CN201071713Y

CN201071713Y - Down-hole vertical poly-magnetic probe

Info

Publication number: CN201071713Y
Application number: CNU2007200325333U
Authority: CN
Inventors: 张国辉; 詹保平; 李彦民
Original assignee: XI'AN WELL-SUN ELECTRONIC INSTRUMENT Co Ltd
Current assignee: Xi'an Well-sun Electronic Instrument Co., Ltd.
Priority date: 2007-08-16
Filing date: 2007-08-16
Publication date: 2008-06-11
Anticipated expiration: 2017-08-16

Abstract

The utility model provides a down-hole vertical magnetism gathering probe provided with a polar plate assembly and two main transmitting coils. The two transmitting coils adopt differential enwinding. A pair of auxiliary magnetism gathering coils are arranged on the inner side of the two transmitting coils, outside of which two reflection shielding layers are arranged. The polar plate assembly is composed of eight polar plates and each polar plate includes eight receiving coils. The total 64 receiving coils are arranged in an alternative way. Each polar plate is embedded with a signal amplifier, which can accurately identify the damage (wall thickness) of down-hole casing pipe wall at any position, overcome measuring errors caused by the current electromagnetic vortex thickness gauge probe and effectively enhance the measuring precision, thus serving as an ideal probe in the electromagnetic vortex field.

Description

Down-hole vertical magnetic probe

Technical field

The utility model relates to magnetic calibrator field, is specifically related to a kind of probe of downhole electromagnetic eddy current thickness meter.

Background technology

At present, the oil field generally acknowledges that the probe of best electromagnetic eddy current thickness meter is the used probe of being produced by Britain SONDEX company of magnetic calibrator (MAGNETIC THICKNEES TOOLS MTT001).Fig. 5 is exactly the probe of the MTT-001 magnetic calibrator of Sondex company production.It receives only coil 12 by a transmitting

coil

5 and 12 and forms, 12 receive only coil is 30 degree angles distributions in one plane, because measuring method requirement, this plane must be placed on the far-field region of transmitting coil, because must there be certain distance in the far-field region to receiving transducer, so the useful signal that receiving coil can receive is very little, has only the microvolt level, under the effect of various interfering signals (volt level), cause big measure error sometimes.Other two receive only between the coil (between the 30 degree angles) does not have receiving coil to survey whether sleeve pipe damages and the test leakage that causes instrument, so can give to measure yet and explain and cause test leakage.

Summary of the invention

In order to overcome the measure error that existing electromagnetic eddy thickness meter probe causes, the utility model provides a kind of efficient down-hole vertical magnetic probe, it can be discerned the down-hole casing wall exactly and appoint damage state based (wall thickness) that closes the position, improves the certainty of measurement of magnetic calibrator effectively.

The technical scheme that realizes the utility model purpose is a kind of down-hole vertical magnetic probe, probe comprises pole plate assembly and two main transmitting coils, be provided with a pair of attached poly-magnetic coil that helps two main transmitting coil inboards, the pole plate assembly is arranged on telescoping ram, two main transmitting coil skins are provided with three layers of shielding, screen layer is by innermost copper lamina, middle aluminium thin layer, and outmost permalloy layer is formed; The pole plate assembly is made up of eight pole plates, is equipped with eight on every pole plate and receives only coil, has 64 and receives only coil, and receiving coil is arranged by the array interleave; Eight pole plates are when opening, and per two angles that receive only between the coil are 5.625 degree; Be provided with signal amplifier in pole plate, signal amplifier is made up of amplifier block, circuit galley and high magnetic conduction supporting plate, and signal amplifier is encapsulated in the same pole plate with the detection receiving coil.

Down-hole vertical magnetic probe is a kind of new departure in magnetic calibrator field, its applied method both added the distance that increases between transmitting coil and the receiving coil unlike the far-field eddy method in order to overcome the direct-coupled influence in magnetic field, also requiring to receive pole plate unlike the current vortex leakage method must closely contact with casing wall.It is the special construction that utilizes transmitting coil and receiving coil, change the number and the arrangement of coil, develop electromagnetism Thicknesser probe near perfect condition, as can be seen from Figure 2, casing wall is passed in the magnetic field that two main transmitting coils send, and concentrates on to receive near the pole plate and vertically pass receiving coil to turn back to main transmitting coil again.Like this, we just can utilize the variation of detected signal amplitude of receiving coil and phase place, accurately reflect the variation of casing wall thickness.

The utility model can effectively improve certainty of measurement, verifies in actual measurement: certainty of measurement can improve more than 80%.Because or else the increase (have on every pole plate of eight pole plates eight receiving coils are arranged) of receiving coil quantity can produce in the application to appoint and close test leakage, casing wall is taken up an official post close the breakage at position can both be detected out and can clearly be reflected on the image in addition.

Description of drawings

Fig. 1 is the probe schematic diagram of the electromagnetic thickness tool of down-hole perfect condition.

Fig. 2 is the structural representation of down-hole vertical magnetic probe.

Fig. 3 is the frame for movement schematic diagram of down-hole vertical magnetic probe.

Fig. 4 is pole plate (the comprising signal amplifier) structural representation of down-hole vertical magnetic probe.

Fig. 5 is the sonde configuration schematic diagram of the MTT-001 magnetic calibrator of Britain Sondex company production.

Fig. 6 is that the pole plate receiving coil array interleave of down-hole vertical magnetic probe is arranged schematic diagram.

Fig. 7 is the pole plate receiving coil and the signal amplifier circuit connection diagram of down-hole vertical magnetic probe.

