises centralizer body, wiper block, and sleeve, sleeve is connected with centralizer body rotationally by bearing.Have at least three bar grooves on the sleeve, in each bar groove wiper block is housed, have angle in the bar groove of sleeve, between wiper block and the sleeve leaf spring is housed, leaf spring in each bar groove is two groups, the balanced wiper block that supports of leaf spring, and two ends of leaf spring insert in the above-mentioned angle.Centralizer body can connect with drill bit or drill collar routine, and promptly two ends are shaped on corresponding connection screw thread.

Centralizer of the present invention, simple in structure, easily manufactured, cheap, centralizer wearing and tearing are minimum, and the path transfer scope is big, can adapt to the hole diameter condition of enlarged, sets upright effectively, is particularly useful for directed drilling and horizontal drilling operation.

For introducing the present invention in detail, describe below in conjunction with accompanying drawing:

Fig. 1 is the sectional structure schematic diagram of centralizer of the present invention;

Fig. 2 be among Fig. 1 A-A to the sectional structure schematic diagram;

Fig. 3 is the schematic diagram of another embodiment of centralizer of the present invention.

Referring to Fig. 1, Fig. 2, this diameter-regulating centralizing device, comprise centralizer body 1, wiper block 5 also comprises a sleeve 4, sleeve 4 is connected with centralizer body 1 rotationally by bearing 3, have at least three bar grooves 42 on the sleeve 4, in each bar groove 42 wiper block 5 is housed, at least one leaf spring 6 is housed between wiper block 5 and the sleeve 4.

Centralizer body 1 wherein can connect with drill bit or drill collar routine, and promptly two ends are shaped on corresponding connection screw thread, not shown in the drawings these structures.

Bearing 3 wherein preferably adopts thrust bearing, and by the connection of bearing 3, the sleeve 4 of centralizer and wiper block 5 can not rotate with the rotation of drill collar in drilling process, can significantly reduce the wearing and tearing of wiper block 5 like this, prolong its application life.

Above-mentioned wiper block 5 is 3 to 8, decides according to the size of centralizer, for the centralizer of large-size, the wiper block of a greater number can be set.

Above-mentioned wiper block 5 can be made the section configuration with " T " font, and its external surface is a circular arc, and to play centralizing function better, two ends of wiper block 5 suitably produce inclined-plane 51, reduces the friction with the borehole wall.

Above-mentioned leaf spring 6 can freely be placed in the bar groove 42 on the sleeve 4, also can in the bar groove 42 on the sleeve 4, produce two or four or more a plurality of angle 41, two ends of leaf spring 6 insert in this angle 41, and leaf spring 6 can obtain relative location like this, specifically referring to Fig. 3.

Above-mentioned leaf spring 6 can be the leaf spring of monolithic, also can be the lamination leaf spring more than two or two, the pressure-bearing leaf spring on the similar automobile chassis.

No matter be single-leaf spring, also no matter be laminated spring, no matter also leaf spring 6 is in the bar groove 42 that freely is placed on the sleeve 4, still detachably two ends of leaf spring 6 are inserted in the angle 41 of bar groove 42, said leaf spring 6 can be two groups, promptly respectively adorns one group at two ends of wiper block 5, can also be more than two groups, especially for long centralizer, organize leaf spring more and can support wiper block 5 equably.

For guaranteeing that whole centralizer can work well in drilling process, at two ends of sleeve 4 seal cover 2 is housed, prevent from mainly that drilling cuttings from entering to destroy its operate as normal in the bearing 3.

Because wiper block 5 is supported on the leaf spring 6,, reduce the impact that centralizer body 1 is subjected to so this centralizer can absorb vibration and impact energy.

Claims

1, a kind of diameter-regulating centralizing device, comprise centralizer body, wiper block, sleeve, sleeve is connected with centralizer body rotationally by bearing, have at least three bar grooves on the sleeve, in each bar groove wiper block is housed, it is characterized in that: have angle in the bar groove of sleeve, between wiper block and the sleeve leaf spring is housed, leaf spring in each bar groove is two groups, the balanced wiper block that supports of leaf spring, and two ends of leaf spring insert in the above-mentioned angle.

2, diameter-regulating centralizing device according to claim 1 is characterized in that above-mentioned leaf spring is the leaf spring of monolithic.

3, diameter-regulating centralizing device according to claim 1 is characterized in that above-mentioned leaf spring is the lamination leaf spring more than two or two.