A method and system for automatic evaluation of cementing quality

Abstract

The application discloses a cementing quality automatic evaluation processing method and system, and the method comprises the following steps: S1, performing time domain to frequency domain transformation on 5ft full wave trains in variable density logging point by point; S2, performing energy analysis on each frequency of the 5ft full wave trains in the frequency domain, and calculating the energy of the corresponding frequency spectrum; S3, after dividing the energy of the frequency spectrum into direct wave energy, formation wave energy and casing wave energy in a preset range from small to large in turn, determining the energy spectrum range of the formation wave and the casing wave corresponding to the formation wave energy and the casing wave energy; S4, calibrating the energy spectrum of the formation wave and the casing wave, and calculating the cementation index BI1 of the first interface and the cementation index BI2 of the second interface; S5, performing smoothing processing on the cementation indexes BI1 and BI2; and S6, converting the cementation indexes BI1 and BI2 into the cementing quality information corresponding to the 5ft full wave trains according to a preset rule. The processing time is efficient, the interpretation accuracy is high, and automatic evaluation can be realized.

Description

Technical Field

[0001] This invention relates to the field of oil well logging technology, and in particular to an automatic evaluation and processing method and system for cementing quality. Background Technology

[0002] Currently, although the application of new energy sources is becoming increasingly widespread and their proportion is growing, fossil fuels still hold a dominant position in the energy landscape. However, in some specialized industries, the role of traditional fossil fuels is irreplaceable. For example, using diesel locomotives on high-altitude terrain or in special vehicles like armored vehicles, where all-electric propulsion might lead to reliability issues, necessitates the use of traditional energy sources such as oil and coal. Therefore, oil exploration is indispensable, and well drilling is essential. Even within new energy sources, there are specific well-drilling operations that require specific methods, such as the extraction of hot dry rock. Therefore, the quality of well cementing needs to be assessed to ensure the reliability and safety of subsequent operations.

[0003] Currently, cementing quality evaluation mainly includes the evaluation of the first interface and the evaluation of the second interface. The evaluation of the first interface is achieved through software processing, while the evaluation of the second interface (i.e., the cement sheath and formation bonding condition) is based on the analysis of the strength of the casing wave, the shape and strength of the formation wave, and combined with the bonding condition of the first interface, and is evaluated manually and qualitatively.

[0004] In the field of oil well logging technology, the evaluation of the second interface of cementing quality is mostly carried out manually in segments. However, the cementing quality inspection logging of a single well consists of at least one segment and sometimes several segments; a segment can be hundreds of meters long or even thousands of meters long. When the interpretation segment is long and the cementing is complex, interpreters spend a lot of time and effort adding segments at three levels (good, medium, and poor) one by one for interpretation. If the number of evaluation segments reaches thousands, the workload for interpreters is enormous, the timeliness is low, and the physical harm is significant. For a long time, automatic evaluation of the second interface of cementing quality has been a major challenge for software developers. Many companies, research institutions, and production units have explored various automatic processing methods, but no effective breakthrough has been achieved. The compliance rate of automatic quantitative interpretation is less than half that of manual interpretation, and the workload of implementing human-machine joint interpretation through this quantitative method far exceeds that of manual interpretation alone.

[0005] Based on an understanding of domestic and international cementing quality evaluation methods, it is clear that no successful automated method or software for quantitative evaluation of the second interface has yet been developed in the field of petroleum logging technology. Therefore, the design and development of an automated cementing quality evaluation method and software is imperative. Summary of the Invention

[0006] The purpose of this invention is to provide an automatic cementing quality evaluation and processing method and system, which improves the timeliness and interpretation accuracy of cementing quality processing, and increases the compliance rate of automatic cementing quality evaluation.