The specific embodiment

Before the narration technical scheme, the guiding theory of design is described earlier: the probe of optimal in theory downhole electromagnetic eddy current thickness meter should be as shown in Figure 1: transmitting probe is outside casing wall, receiving coil is in casing wall, tube wall is vertically passed in the magnetic field of transmitting probe emission, the signal amplitude that receives of receiving coil can be directly proportional with the thickness of casing wall like this, in fact transmitting probe is to be put into the casing wall outside, the present invention makes the approaching desirable probe state of down-hole vertical magnetic probe of design by the following technical solutions.

As shown in Figure 2, down-hole vertical magnetic probe mainly is made up of four parts: main coil screen layer 1, attached poly-magnetic coil 2, pole plate assembly 3, the main transmitting coil 5 of helping.Two main transmitting coils 5 adopt the differential method coilings, the magnetic field that makes its emission near pole plate assembly 3 because of the mutually exclusive focussing force that produces; Add the attached effect that helps the magnetic resistance magnetic field of poly-magnetic coil 2 generations, the magnetic line of force 6 that forces main transmitting coil to produce vertically passes casing wall 4, the useful signal that pole plate receiving coil 12 receives is produced by the magnetic line of force 6 that vertically passes casing wall 4, and the variation of its amplitude and phase place can accurately reflect the variation of casing wall thickness.

As shown in Figure 3, pole plate assembly 3 is made up of eight pole plates 7, has eight to receive only coil 12 on every pole plate, and after telescoping ram 8 was pushed open, 64 receive only coil may detect the take up an official post varied in thickness of unification point of sleeve pipe circumference.

As shown in Figure 4, signal amplifier is made up of amplifier block 9, circuit galley 10 and high magnetic conduction supporting plate 11.The input amplifier of circuit is encapsulated in the same pole plate 7 with detection receiving coil 12.As shown in Figure 7, L1-L8 is that eight of a pole plate receives only coil, and A-H is eight road amplifiers, MAX398 eight selects a converter, because line is very short between receiving coil 12 and the input amplifier, so reduced the interference of small-signal transmission course effectively, has effectively improved certainty of measurement.

Creativeness of the present utility model mainly shows following several respects:

(1) probe adopts two transmitting coils and 64 to receive only coil:

After adopting two transmitting coils, because transmitting coil 5 adopts differential coiling, make magnetic field form magnetic focusing near receiving coil, the useful signal that receives improves 3 to 4 times than with transmitting power single transmit coil the time, has improved certainty of measurement thereby put.Receiving coil is increased to 64 from 12, and receiving coil 12 is arranged by the array interleave, as shown in Figure 3, eight pole plates are when opening, 64 coils are two planar alignment on the pole plate, as shown in Figure 6, eight on every pole plate receives only coil and comes on two planes first plane and second plane.Distance is 5 centimetres between two planes, and use formula: B=K X F/S can obtain the umber of pulse of delay, wherein B: the pulse number of delay; K: be the pole plate constant; F: instrument operating frequency (hertz); S: test the speed (rice/hour).When two row's receiving coils were at a distance of 5 centimetres on the pole plate, pole plate K value was 180.After delay was handled through following formula, a plane was synthesized on two planes, and 64 receive only coil working on same circumference.Two angles that receive only coil have only 5.625 degree, and when whenever receiving only the coil investigative range when spending greater than 6, probe just can guarantee not have test leakage in 360 degree scopes.

(2) increase the attached poly-magnetic coil that helps:

From Fig. 2, can see, increase a pair of attached poly-magnetic coil 2 that helps near two transmitting coil inboards.Its significant feature is: produce the vertical toroidal magnetic field of a circle in casing wall 4, because this magnetic direction is vertical with the magnetic field of main transmitting coil, the magnetic field that main transmitting coil is launched can not be prolonged casing wall fully and be flowed, but after passing casing wall 4 earlier, near receiving coil, vertically return in the sleeve pipe again.

(3) outer the increasing of main transmitting coil shields:

Transmitting coil 5 is core components of down-hole vertical magnetic probe, increase two-layer reflection shield 1 outside transmitting coil, layer of copper approaches (0.3mm), and layer of aluminum approaches (0.3mm), outermost increases one deck and absorbs screen layer (permalloy 0.2mm), and the main coil emission effciency is improved.

(4) employing has the source plates scheme:

Because the signal that receiving coil 12 receives is very little, in long Distance Transmission process, can receive and disturb and produce measure error, thus signal amplifier is put in the pole plate 7, small-signal is exaggerated after transmission again, can improve signal to noise ratio effectively like this, improve certainty of measurement.

Claims

1. down-hole vertical magnetic probe, it is characterized in that on telescoping ram (8), being provided with pole plate assembly (3) and two main transmitting coils (5), two main transmitting coils (5) adopt differential coiling, be provided with a pair of attached poly-magnetic coil (2) that helps in two main transmitting coils (5) inboard, outside two main transmitting coils (5), be provided with screen layer (1), pole plate assembly (3) is made up of eight pole plates (7), has eight to receive only coil (12) on every pole plate, is provided with signal amplifier in pole plate (7).

2. down-hole vertical magnetic probe as claimed in claim 1 is characterized in that receiving coil (12) has 64, and receiving coil (12) is arranged by the array interleave.

3. down-hole vertical magnetic probe as claimed in claim 1 is characterized in that screen layer (1) by innermost copper lamina, middle aluminium thin layer, and outmost permalloy layer is formed.

4. down-hole vertical magnetic probe as claimed in claim 1, it is characterized in that described signal amplifier is made up of amplifier block (9), circuit galley (10) and high magnetic conduction supporting plate (11), signal amplifier and receiving coil (12) are encapsulated in the same pole plate (7).

5. down-hole vertical magnetic probe as claimed in claim 1 is characterized in that eight pole plates when opening, and per two angles that receive only between the coil (12) are 5.625 degree.