Page 7 - Dys_Usov 2021

7

operation has been investigated and a decrease in the amount of perlite from 35 to
30% has been proved. The surface of the anode after 20.5 years of operation is

subjected to general and peptic corrosion, the depth of ulcers will be up to 1 mm
outside the pipe and up to 0.7 mm on the inner surface. It is confirmed that

hardness of metal is not a value sensitive to operational degradation.
Electrochemical studies have shown that the resistance of the soil and the

resistance of anode grounding from steel 20, after a long period of operation, is

gradually increasing. It is established that the potential of corrosion and the anode

current of dissolving steel 20 of the stock tube and the anode practically coincide.

However, the exploited steel is inherent in a slightly higher intensity of anode

dissolution in the potential of -0.40 V, this indicates the advantage of the use of

anodes from pre-exploited pipes against the reservoir tubes due to economic and

functional expediency.
The study of the characteristics of the anode grounds of steel 12Х18Н10Т,

which showed that in 2.5 years of operation, the metal structure has not changed

and satisfies the current requirements of GOST 550-75. An increase in the strength

of the anode grounds of steel 12Х18Н10Т is shown by 3–8% and not significant

corrosion processes.

Eleotrochemical studies of the anode grounds of steel 12Х18Н10Т showed

improvement of corrosion deficiency in exploited steels, but over time, this may

lead to an increase in electrical resistance in the anode-coke filling system, which

will cause increased operational and energy expenses.

The studies of steel anode grounding from steel 20 have shown that the

anode earthing switches in their physical condition can continue to operate as

anode grounding, but simultaneously established an increase in electrical resistance

in the system of anode-soil from 2 to 20-40 ohms.

To reduce the electrical resistance of the anode grounds of steel 20, active

substances (activators) were laid. After exploitation of the anode ground with

activators for 23 months, a spectral analysis of anodic grounding samples was

performed that the chemical composition of the steel has not changed and fully