[0007] To address the aforementioned technical problems, embodiments of the present invention provide an automatic cementing quality evaluation and processing method, comprising:

[0008] S1, perform time-domain to frequency-domain transformation on the 5ft full wave train in variable density logging point by point;

[0009] S2, perform energy analysis on the 5ft full-wave train at each frequency in the frequency domain, and calculate the energy of the corresponding spectrum;

[0010] S3, after dividing the energy of the spectrum from small to large into direct wave energy, formation wave energy and casing wave energy according to a preset range, determine the energy spectrum range of the formation wave energy and the casing wave energy corresponding to the formation wave energy and the casing wave energy;

[0011] S4, calibrate the energy spectra of the formation wave and the casing wave, and calculate and evaluate the cementation index BI1 of the first interface and the cementation index BI2 of the second interface.

[0012] S5, smooth out the bonding indices BI1 and BI2;

[0013] S6, according to preset rules, convert the cementation indices BI1 and BI2 into cementing quality information corresponding to the 5ft full wave train.

[0014] Wherein, S5 includes:

[0015] The cementation indices BI1 and BI2 were smoothed using a three-point averaging method.

[0016] Wherein, S1 includes:

[0017] The 5ft full-wave train is transformed from the time domain to the frequency domain point by point using Fourier transform or fast Fourier transform.

[0018] Specifically, the 5ft full-wave train is transformed from the time domain to the frequency domain point by point using Fourier transform, including the use of the Fourier transform formula:

[0019]

[0020] In the formula, X k It is the Fourier amplitude.

[0021] Wherein, the 2 includes:

[0022] The energy of the corresponding spectrum at the given location is calculated using equation (2).

[0023]

[0024] In the formula, X n X represents the energy value at a certain point. r X is the real part of the waveform after Fourier transform; m This is the corresponding imaginary part.

[0025] Wherein, S4 includes:

[0026] From the energy spectrum range of the casing wave, select the maximum casing energy C. max Minimum energy of formation waves F min ;

[0027] From the energy spectrum range of the formation waves, select the minimum casing energy C at the depth point where the formation wave energy is at its maximum. min and the maximum energy of the formation wave F max Calculate according to equations (3) and (4):

[0028]

[0029]

[0030] Wherein, S4 includes

[0031] Determine whether the strata contain at least two of the following: mudstone, coal seam, limestone, and sandstone;

[0032] If so, calculate BI2 using the energy ratio method according to equation (5):

[0033]

[0034] Where, ∑E C The sum of the casing wave energy at the current depth point; ∑E F This represents the sum of the energy of the formation waves at the current depth.

[0035] In addition, another embodiment of this application includes an automatic cementing quality evaluation and processing system, comprising:

[0036] The frequency domain transformation module is used to transform the 5ft full wave train in variable density logging point by point from the time domain to the frequency domain.

[0037] The energy spectrum analysis module is used to perform energy analysis on the 5ft full-wave train at each frequency in the frequency domain and calculate the energy of the corresponding spectrum.

[0038] The specified spectrum determination module is used to divide the energy of the spectrum from small to large into direct wave energy, formation wave energy and casing wave energy according to a preset range, and then determine the energy spectrum range of the formation wave energy and casing wave energy corresponding to the formation wave energy and casing wave energy.

[0039] The interface cementation index calculation module is used to calibrate the energy spectra of the formation wave and the casing wave, and to calculate and evaluate the cementation index BI1 of the first interface and the cementation index BI2 of the second interface.

[0040] The cementation index processing module is used to smooth the cementation indices BI1 and BI2.

[0041] The automatic evaluation module converts the cementation indices BI1 and BI2 into cementing quality information corresponding to the 5ft full wave train according to preset rules.

