Page 22 - НАЦІОНАЛЬНА АКАДЕМІЯ НАУК УКРАЇНИ

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on corrosion resistance of stainless steel is positive, but it can cause problem in the
analysis of the effectiveness of cathodic protection. Therefore, their use will require a
larger number of anode tubes as a result of a decrease in current output, but will provide a
long service life due its high resistance to pitting.
During the operation of anode groundings, a significant problem is the gradual
increase in electrical resistance in the anode-soil system. A significant, from 2 to 21 Ohm,
increase in electrical resistance in the anode steel 20-soil system after ~ 20 years of
grounding operation is shown, which reduces the effectiveness of the cathodic protection
of the pipeline.

A new method has been developed to improve the efficiency of anode grounding
from steel pipes using activators, which made it possible to reduce and stabilize the
resistance of the anode-soil system. Using activators such as NaCl, NH₄NO₃ and mixture
+
+
2+
-
2+
of the content: 32,4% (Na + K ), 19,2% (Са + Мg ), 8,4% NH₄ , 17,8% Cl , a rest –
+
2-
СО , when applied over 23 months, the electrical resistance of the 20 steel anode
3
decreased by 56, 30 and 20%, and soil resistance – by 58, 58 і 53%, correspondingly
compared to the anode without an activator. Activators have no effect on the corrosion
potential of the 20 steel, and its corrosion resistance after operation as an anode with a
NaCl activator is lower by ~ 20% compared to an anode without an activator.
A new design of anode grounding on the basis of a steel pipe has been developed,
which provides the ability to controllably reduce the resistance in the anode-soil system
by periodic pounding of 5000 liters of technical solution or water. The developed design
of the anode grounding provides the possibility to fill in the liquid inside the pipe at
increasing the electrical resistance of the anode, and the cut holes allow the liquid to seep
to the outer surface of the pipe and reduce the electrical resistance in the anode-soil
system by 35-50%. It has been shown by practice that placing active substances near the
anode groundings is technically simple and economically viable method, which enable to
extend the service life of operated anode groundings.
Key words: steel, active substances, anode grounding, electrical resistance,
cathodic protection, corrosion.