Method for predicting service life of zinc strip

Abstract

The invention provides a method for predicting the service life of a zinc strip, and the method comprises the following steps: determining the service life of a to-be-predicted zinc strip according to the minimum section diameter, the corrosion allowance coefficient and the corrosion rate of the to-be-predicted zinc strip. According to the method for predicting the service life of the zinc strip, determination is carried out according to the minimum section diameter, the corrosion allowance coefficient and the corrosion rate of the to-be-predicted zinc strip, the physical or chemical parameters directly reflect the corrosion behavior and performance change of the zinc strip in a specific environment, errors caused by a single factor are avoided, and therefore the prediction accuracy is high.

Description

Technical Field

[0001] The invention belongs to the technical field of equipment life prediction, and in particular relates to a method for predicting the life of a zinc strip. Background Art

[0002] With the development of the national economy, urban infrastructure construction continues to expand, with increasing numbers of high-voltage / ultra-high-voltage AC transmission lines, high-speed railways (including conventional electrified railways), and oil and gas pipelines being built on a large scale. Due to geographical constraints, the parallel or intersecting installation of oil and gas pipelines with high-voltage / ultra-high-voltage AC transmission lines and high-speed railways (including conventional electrified railways) is becoming increasingly common. AC interference, caused by AC electric fields or AC stray currents, is becoming increasingly common in oil and gas pipelines. In recent years, an increasing number of pipelines have suffered corrosion, perforation, and leakage due to AC interference, and an increasing number of pipeline bodies and their accessories have been damaged by AC currents from faults. According to national standards such as GB / T40377-2021 "Corrosion of Metals and Alloys—Determination and Protection Guidelines for AC Corrosion," GB / T50698 "Technical Standard for AC Interference Protection of Buried Steel Pipelines," and SY / T0087.6 "Standard for Corrosion Evaluation of Steel Pipelines and Storage Tanks—Part 6: AC Interference Corrosion Evaluation of Buried Steel Pipelines," AC protection measures are required to mitigate the risk of pipeline AC interference when the pipeline AC interference risk is assessed as medium or high.

[0003] Zinc strip grounding is the most common measure for AC interference protection. However, under the influence of AC current, the zinc strip itself will also suffer AC corrosion. Over time, the zinc strip will gradually wear out and even corrode and fracture, thus losing its ability to mitigate AC interference. Therefore, accurately predicting the service life of zinc strips under AC interference and replacing them in a timely manner are crucial to ensure the safety of pipelines, ancillary facilities, and pipeline management personnel. Summary of the Invention

[0004] The main purpose of the present invention is to provide a method for predicting the service life of a zinc strip, which can accurately predict the service life of the zinc strip under AC interference.

[0005] The present invention provides a method for predicting the life of a zinc strip, comprising the following steps:

[0006] The service life of the zinc strip to be predicted is determined according to the minimum cross-sectional diameter, corrosion allowance coefficient and corrosion rate of the zinc strip to be predicted.

[0007] The method as described above further includes: determining the corrosion rate of the zinc strip to be predicted based on the surface area, density, AC current flowing through the surface, relative atomic mass of zinc, number of electrons of zinc ions, and AC current efficiency of the zinc strip to be predicted.

[0008] The method as described above further includes: determining the surface area of ​​the zinc strip to be predicted based on the minimum cross-sectional diameter, the maximum cross-sectional diameter, and the length of the zinc strip to be predicted.

[0009] In the above method, determining the service life of the zinc strip to be predicted based on the minimum cross-sectional diameter, corrosion allowance coefficient and corrosion rate of the zinc strip to be predicted includes determining by formula 1:

[0010]

[0011] Among them, T total is the service life of the zinc strip to be predicted, y; D1 is the minimum cross-sectional diameter of the zinc strip to be predicted, mm; η is the corrosion allowance coefficient of the zinc strip to be predicted, which is 6-10; v is the corrosion rate of the zinc strip to be predicted, mm / y.