[0042] The interface cementation index calculation module includes a parameter acquisition unit, a first interface cementation index calculation unit, and a second interface cementation index calculation unit. The parameter acquisition unit is connected to the specified spectrum determination module and is used to select the maximum sleeve energy C from the energy spectrum range of the sleeve wave. max Minimum energy of formation waves F min From the energy spectrum range of the formation waves, the minimum casing energy C is selected at the depth point where the formation wave energy is at its maximum. min and the maximum energy of the formation wave F max The bonding index calculation unit of the first interface is calculated using formula (3):

[0043]

[0044] After determining that the stratum consists of only one of mudstone, coal seam, limestone, or sandstone, the second interface cementation index calculation unit uses formula (4) for calculation:

[0045]

[0046] After determining that the strata contain at least two of mudstone, coal seam, limestone, and sandstone, the second interface cementation index calculation unit calculates BI2 using the energy ratio method according to equation (5):

[0047]

[0048] Where, ∑E C The sum of the casing wave energy at the current depth point; ∑E F This represents the sum of the stratum wave energies at the current depth.

[0049] The automatic cementing quality evaluation and processing method and system provided in this invention have the following advantages compared with the prior art:

[0050] The automatic cementing quality evaluation method and system provided in this invention first performs a time-domain to frequency-domain transformation, then calculates the energy of the spectrum, and then divides the energy of the spectrum into direct wave energy, formation wave energy, and casing wave energy according to a preset range from small to large. The energy spectrum ranges of the formation wave energy and the casing wave energy are then determined. Finally, the energy spectra of the formation wave and the casing wave are calibrated, and the cementing index BI1 of the first interface and the cementing index BI2 of the second interface are calculated and evaluated. Cementing quality can be obtained through the cementing index, with high timeliness and accuracy, improving the timeliness and interpretation accuracy of cementing quality processing, and increasing the automatic cementing quality evaluation compliance rate. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 A 5ft full-wavelength time domain waveform diagram from one embodiment of the automatic cementing quality evaluation and processing method provided in this invention.

[0053] Figure 2 A 5ft full-wavelength energy spectrum is shown in one embodiment of the automatic cementing quality evaluation and processing method provided by the present invention.

[0054] Figure 3 A schematic flowchart of one embodiment of the automatic cementing quality evaluation and processing method provided by the present invention;

[0055] Figure 4 This is a schematic diagram of a structure in one embodiment of the automatic cementing quality evaluation and processing system provided in this invention. Detailed Implementation

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] Please refer to Figure 1-4 , Figure 1 A 5ft full-wavelength time domain waveform diagram from one embodiment of the automatic cementing quality evaluation and processing method provided in this invention. Figure 2 A 5ft full-wavelength energy spectrum is shown in one embodiment of the automatic cementing quality evaluation and processing method provided by the present invention. Figure 3 A schematic flowchart of one embodiment of the automatic cementing quality evaluation and processing method provided by the present invention; Figure 4 This is a schematic diagram of a structure in one embodiment of the automatic cementing quality evaluation and processing system provided in this invention.

[0058] In one specific embodiment, the automatic cementing quality evaluation and processing method includes:

[0059] S1, perform time-domain to frequency-domain transformation on the 5ft full wave train in variable density logging point by point;

[0060] S2, perform energy analysis on the 5ft full-wave train at each frequency in the frequency domain, and calculate the energy of the corresponding spectrum;

[0061] S3, after dividing the energy of the spectrum from small to large into direct wave energy, formation wave energy and casing wave energy according to a preset range, determine the energy spectrum range of the formation wave energy and the casing wave energy corresponding to the formation wave energy and the casing wave energy;

[0062] S4, calibrate the energy spectra of the formation wave and the casing wave, and calculate and evaluate the cementation index BI1 of the first interface and the cementation index BI2 of the second interface.

[0063] S5, smooth out the bonding indices BI1 and BI2;

[0064] S6, according to preset rules, convert the cementation indices BI1 and BI2 into cementing quality information corresponding to the 5ft full wave train.

