The installation and replacement of radiation source are
accomplished with the help of underwater lighting and long-
handled tools under the water.
At present,
the world's total power of radiation source
of cobalt used in industry for irradiation reaches approximately
one megawatt (100 million curies).
Table of Characteristics of -Ray Radiation Sources
Item
Kind of ray
Cobalt-60
य
Caesium-137
Ч
Energy
1.17, 1.33 MeV
0.66 MeV
Radioactive half-life
5.27 years
30.2 years
Specific activity
Self-absorption
50-100 curie/g
10 %
24 curie/g
30-50 %
Radiation intensity
required per KW
67,000 curie
300,000 curie
2.
Shielding-protection system
Usually concrete or lead shieldings are employed.
That is,
concrete or lead is used to build the shielded irradiation
room in which a water well is dug with radiation source stored
The task for irradiating the products is accomplished
therein.
in the said irradiation room.
3. Conveying system for the products being irradiated
In an industrial irradiation apparatus, the inletting of
products into the irradiation room or the outletting of the
irradiated products therefrom is completed by means of an
automatically controlled conveying system.
2
The Translation Division of Tai Dao Publishing Ltc