[0012] The method described above, wherein the corrosion rate of the zinc strip to be predicted is determined based on the surface area, density, alternating current flowing through the surface, relative atomic mass of zinc, number of electrons of zinc ions, and alternating current efficiency of the zinc strip to be predicted, comprises determining it through Formula 2:

[0013]

[0014] Where k is the prediction factor, which is 2.94 mol / C; I rms is the alternating current flowing through the surface of the zinc strip to be predicted, A; M is the relative atomic mass of zinc; C E is the AC current efficiency, which is 3-5%; n is the number of electrons in the zinc ion; S is the surface area of ​​the zinc strip to be predicted, m 2 ; ρ is the density of the zinc strip to be predicted, kg / m 3 .

[0015] In the above method, determining the surface area of ​​the zinc strip to be predicted based on the minimum cross-sectional diameter, the maximum cross-sectional diameter, and the length of the zinc strip to be predicted includes determining it through Formula 3:

[0016]

[0017] Wherein, D2 is the maximum cross-sectional diameter of the zinc strip to be predicted, in mm; L is the length of the zinc strip to be predicted, in m.

[0018] As described above, the I rms Calculated by formula 4:

[0019]

[0020] Wherein, R is the resistance value of the resistor connected between the zinc strip to be predicted and the buried pipeline, Ω; U is the voltage of the resistor, V.

[0021] According to the method described above, the voltage of the resistor is determined by the following method:

[0022] Performing a first test, a second test, and a third test on the resistor respectively to obtain a first voltage, a second voltage, and a third voltage;

[0023] When the absolute value of the difference between any two of the first voltage, the second voltage, and the third voltage is less than or equal to 0.1V, the voltage of the resistor is any one of the first voltage, the second voltage, and the third voltage;

[0024] When the absolute value of the difference between any two of the first voltage, the second voltage, and the third voltage is greater than 0.1V, the voltage of the resistor continues to be detected until the absolute value of the difference between any two of the first voltage, the second voltage, and the third voltage is less than or equal to 0.1V.

[0025] According to the above method, the remaining service life of the zinc strip to be predicted is calculated by formula 5:

[0026] T r =T toal -T p Formula 5,

[0027] Among them, T r is the remaining service life of the zinc strip to be predicted, y; T p is the service life of the zinc strip to be predicted, y.

[0028] According to the above method, when the regional level is level 1, the corrosion allowance coefficient η is 6;

[0029] And / or, when the regional level is level 2, the corrosion allowance coefficient η is 8;

[0030] And / or, when the regional level is level 3, the corrosion allowance coefficient η is 9;

[0031] And / or, when the regional level is level four, the corrosion allowance coefficient η is 10.

[0032] The present invention provides a method for predicting the life of a zinc strip. The method is based on the minimum cross-sectional diameter, corrosion allowance coefficient, and corrosion rate of the zinc strip to be predicted. These physical or chemical parameters directly reflect the corrosion behavior and performance changes of the zinc strip under specific environments, avoiding errors caused by a single factor, and thus achieving high prediction accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present invention or related technologies. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0034] Figure 1 A schematic cross-sectional view of a zinc strip provided by the present invention;

[0035] Figure 2 This is a schematic diagram of a zinc strip anti-AC interference provided by the present invention. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0037] The present invention provides a method for predicting the life of a zinc strip, comprising the following steps:

[0038] The service life of the zinc strip to be predicted is determined according to the minimum cross-sectional diameter, corrosion allowance coefficient and corrosion rate of the zinc strip to be predicted.

[0039] The cross-sectional diameter of the zinc strip to be predicted in the present invention can be referred to Figure 1 A schematic diagram of a zinc strip cross section is shown in FIG. A steel core is provided within the zinc strip. D1 represents the minimum cross-sectional diameter of the zinc strip, and D2 represents the maximum cross-sectional diameter of the zinc strip. The present invention does not limit the method for obtaining the minimum cross-sectional diameter. For example, the minimum cross-sectional diameter can be obtained by manual measurement, with the minimum cross-sectional diameter of the zinc strip taken as the minimum cross-sectional diameter. Alternatively, the minimum cross-sectional diameter can be obtained by querying the zinc strip factory specification parameter table.