[0065] By first performing a time-domain to frequency-domain transformation, then calculating the energy of the spectrum, and then dividing the energy of the spectrum into direct wave energy, formation wave energy, and casing wave energy according to a preset range from small to large, the energy spectrum ranges of the formation wave energy and the casing wave energy are determined. Finally, the energy spectra of the formation wave and the casing wave are calibrated, and the cementing index BI1 of the first interface and the cementing index BI2 of the second interface are calculated and evaluated. The cementing index can be used to obtain cementing quality, which is timely and accurate, improves the timeliness and interpretation accuracy of cementing quality processing, and improves the automatic processing and evaluation compliance rate of cementing quality.

[0066] The automatic cementing quality evaluation method in this application analyzes the variable density logging mechanism, uses Fourier transform to transform the 5ft full wave train from the time domain to the frequency domain, calculates the energy of each spectrum, and divides the energy spectrum into three parts: direct wave energy, formation wave energy, and casing wave energy, thereby determining the energy spectrum range of formation wave and casing wave. Then, the energy spectrum is calibrated, and the cementing indices BI1 and BI2 of the first and second interfaces are calculated, thereby achieving a quantitative evaluation of the second interface.

[0067] In the automatic cementing quality evaluation method of this application, the stronger the signal and the greater the amplitude of the full-waveform formation acoustic wave, the darker the grayscale and the blacker the image, indicating a poorer cementing quality. Generally, the time period of the formation wave is between T1 = 400uS and T2 = 950uS. The values ​​of formation wave T1 and T2 are calculated according to the situation of each well.

[0068] The acoustic energy intensity of the formation wave at each sampling depth point of the appraisal well during the time period T1 and T2 is obtained by Fourier transform, and the average acoustic energy intensity PT of the time period T1-T2 is calculated.

[0069] The average acoustic energy intensity PT1, PT2, PT3...PTn of each sampling point is calculated for the entire Hs-He cementing section. The average acoustic energy intensity [PTpoor] for the worst cementing quality of the well is calculated, the average acoustic energy intensity [PTgood] for the best cementing quality of the well is calculated, and the average acoustic energy intensity [PTmedium] for the medium cementing quality is calculated. The computer automatically quantifies and evaluates the cementing quality of the entire well section using the evaluation criteria [PTgood], [PTmedium], and [PTpoor].

[0070] Since BI1 and BI2 may undergo abrupt changes due to random events in actual calculations, resulting in uneven curves and affecting the actual calculation results, in one embodiment, S5 includes:

[0071] The cementation indices BI1 and BI2 were smoothed using a three-point averaging method.

[0072] The smoothing process using the 3-point averaging method is as follows:

[0073] BI1 output data = (BI1[n] + BI1[n-1] + BI1[n-2]) / 3;

[0074] BI2 output data = (BI2[n] + BI2[n-1] + BI2[n-2]) / 3.

[0075] This application includes, but is not limited to, using the 3-point averaging method for smoothing; other algorithms may also be used for processing.

[0076] This application employs a point-by-point time-domain to frequency-domain transformation of the 5ft full-wave train in variable density logging. The specific algorithm is not limited. In one embodiment, S1 includes:

[0077] The 5ft full-wave train is transformed from the time domain to the frequency domain point by point using Fourier transform or fast Fourier transform.

[0078] This application includes, but is limited to, using Fourier transform or fast Fourier transform to perform point-by-point time-domain to frequency-domain transformation on the 5ft full-wave train. Fast Fourier transform (FFT) is typically used to reduce the amount of computer processing and improve the transformation speed.

[0079] This application does not limit the specific Fourier transform formula. In one embodiment, the step of performing a point-by-point time-domain to frequency-domain transformation of the 5ft full-wave train using Fourier transform includes using the following Fourier transform formula:

[0080]

[0081] In the formula, X k It is the Fourier amplitude.

[0082] The method for calculating the energy of the corresponding spectrum at each frequency in the frequency domain for energy analysis of the 5ft full-wave train is not limited. In one embodiment, step 2 includes:

[0083] The energy of the corresponding spectrum at the given location is calculated using equation (2).

[0084]

[0085] In the formula, X n X represents the energy value at a certain point. r X is the real part of the waveform after Fourier transform; m This is the corresponding imaginary part.

