CN203515369U

CN203515369U - Bow-spring elastic centralizer

Info

Publication number: CN203515369U
Application number: CN201320671460.8U
Authority: CN
Inventors: 魏宪章
Original assignee: DAQING BAOXIN JINRUI MACHINERY EQUIPMENT Co Ltd
Current assignee: DAQING BAOXIN JINRUI MACHINERY EQUIPMENT Co Ltd
Priority date: 2013-10-29
Filing date: 2013-10-29
Publication date: 2014-04-02
Anticipated expiration: 2023-10-29

Abstract

A bow-spring elastic centralizer is mainly composed of rigid centralizing frames and elastic centralizing strips. The bow-spring elastic centralizer is characterized in that the rigid centralizing frames include an upper rigid centralizing frame and a lower rigid centralizing frame, a sliding sleeve is inserted between the upper and lower rigid centralizing frames, sliding flanges are designed at two ends of the sliding sleeve, the outer diameter of each sliding flange is in sliding contact with the inner circumference of the corresponding rigid centralizing frame, positioning rings are arranged on inner diameters of two ends of the two rigid centralizing frames, and the elastic centralizing strips are connected between the two rigid centralizing frames. The bow-spring elastic centralizer has the advantages that due to the design of the sliding sleeve, the whole centralizer is firm and reliable, centralizing pieces do not fall off, the bow-spring elastic centralizer is suitable for vertical wells and particularly suitable for well cementation of inclined wells, horizontal wells and small-gap wells, the two rigid centralizing frames can limit offcenter of the sleeve to the utmost extent, the elastic centralizing strips can automatically adjust centralizing force in the process of sliding in an axial limiting range, better centralizing effect is guaranteed, and the sleeve is enabled to be centralized as much as possible.

Description

Bow spring elastic centralizer

technical field:

The utility model relates to mechanical equipment technical field, refers in particular to a kind of bow spring elastic centralizer.

background technology:

In the well shaft fixing technology process of all kinds of drilling engineerings such as at present domestic and international oil, natural gas, salt industry, underground heat and ore deposit, ground, conventionally require to keep casing centralization, the cement paste injecting while making to cement the well can improve displacement efficiency, replace the most up hill and dale drilling fluid, and be evenly distributed in the annular space between casing string and the borehole wall, guarantee cementing quality.The general method adopting is on casing string, to add centralizer.Conventional centralizer has two classes at present, one class is category of rigid brace type centralizer, rigid centralizer has more definite restriction to the bias of sleeve pipe, but the restriction that is often subject to upper strata casing inner diameter and drill bit borehole diameter due to the maximum outside diameter of rigid centralizer is difficult to abundant amplification, be difficult to make casing string placed in the middle to greatest extent, especially in unconsolidated formation well section and hole diameter well bigger than normal, righting strip is easy to embed stratum or centralizer together with casing string whole departure well axis, produce larger bias, for the sealing quality that improves annular space displacement efficiency and cement sheath, usually be difficult to see Expected Results, and, rigid centralizer does not possess elastic centralizer semielliptic spring steel disc peculiar " ski " effect, in setting of casing process, force of sliding friction between the righting strip that it is hard and stratum or upper strata sleeve pipe is huge, have a strong impact on casing safety and be successfully lowered into predetermined well depth, further creeping into operation to bottom or completion practice brings very large difficulty, another kind of is elastic type centralizer, be commonly called as spring centralizer or lantern centralizer, can coordinate preferably with borehole size, there is stronger compliance, especially when facing particularity stratum undergauge or borehole wall corrosion, well collapses when spoiling hole diameter and occurring more seriously expanding, its righting effect placed in the middle or expansion stream flow-disturbing raising displacement efficiency is fairly obvious, but when hole angle is remarkable, lateral force obviously increases, especially in high angle hole and horizontal well, the righting effect placed in the middle of simple elastic type centralizer just seems very limited.

summary of the invention:

The purpose of this utility model is to provide a kind of bow spring elastic centralizer, overcomes the deficiency of simple use rigid centralizer or elastic centralizer.

The purpose of this utility model realizes as follows: a kind of bow spring elastic centralizer, mainly by rigidity righting frame and elasticity righting strip, formed, it is characterized in that: described rigidity righting frame is divided into upper and lower two, in the middle of upper and lower two rigidity righting frames, be plugged with sliding sleeve, at sliding sleeve two ends, be designed with slip flange, all footpaths sliding-contact in slip flange external diameter and rigidity righting frame, on the two ends internal diameter of two rigidity righting frames, be provided with locating ring, described elasticity righting strip is connected in the middle of two rigidity righting frames.

The beneficial effects of the utility model are, because the design of sliding sleeve makes whole firm reliable, body resistance-strengthening tablets does not come off, be not only applicable to straight well, be also particularly suitable for the well cementation of inclined shaft, horizontal well and little gap well, limiting boot is eccentric to greatest extent for two rigidity righting frames, elasticity righting strip is vertically in limited range in sliding process, automatically regulate uprighting force, guarantee better righting effect, make sleeve pipe as much as possible placed in the middle.

accompanying drawing explanation:

Accompanying drawing 1 is the utility model structural representation.

In Fig. 1: locating ring 1, rigidity righting frame 2, sliding sleeve 3, elasticity righting strip 4.

the specific embodiment:

With reference to accompanying drawing 1, a kind of bow spring elastic centralizer, mainly by rigidity righting frame 2 and elasticity righting strip 4, formed, it is characterized in that: described rigidity righting frame 2 is divided into upper and lower two, in the middle of upper and lower two rigidity righting frames 2, be plugged with sliding sleeve 3, at sliding sleeve 3 two ends, be designed with slip flange, slip flange external diameter and the interior all footpaths sliding-contact of rigidity righting frame 2, on the two ends internal diameter of two rigidity righting frames 2, be provided with locating ring 1, described elasticity righting strip 4 is connected in the middle of two rigidity righting frames 2.

Claims

1. one kind is bent spring elastic centralizer, mainly by rigidity righting frame (2) and elasticity righting strip (4), formed, it is characterized in that: described rigidity righting frame (2) is divided into upper and lower two, in the middle of upper and lower two rigidity righting frames (2), be plugged with sliding sleeve (3), at sliding sleeve (3) two ends, be designed with slip flange, all footpaths sliding-contact in slip flange external diameter and rigidity righting frame (2), on the two ends internal diameter of two rigidity righting frames (2), be provided with locating ring (1), described elasticity righting strip (4) is connected in the middle of two rigidity righting frames (2).