[0040] The corrosion allowance factor (CAF) is a parameter used to describe the corrosion rate of zinc strip in a specific environment. It is typically determined based on the strip's material, the corrosiveness of the environment, temperature, humidity, and other factors that may affect the corrosion rate. The specific CAF varies depending on the application and type of zinc strip.

[0041] Corrosion rate is an important indicator for evaluating the service performance of zinc strip. It represents the weight loss of zinc strip per unit time, or the thickness loss per unit area per unit time. The application of corrosion rate helps predict the service life of zinc strip and better assess the degree of damage during use.

[0042] The method for determining the service life of a zinc strip provided by the present invention is based on the minimum cross-sectional diameter, corrosion allowance coefficient, and corrosion rate of the zinc strip to be predicted. These physical or chemical parameters directly reflect the corrosion behavior and performance changes of the zinc strip under specific environments, avoiding errors caused by a single factor, and thus achieving high prediction accuracy.

[0043] In some embodiments of the present invention, the method further includes determining the corrosion rate of the zinc strip to be predicted based on the surface area, density, alternating current flowing through the surface, relative atomic mass of zinc, number of electrons of zinc ions, and alternating current efficiency of the zinc strip to be predicted.

[0044] In the present invention, the corrosion rate of the zinc strip is related to the parameters to be predicted, including the surface area, density, AC current flowing through the zinc strip surface, relative atomic mass of zinc, number of electrons in the zinc ion, and AC current efficiency. The density, relative atomic mass, and number of electrons in the zinc ion are generally fixed values, while the surface area and current flowing through the zinc strip surface are calculated based on test results.

[0045] In AC interference protection, AC current efficiency significantly affects the corrosion rate of zinc strips. AC current efficiency refers to the ratio of the current actually used to produce a useful effect to the total current flowing through a conductor. The AC current efficiency is directly related to the corrosion rate of the zinc strip. When the AC current efficiency is low, the zinc strip corrodes more slowly at the same AC current. When the AC current efficiency is high, the zinc strip corrodes more quickly at the same AC current.

[0046] The present invention comprehensively considers the physical and chemical properties of the zinc strip, as well as the influence of alternating current, and can more comprehensively reflect the corrosion behavior of the zinc strip under specific environments. By comprehensively considering multiple factors, the corrosion rate of the zinc strip can be determined more accurately, avoiding errors caused by a single factor.

[0047] In some embodiments of the present invention, the method further includes: determining the surface area of ​​the zinc strip to be predicted based on the minimum cross-sectional diameter, the maximum cross-sectional diameter, and the length of the zinc strip to be predicted.

[0048] The present invention does not limit the method for obtaining the maximum cross-sectional diameter. For example, the maximum cross-sectional diameter of the zinc strip can be obtained by manual measurement, with the maximum cross-sectional diameter of the zinc strip being used as the maximum cross-sectional diameter. Alternatively, the maximum cross-sectional diameter can be obtained by querying the zinc strip factory specification parameter table. The length of the zinc strip to be predicted can be obtained by manual measurement.

[0049] This method determines the surface area of ​​zinc strip based on the minimum and maximum cross-sectional diameters, as well as the length, of the strip to be predicted. This method more accurately reflects the strip's true cross-sectional shape and size, as well as its length, particularly when the cross-sectional shape is irregular. Compared to using only a single diameter, this method more accurately calculates the strip's surface area. Because different zinc strip products may have different cross-sectional shapes and sizes, combining the minimum and maximum cross-sectional diameters allows this method to be applied to a variety of zinc strip cross-sectional shapes, offering broader applicability.

[0050] The present invention determines the surface area of ​​the zinc strip according to the minimum cross-sectional diameter, the maximum cross-sectional diameter and the length of the zinc strip, which can more accurately reflect the true shape and size of the cross-sectional area of ​​the zinc strip, making the obtained surface area more accurate.

