Decision by Expert Technical Council at State Commission on Mineral Resources
Recommend the inclusion of the combined steady-state nuclear LWD tool (made by OOO NPP Energiya, LLC) in the register of technologies approved by Expert Technical Council at State Commission on Mineral Resources.


Geophysical equipment

Geophysical instrumentation manufactured by RPE Energiya, LLC (ООО «НПП Энергия»)

Key element


Neutron tubes developed by RPE Energiya, LLC (ООО «НПП Энергия») and FSUE Integrated Plant “Electrohimpribor” (ФГУП «Комбинат «Электрохимприбор»)


Self-contained neutron-neutron logging tool APNNK-90


Designed to carry out geological well logging using the method of compensated three-probe neutron-neutron logging of thermal neutrons 2NNKt (2ННКт) and gamma-ray logging of geological material natural activity using one independent detector unit (gamma-ray logging).

Designed to explore very pitching and horizontal sections of oil- and gas-well bores filled with oil- and water based circulation fluid with NaCl content up to 300 g/l.

Active tasks:

  • correlation of well logs and lithologic changes;
  • detailed lithologic differentiation;
  • stratigraphic studies;
  • determination of gas-bearing formations, gas-liquid and oil-water contact;
  • determination of gas saturation factor.

Tool is designed to operate with a plutonium-beryllium neutron source, type IBN-8-5 (ИБН-8-5) with neutron flux between 5×106 and 2×107 s-1. Neutron detector units – helium counter tubes. Gamma-quantum detector scintillation crystal with a photo-electronic multiplier.


Measured parameters Range Accuracy
Natural gamma-ray EDR of geological materials 0÷250 μR/h 15 %
Porosity measurement range 0÷40 % 4.2+2.3(40/ КA-1) %
Gamma-ray logging channel sensitivity at least 750 pulses/min per 1 μR/h


General technical specifications
Tool overall length, mm 3720 max.
Tool diameter, mm 90 max.
Total tool weight, kg 110 max.
Maximum ambient temperature, °C 90 (120) see Note 
Maximum hydrostatic pressure, MPa 80  
Logging speed, m/h 800  
Diameter of the hole, mm от 120 до 350  
Standalone downtime, hours in recording mode 10  
Record frequency, (samples per second) 2  
Sitting on drill tool  

Note: during logging in wells with temperature over +90ºC it is necessary to use either special heat-resisting power supply elements or thermostat control device for rechargeable battery pack.