[0086] This application includes, but is not limited to, calculating the energy of the corresponding spectrum using Equation (2).

[0087] The energy calculated in this application is divided into three parts: direct wave energy, formation wave energy, and casing wave energy, thereby determining the energy spectrum range of formation wave and casing wave.

[0088] First, analyze the energy spectrum of the entire well section to determine the energy spectrum range of the casing wave and the direct wave. The middle part is the required formation wave region.

[0089] According to the formation wave propagation law of the second interface in cementing, when both the first and second interfaces of the formation are well cemented, the energy of the sound source is transmitted into the formation, and the energy of the returned received sound wave is very small. When the first interface is well cemented but the second interface is poorly cemented, the energy of the returned received sound wave is relatively strong. Based on the intensity of the sound wave, a sound wave intensity curve QXPJM is generated. The automatic evaluation of the second interface is based on this curve QXPJM. The calculation method of the sound wave intensity curve QXPJM is as follows:

[0090] 1. Cumulative calculation of acoustic intensity in the 320µs, 400µs-950µs acoustic energy spectrum;

[0091] 2. FQXPJM: Fourier Transform Calculation Method:

[0092] 3. IQXPJM: ∑sound intensity = P amplitude^2 / (2 * p medium density * V sound velocity), when the formation is not homogeneous;

[0093] 4. QXPJM: ∑sound intensity = ∑P amplitude^2. This method is used when the formation is relatively homogeneous.

[0094] 5. Generate an evaluation curve QXPJM using ∑ sound intensity.

[0095] Figure 3 This is a quantitative and qualitative evaluation chart of the cementing quality at interfaces I and II of Well A, under conditions of casing wave, formation wave, and direct wave. High values ​​of the casing wave amplitude, indicated by strain density, correspond to higher calculated casing wave energy spectrum amplitude and lower calculated BI1 values, indicating poor cementation at interface I. Conversely, lower casing wave amplitude corresponds to lower calculated casing wave energy, indicating good cementation quality at interface I. When the calculated BI1 is close to 1, interface I is rated as good. Corresponding to well sections with low casing wave energy and good interface cementation, higher calculated formation wave energy spectrum values ​​and higher calculated BI2 values ​​when the formation wave amplitude is high, the quality of interface II is rated as medium to good.

[0096] This application does not limit the specific method for calculating and evaluating the bonding index BI1 of interface I and the bonding index BI2 of interface II. In one embodiment, S4 includes:

[0097] From the energy spectrum range of the casing wave, select the maximum casing energy Cmax and the minimum formation wave energy Fmin;

[0098] From the energy spectrum range of the formation waves, select the minimum casing energy Cmin and the maximum formation wave energy Fmax at the depth point where the formation wave energy is maximum, and calculate them according to equations (3) and (4):

[0099]

[0100]

[0101] For strata with complex and varied lithology, such as those containing mudstone, coal seams, limestone, and sandstone, equation (4) is not well-suited due to the significant differences in their respective strata energy. To address this technical problem, in one embodiment, S4 includes...

[0102] Determine whether the strata contain at least two of the following: mudstone, coal seam, limestone, and sandstone;

[0103] If so, calculate BI2 using the energy ratio method according to equation (5):

[0104]

[0105] Where, ∑E C The sum of the casing wave energy at the current depth point; ∑E F This represents the sum of the stratum wave energies at the current depth.

[0106] This application does not limit the method for evaluating the quality of the second interface. In one embodiment, the second step is to evaluate the quality of the second interface.

[0107] H-value = Good evaluation = 15%, the standard for good cementing quality evaluation of interface II;

[0108] Z-value = 40% in the evaluation, standard for cementing quality evaluation of interface II;

[0109] C-value = evaluation difference = 80%, standard for evaluation difference of cementing quality at interface II.