[0051] In some embodiments of the present invention, determining the service life of the zinc strip to be predicted based on the minimum cross-sectional diameter, corrosion allowance coefficient, and corrosion rate of the zinc strip to be predicted comprises determining by formula 1:

[0052]

[0053] Among them, T total is the service life of the zinc strip to be predicted, y; D1 is the minimum cross-sectional diameter of the zinc strip to be predicted, mm; η is the corrosion allowance coefficient of the zinc strip to be predicted, which is 6-10; v is the corrosion rate of the zinc strip to be predicted, mm / y.

[0054] It can be understood that after obtaining the minimum cross-sectional diameter D1 of the zinc strip to be predicted, the corrosion rate v of the zinc strip to be predicted, and determining the value of the corrosion allowance coefficient η of the zinc strip to be predicted, they can be directly substituted into the above formula 1 to calculate the service life of the zinc strip to be predicted.

[0055] The corrosion allowance coefficient η can take different values ​​depending on the regional level, generally ranging from 6 to 10, for example, 6, 7, 8, 9, or 10. Specific regional classifications can be found in the "Design Specifications for Gas Pipeline Engineering" or the "Design Specifications for Oil Pipeline Engineering." These can be divided into Level 1, Level 2, Level 3, and Level 4 regions. If the zinc strip to be tested is located in a Level 4 environment, the corrosion allowance coefficient η can be appropriately increased to ensure safety, allowing for a more accurate calculation of the strip's service life.

[0056] The present invention calculates the service life of the zinc strip to be predicted by formula 1, so that the obtained result is more accurate.

[0057] In some embodiments of the present application, the corrosion rate of the zinc strip to be predicted is determined according to the surface area, density, alternating current flowing through the surface of the zinc strip to be predicted, relative atomic mass of zinc, number of electrons of zinc ions, alternating current efficiency, comprising determining by formula 2:

[0058]

[0059] wherein k is a prediction factor, taking 2.94 mol / C; I rms is the alternating current flowing through the surface of the zinc strip to be predicted, A; M is the relative atomic mass of zinc; C E is the alternating current efficiency, taking 3-5%; n is the number of electrons of zinc ions; S is the surface area of the zinc strip to be predicted, m 2 ; ρ is the density of the zinc strip to be predicted, kg / m 3 .

[0060] It can be understood that the alternating current I rms flowing through the surface of the zinc strip to be predicted and the surface area S of the zinc strip to be predicted need to be tested and calculated, k is a prediction factor, generally taking 2.94 mol / C, the relative atomic mass M of zinc generally takes 65 kg / mol, the number of electrons n of zinc ions generally takes 2, the density ρ of the zinc strip to be predicted generally takes 7.14×10 3 kg / m 3 , and after determining the value of the alternating current efficiency C E , the corrosion rate of the zinc strip to be predicted can be directly calculated by substituting into the above formula 2.

[0061] wherein the alternating current efficiency C E may take different values according to the size of the current density i ac , generally taking any one value between 3-5%, for example, 3%, 4%, 5%. It can be understood that the current density refers to the amount of electricity flowing through the cross section of the conductor per unit area, that is, I rms / S. When the alternating current efficiency C E takes a larger value, the corrosion rate of the zinc strip is faster, and the service life of the zinc strip is shorter; when the alternating current efficiency C E takes a smaller value, the corrosion rate of the zinc strip is slower, and the service life of the zinc strip is longer.

[0062] The present application calculates the corrosion rate of the zinc strip to be predicted by formula 2, which comprehensively considers various factors, so that the accuracy of the obtained corrosion rate result is higher.

[0063] In some embodiments of the present application, the surface area of the zinc strip to be predicted is determined according to the minimum cross-sectional diameter, maximum cross-sectional diameter, length of the zinc strip to be predicted, comprising determining by formula 3:

[0064]

[0065] Wherein, D2 is the maximum cross-sectional diameter of the zinc strip to be predicted, in mm; L is the length of the zinc strip to be predicted, in m.

