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Research methods.
The paper uses standard methods and devices such as IR spectroscopy,
viscomemetry, methods for the study of hardness, adhesion, tribotechnical properties of dispersed
systems, and also used experimental, field-observational and generally accepted hydraulic methods,
drawing up mathematical models based on hydromechanics laws, together with Topics,
mathematical statistical methods in the processing of experimental data.
Results and discussion.
The weak link in the mining and chemical industry, for
hydrotransport of dispersed systems, up to 90% of the total number of damage to which is
accounted for by corrosion. Due to the use of recently hermetically isolated on the side of the
structures, the duration of the trouble-free operation of the hydrotransport of dispersed systems is
determined by corrosion of the inner surface and the pumping of the steel pipe pumps. The
calculation of the values of the corrosion rate of such sites will allow them to estimate their service
term of the τ
t
year, in order to predict planned repairs by equation
"Modern Materials Science: Topical Issues, Achievements and Innovations" (ISCMMSTIAI-2022)
357
𝜏
𝑡
=
(𝑆
𝑜𝑟𝑔
+𝑆
𝑠
)
𝐾𝑤
𝑙
(1)
where S
org
and S
s
—
Accordingly, the thickness of the pipe wall on the sortiment and calculated
according to the strength characteristics, mm (at present, when determining the
S
s
value, the supply
of corrosion is not provided); K - the speed of the internal corrosion of the pipe, mm / year; W, -
local corrosion factor, dimensionless value. To date, an important task is to create a calculated
methodology for estimating the intensity of corrosion of hydrotransport of dispersed systems, taking
into account the characteristics of the metal of heat lines, water-chemical, hydrodynamic and
temperature coolant temperature. The complexity of solving this problem is explained by a plurality
of parameters affecting a corrosion process, a large zone of their uncertainty associated with a
significant length of heat transport systems, fluctuation of the concentration of chemical corrosion
reagents, electric currents, chemical composition of pipe material, etc.
Earlier [13-14] presents the mechanisms of internal corrosion in hydrotransport dispersed
systems and the output of the formula, according to its speed. The calculation gives the parameter
value to several times lower than in real conditions of operation of the hydrotransport, probably due
to lower solubility values of the C
m
, kg/m
3
, magnetite obtained in laboratory conditions, and
violations of the water-chemical mode in dispersed systems. Moreover, this difference increased
significantly with an increase in the inner diameter of d
i
of hydrotransport.
To increase their performance, one of the methods is a modification of dispersed systems
with low-molecular organic compounds. As a modifier, the State Phase resin is chosen by
secondary raw materials of little fat production. Polyphenols, fatty acids, hydrocarbons,
nitrogen and phosphorus-containing compounds, as well as the transformation products of the
State Psycho, are present in the composition of the State Person. Its appearance is visco -fluid
mass, color - from a dark brown to the black, acid number of KOH - 50-100 mg, the ash content
is 1.0-1.2 wt.%, moisture content and volatile substances - up to 4-6%, solubility in acetone-70-
80 wt.%, Specific weight 3-0.98-0.99 g/cm, The number of coeximensions of KOH - 80-130
mg [2,5,7].
The work was used by the State Pharmaceutical resin of oil and waged complexes, obtained
by distillation of fatty acids at a temperature of 220-2300c, containing in its composition from 40
to 50% of condensation products, polymerization and state-line interaction products. Modified
dispersed systems formed in the Metallurgical Combine 1% gosypol resin. To do this, in the model
(1) it is proposed to enter the function q (d
i
).
Therefore, in this paper, a refined method of calculating the internal corrosion of the pipes of
hydrotransports made from carbon steel grade 20 is also proposed. Also, for the convenience of
calculations on the PС in the procedure under consideration, the approximating functions of C
q
(t,
pH) of the solubility of magnetite from the temperature f and hydrogen indicator pH are integrable
dispersed systems, as well as its density ρ(t) and viscosity µ(t). Considering the above, the rate of
internal corrosion can be assessed by the following formula:
К =
𝛽𝑞
р
с
𝜃 𝐶
𝑢
1
𝑘
+(1−𝜒)(
ℎ
𝐷
+
1
ℎ𝐷
)
(2)
where β —
coefficient recalculation m/s in mm/year; q - coefficient depending on the parameter
d
i
;
р
s
, - density of steel arising on the inner surface, kg/ m
3
; θ- porosity of the dense layer of magnetite,
pipes, shares; k is the rate of corrosion reaction at the metal - oxide border, m/s; χ is the proportion
of magnetite in corrosion products (χ = 0,5 for the normalized oxygen concentration in the heating
system); h is the thickness of the dense layer of magnetite, m (taken according to the results of a
survey of specific areas of hydrotransports, on average h - 1 10-5 m);
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