[0110] In addition to the above, this application can also use other evaluation methods, such as using a percentage system. If the obtained BI2 data is 35%, it is calculated as 35 percent, then 100 - 35 = 65, resulting in an actual evaluation score of 65. In the actual evaluation, the evaluation result is output from the corresponding evaluation list according to the score. Alternatively, the corresponding data can be directly extracted from the corresponding list to output the corresponding evaluation result.

[0111] In addition, another embodiment of this application includes an automatic cementing quality evaluation and processing system, comprising:

[0112] Frequency domain transformation module 10 is used to perform time-domain to frequency domain transformation on a point-by-point basis of the 5ft full wave train in variable density logging.

[0113] Energy spectrum analysis module 20 is used to perform energy analysis on the 5ft full-wave train at each frequency in the frequency domain and calculate the energy of the corresponding spectrum.

[0114] The specified spectrum determination module 30 is used to divide the energy of the spectrum from small to large into direct wave energy, formation wave energy and casing wave energy according to a preset range, and then determine the energy spectrum range of the formation wave energy and casing wave energy corresponding to the formation wave energy and casing wave energy.

[0115] The interface cementation index calculation module 40 is used to calibrate the energy spectrum of the formation wave and the casing wave, and to calculate and evaluate the cementation index BI1 of the first interface and the cementation index BI2 of the second interface.

[0116] The cementation index processing module 50 is used to smooth the cementation indices BI1 and BI2.

[0117] The automatic evaluation module 60 converts the cementation indices BI1 and BI2 into cementing quality information corresponding to the 5ft full wave train according to preset rules.

[0118] Since the automatic cementing quality evaluation and processing system is the same system as the automatic cementing quality evaluation and processing method and has the same beneficial effects, this application will not elaborate on it.

[0119] This application does not limit the specific calculation method. In one embodiment, the interface bonding index calculation module includes a parameter acquisition unit, a first interface bonding index calculation unit, and a second interface bonding index calculation unit. The parameter acquisition unit is connected to the specified spectrum determination module and is used to select the maximum sleeve energy C from the energy spectrum range of the sleeve wave. max Minimum energy of formation waves F min From the energy spectrum range of the formation waves, the minimum casing energy C is selected at the depth point where the formation wave energy is at its maximum. min and the maximum energy of the formation wave F max The bonding index calculation unit of the first interface is calculated using formula (3):

[0120]

[0121] After determining that the stratum consists of only one of mudstone, coal seam, limestone, or sandstone, the second interface cementation index calculation unit uses formula (4) for calculation:

[0122]

[0123] After determining that the strata contain at least two of mudstone, coal seam, limestone, and sandstone, the second interface cementation index calculation unit calculates BI2 using the energy ratio method according to equation (5):

[0124]

[0125] Where, ∑EC The sum of the casing wave energy at the current depth point; ∑E F This represents the sum of the energy of the formation waves at the current depth.

[0126] This application includes, but is not limited to, the calculation methods described above.

[0127] In summary, the automatic cementing quality evaluation method and system provided in this embodiment of the invention first performs a time-domain to frequency-domain transformation, then calculates the energy of the spectrum, and then divides the energy of the spectrum into direct wave energy, formation wave energy, and casing wave energy in ascending order according to a preset range, thereby determining the energy spectrum range of the formation wave energy and the casing wave energy corresponding to the casing wave energy; finally, the energy spectra of the formation wave and the casing wave are calibrated, and the cementing index BI1 of the first interface and the cementing index BI2 of the second interface are calculated and evaluated; the cementing index can be used to obtain cementing quality, which is timely and accurate, improves the timeliness and interpretation accuracy of cementing quality processing, and improves the automatic cementing quality evaluation compliance rate.