[0066] It can be understood that after obtaining the minimum cross-sectional diameter D1, the maximum cross-sectional diameter D2, and the length L of the zinc strip to be predicted, they can be directly substituted into the above formula 3 to calculate the surface area of ​​the zinc strip to be predicted.

[0067] The present invention calculates the surface area of ​​the zinc strip to be predicted by using Formula 3, taking into account the shape and size of the zinc strip cross section and the length of the zinc strip, so that the surface area result of the zinc strip can be obtained with higher accuracy.

[0068] In some embodiments of the present invention, the I rms Calculated by formula 4:

[0069]

[0070] Wherein, R is the resistance value of the resistor connected between the zinc strip to be predicted and the buried pipeline, Ω; U is the voltage of the resistor, V.

[0071] Figure 2 This is a schematic diagram of a zinc strip anti-AC interference provided by the present invention. Figure 2 As shown in the figure, the zinc strip and the pipeline are connected by a zinc strip cable, a pipeline cable and a terminal. An AC drain is connected between the zinc strip cable and a terminal, and a standard resistor is connected between the two terminals. The standard resistor is located above the ground. The AC interference voltage U at both ends of the standard resistor is tested. Then, the voltage U and the resistance R are substituted into the above formula 4 to calculate the AC current I flowing through the surface of the zinc strip to be predicted. rms .

[0072] The present invention does not limit the test method of the AC interference voltage U across the resistor. For example, the AC interference voltage U across the resistor can be obtained by testing the voltage with a multimeter, or by a preset voltage detection device.

[0073] The present invention calculates the AC current I flowing through the zinc strip surface to be predicted by formula 4: rms , which can make the current results more accurate.

[0074] In some embodiments of the present invention, the voltage of the resistor is determined by the following method:

[0075] Performing a first test, a second test, and a third test on the resistor respectively to obtain a first voltage, a second voltage, and a third voltage;

[0076] When the absolute value of the difference between any two of the first voltage, the second voltage and the third voltage is less than or equal to 0.1V, then the voltage of the resistor is any one of the first voltage, the second voltage and the third voltage;

[0077] When the absolute value of the difference between any two of the first voltage, the second voltage and the third voltage is greater than 0.1V, then the voltage of the resistor is continuously detected until the absolute value of the difference between any two of the first voltage, the second voltage and the third voltage is less than or equal to 0.1V.

[0078] It can be understood that, in the initial stage of burying the zinc strip in the ground to resist alternating current interference, the alternating current interference voltage between the two ends of the resistor is tested, and the obtained voltage value is unstable. After a certain period of time, the voltage value obtained by testing tends to be stable.

[0079] The resistor is continuously detected three times to obtain three same or different voltages; when the absolute value of the difference between any two of the three voltages is less than or equal to 0.1V, it is considered that the alternating voltage between the two ends of the resistor tends to be stable, and the alternating voltage between the two ends of the resistor can be selected as any one of the three obtained voltages; when the absolute value of the difference between any two of the three voltages is greater than 0.1V, it is considered that the alternating voltage between the two ends of the resistor has not reached a stable state, and the alternating voltage between the two ends of the resistor can be continuously tested until the stable state is reached.

[0080] In the present application, when the voltage between the two ends of the resistor is determined, the value is taken after testing is stable, which can improve the accuracy of the obtained voltage.

[0081] In some embodiments of the present application, the remaining service life of the zinc strip to be predicted is calculated by formula 5:

[0082] T r = T toal -T p , formula 5,

[0083] Wherein, T r is the remaining service life of the zinc strip to be predicted, y; T p is the service life of the zinc strip to be predicted, y.

[0084] In the present application, after the service life T total of the zinc strip to be predicted and the service life T p of the zinc strip to be predicted are determined, the remaining service life T r of the zinc strip to be predicted can be calculated by substituting the above formula 5, that is, the service life T total of the zinc strip to be predicted minus the service life T p of the zinc strip to be predicted, that is, the remaining service life T r of the zinc strip to be predicted.

[0085] The application can accurately predict the remaining service life of the zinc strip, ensure timely replacement or repair of the zinc strip before failure, avoid safety accidents, and thus ensure stable operation of the system and safety of personnel.

