CN2682202Y

CN2682202Y - Two-wheel rolling centralizer for oil pipe

Info

Publication number: CN2682202Y
Application number: CNU032627785U
Authority: CN
Inventors: 刘凡
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-09-17
Filing date: 2003-09-17
Publication date: 2005-03-02
Anticipated expiration: 2013-09-17

Abstract

The utility model relates to a technique that a downhole instrument or a tool is centered in an oil pipeline in the production logging field of the oil exploration. Because two rolling wheels (8) are installed on a centering arm (7), and the minimum distance between the two wheels is longer than the distance between an upper pipe and a lower pipe at a pipe coupling point, the utility model can be coupled through the pipe. Because all sport components in the centralizer adopts sliding bearings to support evenly, the starting force is small, and the friction resistance is small, and the possibility that descending the well encounters resistance is reduced. The centering force reaches 200n-500n, and the centering force can be adjusted. The centering force can ensure the instrument dropped or the tool centered. The centralizer is used for the directional well or the horizontal well specially.

Description

A kind of two-wheel rolling centralizer of crossing oil pipe

Technical field

The utility model is a kind of downhole probe or instrument centralizer placed in the middle in petroleum pipeline that is used in oil exploration production logging field to make.

Background technology

Existing its operating principle of centralizer is that the elastic restoring force by arcuate bombing leaf makes downhole probe or instrument occupy the center of sleeve pipe 14, and instrument or the instrument gravity that relies on himself of going into the well glides.Usually the design of the elastic force of arcuate bombing leaf can not be too big, then makes the arcuate bombing leaf and the increase of wall friction power of centralizer too greatly, and causing goes into the well is hampered and arcuate bombing leaf wear damage very easily; As the elastic force that reduces arcuate bombing leaf then makes instrument poor to neutrality.Above-mentioned situation is particularly outstanding in directional well

Summary of the invention

Technical problem to be solved in the utility model provides a kind of big uprighting force, effective centralizer that reduces the frictional force of going into the well compared with prior art realized.Centralizer design scheme of the present utility model is as follows:

Described centralizer is referring to Fig. 1, mainly is divided into four groups by top connection 1, the center-pole 2 that runs through total length, upper spring 3, slide 6, eight righting arms 7 and forms by 90 ° of uniform arrangements of spaced radial, roller 8, lower spring 10, lower contact 11.Referring to Fig. 2, for the radial dimension that reduces centralizer and have that design has four pins and constitutes one with slide 6 on each slide 6 of sufficient intensity, be used to connect righting arm 7; Referring to Fig. 3, the aforementioned roller 8 same overall structures that adopt; The other end of righting arm 7 adopts pin 9 to connect and compose one group respectively; The minimum range that two scroll wheels 8 and two-wheeled be installed on every group of righting arm 7 is greater than the pipe box cupling place distance between the pipe up and down.The friction of itself and the borehole wall 14 when going into the well work of the centralizer of this utility model is changed into rolling friction by original sliding friction, and can be smoothly by the pipe box cupling referring to Fig. 4 (a) and (b), (c), (d); Because whole movement parts all adopts sliding bearing to be supported in the centralizer, starting power is little, frictional resistance is little, the possibility that having reduced goes into the well is hampered; Uprighting force reaches 200N～500N, can guarantee that downhole probe or worker are placed in the middle.Described centralizer is specially adapted in directional well or the horizontal well.

Description of drawings

Fig. 1 is a centralizer structure schematic diagram of the present utility model

Fig. 2 is that Fig. 1 is at the A-A sectional view of receiving the arm state

Fig. 3 is that Fig. 1 is at the B-B sectional view of receiving the arm state

Fig. 4 (a) and (b), (c), (d) are the schematic diagram of centralizer roller structure of the present utility model by pipe box cupling situation

The specific embodiment

Embodiment of the present utility model can be used for work in 2 3/8 " oil pipe to 8 5/8 " cased well for the centralizer of a kind of ￠ 43mm, normally use in pairs referring to centralizer shown in Figure 1, place the top of entrained instrument and bottom respectively, the top connection 1 of upper end centralizer is connected with logging cable Malong head, lower contact 11 is connected with instrument, leave therebetween run through line the hole referring to Fig. 2, Fig. 3; The top connection 1 of lower end centralizer is connected with the instrument tail, and center-pole 2 can make solid hopkinson bar, and the afterbody of lower contact 11 can make coniform being convenient to and go into the well.Upper spring 3 and lower spring 10 its physical dimensions are identical, respectively by about two spring revolving constitute, be used to overcome the torsional moment that spring itself produces when compressive strain.The endoporus of slide 6 studs with sliding bearing 13 and is enclosed within on the center-pole 2, and the hole at righting arm 7 two ends studs with sliding bearing 12 respectively.Slide 6 is provided with four uniform springs 4 and ejector pin 5, is used for effect initial torque thereon when righting arm 7 is regained fully, and assurance righting arm 7 is opened according to direction shown in Figure 1.The spacing of these embodiment two rollers 8 is designed to 40mm, 8 5/8 " screws in the tight back of machine at interval distance between the pipe up and down with setting of casing or oil pipe adopting box cupling to connect pipe up and down greater than what API Std (API SPEC 5CT) was recommended.

Claims

1. a two-wheel rolling centralizer of crossing oil pipe mainly is divided into four groups by top connection (1), the center-pole (2) that runs through total length, upper spring (3), slide (6), eight righting arms (7) and forms by 90 ° of uniform arrangements of spaced radial, roller (8), lower spring (10), lower contact (11); Its technical characterictic is gone up design for each slide (6) to be had four pins and constitutes one with slide (6), is used to connect righting arm (7); Aforementioned roller (8) adopts overall structure equally; The other end of righting arm 7 adopts pin (9) to connect and compose one group respectively; The minimum range that two scroll wheels (8) and two-wheeled be installed on every group of righting arm (7) is greater than the pipe box cupling place distance between the pipe up and down.