VEGA VEGASOURCE 31 - Manual (Page 15)

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3 Product description
VEGASOURCE 31 •
38131-EN-130415
3.2 Principle of operation
The VEGASOURCE 31 is a source holder for shielding radioactive
sources such as Cs-137 or Co-60.
The radioactive source in the source container emits gamma rays.
The VEGASOURCE 31 is mounted on the vessel or the pipeline
directly opposite the sensor.
The source container shields the environment against gamma radia-
tion and protects the radioactive source against mechanical damage
or chemical influences. In case of large measuring ranges (e.g. with
high vessels) two or more source containers are used.
The VEGASOURCE 31 consists of the following components.
1
2
3
4
Fig. 9: Source container VEGASOURCE 31
1 Source container
2 Changeover/Locking facility
3 Transport lug
4 Connection flange
The rays emitted by the gamma source are damped when penetrat-
ing the medium. The sensor detecting the attenuated radiation on the
opposite side of the vessel calculates the measured value from the
intensity of the radiation.
The following table states the max. activity of the sources. Production-
related fluctuations of the source activity and tolerances of the meas-
uring instruments are not taken into account.
Co-60 Cs-137
Max. activity max. 0.74 GBq (20 mCi) max. 22.2 GBq (600 mCi)
Tab. 2: Max. activity of the sources
Co-60 Cs-137
Attenuation factor 37 294
Number of the half-value layers 5.2 8.2
Application area
Functional principle
Source