ALMAZ-2T complex

Almaz2 Sm

ALMAZ-2 complex was put into production in February 2002, the complex being essentially updated as compared with ALMAZ-1.

The ALMAZ-2 independent complex is designed for geophysical research of the inclined wells, open boreholes and wells with horizontal completion, including lateral boreholes of 124...144 mm diameter, being drilled for oil and gas. The Complex is delivered downhole on the drilling tool and allows to measure and to record the following parameters during one trip:

  • apparent resistivity using 9 induction logging tools for different depths;
  • natural wellbore polarization potential (WP);
  • azimuth, inclination (zenith) angle and whipstock orientation angle (angle of tool rotation);
  • natural formations gamma-ray activity (Gamma);
  • drilling mud resistivity (R);
  • drilling mud temperature;
  • hydrogen porosity using 2NNK-T method.

The ALMAZ-2 complex independent wellbore system is delivered downhole by the drilling tool. This way of delivery provides an ability to log the extended horizontal sections of the wellbores being surveyed.


Complex consists of:

Complex structure and performance

The ALMAZ-2 complex operating principle is based on the simultaneous recording of two data sets: downhole, and at the surface. Using MPP the wellbore complex records parameters measured by VEMKZ (9 induction logging tools phase difference and WP potential), and also real-time-linked information from MGKR (drilling mud resistivity, drilling mud temperature). Similarly, the inclinometer data (inclination angle, azimuth, angle of rotation) is recorded by the inclinometer module MIA, «hydrogen» and «neutron» porosity (NP) and integral natural rock radioactivity (Gamma) are recorded by the compensated neutron-neutron logging module MARK.

The Surface tying to depth system measures and records the downhole modules location depth, also linked to time. Then the special program matches two data files, one from the downhole and the other from the surface, by the time parameter using interpolation. As the result of program performance, the time parameter becomes excluded and tying to depth file of parameters is created.

Structurally VEMKZ, MGKR, MPP, MARK, MIA modules are joined between each other with the connection joints of the same type. The modules are mechanically fixed by trapezoidal thread sleeve nut. The connection joint is made of titanium, that provides high corrosive and abrasive resistance.

Electrical connection of modules is achieved through the sealed connectors, which in the emergency situations withstand hydrostatic pressure up to 100 MPa, that would extend the complex life if one of the modules is depressurized.

General specifications of complex

Max. hydrostatic pressure, MPa 60
Operating temperature range, °C for:  
downhole modules +10...+85
using Li batteries MWD140CC up to +125
depth control system -40...+40
Max. diameter, mm 102
Total length of borehole modules with reducing pipe, m 14.46
Total weight of borehole modules with reducing pipe, kg 315
Permissible vibroimpact loads according to Russia State Standard 26116-84 group MC2-3
Min. curvature radius of a borehole, m 60
Permissible axial load:  
max. compression load, ton 10
max. breaking load, ton 30
Max. speed of logging run, m/h 1000
within kickoff interval, m/h 200
Max. logging speed, m/h 720
Max. time of complex operation with whole load, h 8
Max. internal discrepancy between the clock of MPP and that of Interface block for 24 hour, s 1
Supply voltage of downhole modules, V from 12 to 17
Extreme conditions for transportation:  
ambient air temperature, °C −50...+50
ambient air relative humidity at 30 °C, % 90

Weight and dimensions specifications of the complex modules

Designation Length, mm Width, mm Height, mm Diameter, mm Length for the
Weight, kg

Specifications of VEMKZ module

The number of channels for measurement for:  
phase difference by induction probes 9
SP 1
Measurement range of resistivity, Ohm.m 1-200
The main measurement error, %,
where pa is measured value of apparent resistivity,
pu is the upper limit of measurement range.
Maximum consumption current, A 0.7
Overall dimensions, m:  
diameter 0.102
max. length 3.8
VEMKZ module weight, kg 80
Measurement ranges:  
for induction probes (phase shift), deg ± 90
for SP, V ± 1.25
Measurement discontinuity:  
for induction probes (phase shift), deg. 90/4096
for SP, mV 2500/4096
Transition time after the device is turned on, s. 5

Specifications of Memory and power module MPP

Mpp Sm

Memory and power module (MPP) provides downhole measuring modules with power, records measured parameters with link to real time, and measures shock loads.

