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LABORATORY EXPERIMENT № 11

STUDY OF THE STRUCTURE OF DOWNHOLE PRESSURE
GAGES. DECODING THE DIAGRAMS WRITTEN WHILE

MEASURING BOTTOM HOLE AND FORMATION
PRESSURE. TECHNOLOGY AND TECHNIQUE FOR
CARRYING OUT THE DOWNHOLE MEASUREMENTS

11.1 The objective of the experiment is: to study the structure
of downhole pressure gage (downhole pressure gage of helix type
DPGNS-2 (МГН-2)), to get skills in decoding the diagrams recorded

during the measurements of bottom hole and formation pressure and
to study the technology and technique for carrying out the downhole

measurements.

11.2 Definitions

11.2.1 The application of downhole pressure gages and their types

Bottom hole and formation pressure in oil or gas well is measured

by means of downhole pressure gages.
Downhole pressure gages are the main devices at well and
formation researches. They are used for:
1) measurement of the absolute magnitude of the pressure on the well

bottom;
2) measurement of the formation pressure;
3) determining the difference between two magnitudes of bottom hole

pressure (depression);
4) measurement of the bore hole pressure;
5) measuring the increase of pressure (difference between the initial

and current magnitude of bottom hole pressure) depending on the test
time.
By the principle mof operation the downhole pressure gages
are divided into the following types:

1. Spring (helix) downhole pressure gages. In these downhole
pressure gages helix spring (multicoil hollow tube spring) is
the sensitive element. Downhole pressure gages of this type are the

following devices: DPGNS-2 (МГН-2), DPGT-1 (МГТ-1), DPGFT-1M

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