[0128] The above provides a detailed description of the automatic cementing quality evaluation and processing method and system provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A method for automatically evaluating and processing cementing quality, characterized in that, include: S1, perform time-domain to frequency-domain transformation on the 5ft full wave train in variable density logging point by point; S2, perform energy analysis on each frequency in the frequency domain of the 5ft full-wave train and calculate the energy of the corresponding spectrum; S3, after dividing the energy of the spectrum from small to large into direct wave energy, formation wave energy and casing wave energy according to a preset range, determine the energy spectrum range of the formation wave energy and the casing wave energy corresponding to the formation wave energy and the casing wave energy; S4, calibrate the energy spectra of the formation wave and the casing wave, and calculate and evaluate the cementation index BI1 of the first interface and the cementation index BI2 of the second interface. S5, smooth out the bonding indices BI1 and BI2; S6, according to preset rules, convert the cementation indices BI1 and BI2 into cementing quality information corresponding to the 5ft full wave train. S5 includes: The cementation indices BI1 and BI2 are smoothed using a three-point averaging method. S1 includes: The 5ft full-wave train is subjected to a point-by-point time-domain to frequency-domain transformation using Fourier transform, including the use of the Fourier transform formula: , n=0,1,2,3...,N-1 (1), In the formula, It is the Fourier amplitude. S2 includes: The energy of the corresponding spectrum is calculated using equation (2). , n=0,1,2,3...,N-1 (2) In the formula, X n X represents the energy value at a certain point. r X is the real part of the waveform after Fourier transform; m For the corresponding imaginary part, S4 includes: From the energy spectrum range of the casing wave, select the maximum casing energy C. max Minimum energy of formation waves F min ; From the energy spectrum range of the formation waves, select the minimum casing energy C at the depth point where the formation wave energy is at its maximum. min and the maximum energy of the formation wave F max Calculate according to equations (3) and (4): （3）， （4）， S4 includes: Determine whether the strata contain at least two of the following: mudstone, coal seam, limestone, and sandstone; If so, calculate BI2 using the energy ratio method according to equation (5): （５）， in, The sum of the casing wave energy at the current depth point; This represents the sum of the energy of the formation waves at the current depth.

2. An automatic cementing quality evaluation and processing system, characterized in that, The automatic cementing quality evaluation and processing method according to claim 1 includes: The frequency domain transformation module is used to transform the 5ft full wave train in variable density logging point by point from the time domain to the frequency domain. The energy spectrum analysis module is used to perform energy analysis on each frequency in the frequency domain of the 5ft full-wave train and calculate the energy of the corresponding spectrum. The specified spectrum determination module is used to divide the energy of the spectrum into direct wave energy, formation wave energy and casing wave energy in ascending order according to a preset range, and then determine the energy spectrum range of the formation wave energy and casing wave energy corresponding to the formation wave energy and casing wave energy. The interface cementation index calculation module is used to calibrate the energy spectra of the formation wave and the casing wave, and to calculate and evaluate the cementation index BI1 of the first interface and the cementation index BI2 of the second interface. The cementation index processing module is used to smooth the cementation indices BI1 and BI2. The automatic evaluation module converts the cementation indices BI1 and BI2 into cementing quality information corresponding to the 5ft full wave train according to preset rules. The interface cementation index calculation module includes a parameter acquisition unit, a first interface cementation index calculation unit, and a second interface cementation index calculation unit. The parameter acquisition unit is connected to the specified spectrum determination module and is used to select the maximum sleeve energy C from the energy spectrum range of the sleeve wave. max Minimum energy of formation waves F min From the energy spectrum range of the formation waves, the minimum casing energy C is selected at the depth point where the formation wave energy is at its maximum. min and the maximum energy of the formation wave F max The bonding index calculation unit of the first interface is calculated using formula (3): （3）； After determining that the stratum consists of only one of mudstone, coal seam, limestone, or sandstone, the second interface cementation index calculation unit uses formula (4) for calculation: （4）， After determining that the strata contain at least two of mudstone, coal seam, limestone, and sandstone, the second interface cementation index calculation unit calculates BI2 using the energy ratio method according to formula (5): （５）， in, The sum of the casing wave energy at the current depth point; This represents the sum of the energy of the formation waves at the current depth.

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