Accumulator block voltage (8 CYCLON accumulators), V 16
Max. drop in accumulator block voltage
(at the moment of maximum current drain), V
Min. battery block capacity, A/h 25
Nonvolatile memory volume, Mb 4
Max. relative clock drift per 24 h, s 1
Self average power consumption, W 0,3
Length, m 2.38
Weight, kg 75

Specifications of integral GK module and resistivity measuring module MGKR

Mgkr Sm
Measured parameters:
  • Integral gamma-ray activity of rocks
  • Drilling mud resistivity
  • Drilling mud temperature
Measurement range of natural
gamma-ray activity of rocks, mR/h
Measurement range of drilling
mud resistivity, Ohm.m
from 0.02 to 10
Max. relative error of resistivity measurement, % 5
Measurement range of drilling
mud temperature, °C
from +5 to +85
Max. relative error of temperature
measurement, °C
Max. consumption current, A 0.3
Length, m 1.82
Weight, kg 35

Independent resistivity meter and thermometer measurement module MART

Mart Sm

It contains built-in battery and memory module. It is designed for measuring drilling mud resistivity in the extended range (from 0.02 to 20 Ohmm). The thermometer graduation is 0.005 degree C.

Radioactivity logging independent module MARK

Nnk1 Sm

Radioactivity logging wellbore independent module (MARK) is designed for evaluating rock «neutron» porosity using compensated neutron-neutron logging by thermal neutrons (2NNKT) method.

MARK consists of:
  • small logging tool NNKT of 280 mm length,
  • large logging tool NNKT of 530 mm length,
  • Gamma-detector with crystal NaJ(Tl) 30x150, and FEU190,
  • Memory and power module (MPP).

Fast neutron source: plutonium beryllic IBN 8-5 with the outlet of 1-107 n/sec. The photo shows the connection joint with a slot for the neutron source.

The MARK operating principle is in the rock radiation processing by the fast neutrons (up to 12 MeV) and registering the neutrons that slowed down to thermal energy. For this purpose in the tool structure there are two arrays of the thermal neutron He3-detectors, located at different distances from the source. In the formations with the great number of hydrogen atoms, even at the short distance from the source, neutrons slow down to thermal energies and are merged effectively. Therefore, small logging tool to large one detector counting rates ratio is maximal. This ratio decreases when the tool is against the formation with the minimal hydrogen concentration, and the neutron slow-down length is maximal. While calibrating the tool in the model environments, that have different water-saturated porosity, one can obtain analytical dependence of the tool data from actual porosity of the rock being investigated.

Nnk2 Sm

The length of the tool is 2.15 m, the diameter is 0.102 m, the weight is 46 kg. The Figure shows the module's general view.

The tool gets power from the built-in nickel-cadmium battery, which has enough capacity to work continuously during 18 hrs. The tool software is integrated into RealDepth software package.

The module have successfully passed downhole tests, and was accepted for serial production.

Maharay Sm

Depth control system

Surface tying to depth system is used for measuring hoisting block movement, and hook weight. Under RealDepth program control an «effective» drilling tool movement linked to current time is calculated.

Specifications of depth control system

PLP converter of linear displacements:

Min. measurement range of displacements, m 30
Step of displacement, mm 5
Overall dimensions, m 0.4*0.3*0.2
Max. weight, kg 10
Min. tension of measuring cable, N 10

Cable tension converter (PNT):

Max. tension measurement range, ton 5
Max. overall dimensions, m 0.37*0.13*0.13
Max. weight, kg 5

Interface block:

Max. supply voltage, V 220 ± 22
Max. total power consumption, W 120
Max. real time of clock drift per 12 h, s 1
Max. overall dimensions, m 0.25*0.20*0.08
Max. weight, kg 1.5

Specifications of service blocks

Monitor unit

Supply voltage, V 220 ± 22
Max. total power consumption, W 30
Max. overall dimensions, m 0.25*0.20*0.08
Weight, kg 1.5
Ambient air temperature, °C +10...+45


Supply voltage, V 220 ± 40
Max. total power consumption, W 150
Charging current strength, A 5
Nominal output voltage, V from 14 to 24
Max. overall dimensions, m 0.25*0.20*0.08
Weight, kg 2
Ambient air temperature, °C +10...+45

RealDepth software system

Realdepth Sm
Is developed for controlling program modules:
  • borehole complex hardware modules processors,
  • geophysical data processors,
  • metrological assurance processors.

It provides all the ALMAZ-2T modules with controlling, programming, testing, calibrating functions, supports tying to depth system operating, allows reading information from MPP, tying it to depth, and outputing data in the form of standard LAS-files.