[0086] In some embodiments of the application, when the current density is i ac ≤50A / m 2 , the C E is 5%;

[0087] and / or, when the current density i ac =100A / m 2 , the C E is 4%;

[0088] and / or, when i ac =200A / m 2 , the C E is 3.5%;

[0089] and / or, when i ac ≥300A / m 2 , the C E is 3%;

[0090] and / or, when the region level is first, the η is 6;

[0091] and / or, when the region level is second, the η is 8;

[0092] and / or, when the region level is third, the η is 9;

[0093] and / or, when the region level is fourth, the η is 10.

[0094] In the application, the C E is valued according to different current densities; and / or, the η is valued according to different region levels, and the accuracy of the service life of the zinc strip to be predicted obtained finally can be further improved according to the valuation method of the application.

[0095] The technical solutions of the application are further described below in combination with specific examples.

[0096] Example 1

[0097] A buried natural gas pipeline is parallel to an 800kV high-voltage alternating current transmission line for 10km, the induced alternating current interference voltage on the pipeline is from 25V to 75V, and the alternating current density is from 2000A / m 2 to 6700A / m 2, the AC interference risk is high, and AC mitigation measures need to be taken. The mitigation measures of shallowly buried zinc strips are designed and selected, and shallowly buried zinc strips are parallel to the pipeline in the position with high interference risk. After construction, the AC current density along the pipeline is reduced to 30 A / m 2 After the zinc strip has been in service for 5 and a half years, the remaining life of the zinc strip needs to be evaluated.

[0098] The method for predicting the life of the zinc strip of the present embodiment includes the following steps:

[0099] 1) By querying the minimum cross-sectional diameter D1 of the ZR4 type zinc strip in the zinc strip factory specification parameter table is 8.73 mm, the maximum cross-sectional diameter D2 is 10.32 mm, and by measuring the length L of the zinc strip is 100 m. The surface area of the zinc strip is calculated:

[0100]

[0101] 2) A standard resistance with a resistance of 1Ω is connected between the zinc strip and the natural gas pipeline using a cable, and the AC voltages at both ends are continuously measured using a multimeter to be 112V, 119.95V, 112.08V, respectively. The difference between any two AC voltages is less than 0.1V, the AC voltage tends to be stable, and the AC voltage is taken as 112V. The AC current flowing through the surface of the zinc strip is calculated:

[0102]

[0103] 3) The relative atomic mass M of zinc is taken as 65 kg / mol, the number of electrons n of zinc ions is taken as 2, the density p of the zinc strip is taken as 7.14×10 3 kg / m 3 , the current density is 41 A / m 2 , the AC current efficiency C E is taken as 5%, and the corrosion rate of the zinc strip under the action of the AC current is calculated:

[0104]

[0105] 4) The area is rated as level two, the corrosion allowance coefficient η of the zinc strip is taken as 8, and the service life of the zinc strip under the action of the AC current is predicted:

[0106]

[0107] 5) The remaining service life of the zinc strip under the action of the AC interference is calculated:

[0108] T r =T toal -T p ≈33y

[0109] That is, the zinc strip needs to be replaced within 33 years.

[0110] Examples 2-4

[0111] The methods for predicting the life of the zinc strip in Examples 2-4 are basically the same as those in Example 1, except that the current density is different and the AC current efficiency C E The specific results are shown in Table 1.

[0112] Examples 5-7

[0113] The methods for predicting the life of the zinc strip in Examples 5-7 are essentially the same as those in Example 1, except that the corrosion allowance coefficient η is taken differently for different regional levels. Specific results are shown in Table 1.

[0114] Comparative Example 1

[0115] The method for predicting the life of the zinc strip in Comparative Example 1 is basically the same as that in Example 1, except that the current density and regional grade are not considered, and the AC current efficiency C is not considered. E and corrosion allowance coefficient η. Specific results are shown in Table 1.

