CN202903886U - Convenient and fast test probe for resistivity in well - Google Patents

Abstract

The utility model relates to a convenient and fast test probe for resistivity in well. The test probe comprises electrodes (1), an insulating cylinder (2), and a connecting cable (3), wherein four electrodes are respectively the first electrode (A), the second electrode (M), the third electrode (N), and the fourth electrode (A'), the four electrode (A, M, N, A') are mounted on the outer wall of the insulating cylinder (2) according to a certain spacing sequence and connected with a conduction wire in the connecting cable (3). Two ends of the power supply electrode are connected with a DC constant current power supply, the voltage across the two ends of the electrodes and the current are measured, so as to obtain the resistivity on the measurement point. The test probe for resistivity is reasonable in design, portable, high in test efficiency, and good in stability.

Description

Resistivity measurement probe in the simple and efficient well

Technical field

The utility model relates to the Geotechnical Engineering field tests, and more particularly it is resistivity measurement probe in a kind of simple and efficient well.

Background technology

In the engineering investigations such as water conservancy and hydropower, municipal works, road and bridge, for the resistivity (or conductivity) of obtaining Rock And Soil, need to carry out resistivity measurement in the well.

The resistivity measurement method generally adopts comprehensive logging instrument in the existing well, because this equipment need to be taken into account a variety of method of testings such as natural gamma, sound wave, well temperature, hole diameter, thus comparatively heavy, in alpine terrain complex condition difficult, affect testing efficiency.

Summary of the invention

The purpose of this utility model is to overcome the weak point of above-mentioned existing background technology, and the resistivity measurement probe is provided in a kind of simple and efficient well, it is aided with conventional, electric-resistance rate testing tool (measurement mechanism) can carry out resistivity in the well (or conductivity) test quickly and easily, this resistivity measurement probe designs is reasonable, and is light, efficient is higher, good stability.

The purpose of this utility model reaches by following measure: resistivity measurement probe in the simple and efficient well, it is characterized in that: comprise electrode, insulating cylinder, stube cable, described electrode has four, four electrodes are respectively the first electrode, the second electrode, third electrode, the 4th electrode, described four electrodes sequentially are contained in the outer wall of insulating cylinder according to certain spacing and are connected with wire in the stube cable.

In technique scheme, described four electrodes are symmetric offset spread, i.e. distance=third electrode between the first electrode and the second electrode and the distance=40cm between the 4th electrode, distance between the second electrode and the third electrode is 10cm, and the center of the distance between the second electrode and the third electrode is test 0 point.

In technique scheme, the fluid sealant insulated enclosure is adopted in the junction of described electrode and stube cable.

In technique scheme, described four electrodes adopt lead or the copper electrode that does not polarize.

Wire bonds in electrode in the utility model and the four-core stube cable is firm, power supply in measurement mechanism+with the power supply-two termination dc constant flowing powers, by the measurement in the measurement mechanism+and voltage, the electric current at measurement-two ends, can calculate the Rock And Soil resistivity that institute's location is put in the well according to following formula.

$\mathrm{\ρ}=\frac{4\mathrm{\π}\stackrel{\‾}{\mathrm{AM}}\·\stackrel{\‾}{\mathrm{AN}}}{\stackrel{\‾}{\mathrm{MN}}}\·\frac{{\mathrm{\ΔU}}_{\mathrm{MN}}}{I}=K\frac{{\mathrm{\ΔU}}_{\mathrm{MN}}}{I}$

In the formula: ρ is resistivity;

Be the distance between electrode A and the electrode M;

Be the distance between electrode A and the electrode N;

Be the distance between electrode M and the electrode N; Δ U _MNBe the voltage between electrode M and the N; I is the electric current between electrode M and the N; K is electrode coefficient.

The present invention adopts four electrodes, and wherein when the AB power supply, MN is measured as first group of data, and when A ' B power supply, MN is measured as second group of data, adopts two groups of data to carry out resolution and Rock And Soil layering precision that analysis-by-synthesis is conducive to improve resistivity measurement in the well.The applicable boring aperture scope of the utility model is 50～150mm.

Description of drawings

Fig. 1 is structural representation of the present utility model.

Fig. 2 is the structural representation during resistivity measurement in the simple and efficient well of the utility model.

Among the figure: 1. electrode, 2. insulating cylinder, 3. stube cable, 4. measurement mechanism (resistivity measurement instrument), A. the first electrode, M. the second electrode, N. third electrode, A '. the 4th electrode,

. the distance between the first electrode and the second electrode, . the distance between third electrode and the 4th electrode,

. the distance between the second electrode and the third electrode.

Embodiment

Describe performance of the present utility model in detail below in conjunction with accompanying drawing, but they do not consist of to restriction of the present utility model, only for example, simultaneously by illustrating that advantage of the present utility model will become more clear and understands easily.

Consult accompanying drawing as can be known: resistivity measurement probe in the simple and efficient well of the utility model, comprise electrode 1, insulating cylinder 2, stube cable 3, described electrode 1 has four, four electrodes are respectively the first electrode A, the second electrode M, third electrode N, the 4th electrode A ', described four electrode A, M, N, A ' sequentially are contained in the outer wall of insulating cylinder 2 and are connected (as shown in Figure 1) with wire in the stube cable 3 according to certain spacing.

Described four electrode A, M, N, A ' are symmetric offset spread, i.e. distance between the first electrode and the second electrode

Distance between=third electrode and the 4th electrode

=40cm, the distance between the second electrode and the third electrode

Spacing is 10cm, and central point is for testing zero point between the second electrode and the third electrode.Described electrode 1 adopts fluid sealant insulation perfusion sealing (preventing electric leakage) with the junction of stube cable 3.Described four electrode A, M, N, A ' adopt lead or the copper electrode that does not polarize.

In the test process, power supply two termination dc constant flowing powers in the measurement mechanism, the positive source of wherein powering+connect, the power cathode of powering-connect, power simultaneously-be placed on away from wellhole position and ground connection, the electrode A in the probe connect power supply+, electrode M and N connect respectively measurement+and measure-(the perhaps electrode A in the probe ' connect power supply+, electrode M and N connect respectively measurement-and measure+), the electric current at potential electrode MN two ends and voltage can calculate the resistivity value of measurement point.

Other unaccounted part is prior art.

Claims (3)

1. resistivity measurement is popped one's head in the simple and efficient well, it is characterized in that: comprise electrode (1), insulating cylinder (2), stube cable (3), described electrode (1) has four, four electrodes are respectively the first electrode (A), the second electrode (M), third electrode (N), the 4th electrode (A '), described four electrodes (A, M, N, A ') sequentially are contained in the outer wall of insulating cylinder (2) according to certain spacing and are connected with wire in the stube cable (3); Described four electrodes (A, M, N, A ') are symmetric offset spread, i.e. distance between the first electrode and the second electrode

Distance between third electrode and the 4th electrode

Distance between the second electrode and the third electrode

Spacing is 10cm, the distance between the second electrode and the third electrode

The center for the test 0 point.

2. resistivity measurement probe in the simple and efficient well according to claim 1 is characterized in that the fluid sealant insulated enclosure is adopted in the junction of described electrode (1) and stube cable (3).

3. resistivity measurement probe in the simple and efficient well according to claim 2 is characterized in that lead or the copper electrode of described four electrodes (A, M, N, A ') for not polarizing.

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