You are here

Standard electric logging tool ESK


The tool has the following modifications by max operating temperature T max and upper value of borehole hydrostatic pressure Pmax :
  by temperature: 120, 150, 175, 200 °С,
  by pressure: 80, 100, 120, 140 МPа.

Designed to measure apparent resistivity (ρa) of the rocks crossed by a borehole using methods of conventional logging (CL), resistivity measurement, self-polarization potential (SP) and SP gradient (ΔSP).

Used in the open oil and gas holes filled with water-base mud; the tool operates with a three-conductor carrying logging cable up to 7000m long and log recorders that provide for command transfer and data receipt in “Manchester-2” code. 

 reservoir identification in oil and gas wells section;
 formation resistivity evaluation;
 reservoir saturation evaluation.

The measuring equipment contains five electrodes placed on a hard electrically insulated housing. Electrode switching and power supply arrangement provides for ρa measurement by standard lateral sondes A2M0.5N and N0.5M2A, normal sonde A0.5M2N, resistivity measurement and also SP and ΔSP.

 Measured parameters Range Error
ρa А2.0M0.5N 0÷1000 Ohm·m ± (5+20/ρa)%
ρa N0.5M2.0A 0÷1000 Ohm·m
ρaА0.5M2.0N 0÷200 Ohm·m
Resistivity meter 0.2÷200 Ohm·m
М∞N(SP) from +1.25 to -1.25 V ±1 mV
М∞N (ΔSP) from +100 to -100 mV ±1 mV

 General specifications
Tool length, mm 7000 not more than
Tool diameter, mm 76 not more than
Tool weight, kg 80 not more than
Power supply:
supply voltage, V
supply frequency, Hz


Borehole diameter, mm 110÷350  
Logging speed, m/hr up to 2000  
Combinability feed-through  
Location in the borehole free