NEW TYPES OF WELL RESLSTIVITY -METERS 



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Fig. 6. The well resistivity- 

 meter of the type RCE-3-57. 



the electrode device the latter is placed away 

 from the teriniiiations for a distance approxi- 

 mately equal to three diameters of the container. 



The upper part of the cap (4) has an affixed 

 standard cable head, while the lower cap (5) is 

 connected to the probe by a special joint. The 

 resistivity-meter caps have channels through 

 Avhich — as well as through the median brass 

 tube — passes the central straird of the cable. 



In the resistivity -meter RSE-3-57 the elec- 

 trode N again has a three dimensional shape 

 and encloses the electrodes A and M, which 

 are near to each other. As a result the measuring 

 device of this resistivity -meter does not, in prin- 

 ciple, differ from the arrangement 8, although 

 superficially they appear to be very different. 



In order to avoid dirtying the resistivity -meter 

 by grease aird to simplify the circulation of the 

 drilling fluid near the electrode device all the 

 parts of both resistivity-meters are streamlined 

 and any corners which may preclude the motion 

 of the drilling fluid have been eliminated. To 

 stabilize the influence of the metallic parts of 

 the resistivity-meter oil the probe the con- 

 tainers and the terminal parts of the instruments 

 are made of stainless steel, and all the instru- 

 mental parts are nickel plated to decrease sticking 

 of clay particles. The resistivity -meters RSE-3-57 

 and REU-57 can be used as independent in- 

 struments in the existing logging installations, 

 as well as parts of complex bore-hole devices. 



In certain cases it is necessary to alter the 

 terminal parts of their bodies. 



Figure 1 shows the results of determining 

 the coefficient of REU-57 in fluids of different 

 specific resistance. It is clear that the REU-57 

 resistivity -meter coefficient changes much less 

 than the coefficients of the existing resistivity- 

 meters. With the increase in the specific resis- 

 tance of the fluid from 0.1 to 30 the REU-57 