[0116] Table 1

[0117]

[0118] It can be seen from Table 1 that, compared with the comparative example, the method for predicting the life of the zinc strip provided by the present invention has higher accuracy.

[0119] From the comparison between Examples 1-7 and Comparative Example 1, it can be seen that the method for predicting the life of the zinc strip provided by the present invention is relatively close to the actual service life and has high accuracy.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for predicting the life of a zinc strip, characterized in that: The following steps are involved: The service life of the zinc strip to be predicted is determined according to the minimum cross-sectional diameter, corrosion allowance coefficient and corrosion rate of the zinc strip to be predicted.

2. The method according to claim 1, characterized in that Also includes: The corrosion rate of the zinc strip to be predicted is determined according to the surface area, density, alternating current flowing through the surface, relative atomic mass of zinc, number of electrons of zinc ions, and alternating current efficiency of the zinc strip to be predicted.

3. The method according to claim 2, characterized in that Also includes: The surface area of ​​the zinc strip to be predicted is determined according to the minimum cross-sectional diameter, the maximum cross-sectional diameter, and the length of the zinc strip to be predicted.

4. The method according to claim 1, wherein Determining the service life of the zinc strip to be predicted based on the minimum cross-sectional diameter, corrosion allowance coefficient, and corrosion rate of the zinc strip to be predicted includes determining by formula 1: Among them, T total is the service life of the zinc strip to be predicted, y; D1 is the minimum cross-sectional diameter of the zinc strip to be predicted, mm; η is the corrosion allowance coefficient of the zinc strip to be predicted, which is 6-10; v is the corrosion rate of the zinc strip to be predicted, mm / y.

5. The method according to claim 2, characterized in that Determining the corrosion rate of the zinc strip to be predicted based on the surface area, density, alternating current flowing through the surface, relative atomic mass of zinc, number of electrons of zinc ions, and alternating current efficiency of the zinc strip to be predicted includes determining it through Formula 2: Where k is the prediction factor, which is 2.94 mol / C; I rms is the alternating current flowing through the surface of the zinc strip to be predicted, A; M is the relative atomic mass of zinc; C E is the AC current efficiency, which is 3-5%; n is the number of electrons in the zinc ion; S is the surface area of ​​the zinc strip to be predicted, m 2 ; ρ is the density of the zinc strip to be predicted, kg / m 3 .

6. The method according to claim 3, characterized in that Determining the surface area of ​​the zinc strip to be predicted based on the minimum cross-sectional diameter, the maximum cross-sectional diameter, and the length of the zinc strip to be predicted includes determining it through Formula 3: Wherein, D2 is the maximum cross-sectional diameter of the zinc strip to be predicted, in mm; L is the length of the zinc strip to be predicted, in m.

7. The method according to claim 5, characterized in that I rms Calculated by formula 4: Wherein, R is the resistance value of the resistor connected between the zinc strip to be predicted and the buried pipeline, Ω; U is the voltage of the resistor, V.

8. The method according to claim 7, characterized in that The voltage across the resistor is determined by: Performing a first test, a second test, and a third test on the resistor respectively to obtain a first voltage, a second voltage, and a third voltage; When the absolute value of the difference between any two of the first voltage, the second voltage, and the third voltage is less than or equal to 0.1V, the voltage of the resistor is any one of the first voltage, the second voltage, and the third voltage; When the absolute value of the difference between any two of the first voltage, the second voltage, and the third voltage is greater than 0.1V, the voltage of the resistor continues to be detected until the absolute value of the difference between any two of the first voltage, the second voltage, and the third voltage is less than or equal to 0.1V.

9. The method according to any one of claims 1 to 8, characterized in that The remaining service life of the zinc strip to be predicted is calculated by formula 5: T r =T toal -T p Formula 5, Among them, T r is the remaining service life of the zinc strip to be predicted, y; T p is the service life of the zinc strip to be predicted, y.

10. The method according to claim 4, characterized in that When the regional level is level 1, η is 6; And / or, when the regional level is level 2, η is 8; And / or, when the regional level is level 3, η is 9; And / or, when the regional level is level four, the η is 10.

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