A process method for correcting the coaxiality of a supercharger rotor

Abstract

The present application relates to the technical field of rotating dynamic equipment assembly and maintenance, and discloses a rotor coaxiality correction process method for a supercharger, which utilizes a three-dimensional laser measuring device to establish a global measurement coordinate system, obtains an initial misalignment amount and performs cold-state safety initial alignment; after the unit reaches a hot stable operation condition, direct current gap voltage data of an eddy current displacement probe are collected and converted into one-way radial displacement amount; through coordinate conversion by a projection relationship matrix, a hot-state center displacement vector is obtained; then spatial axis extrapolation is performed to obtain a hot-state center offset vector and a hot-state angular misalignment amount at the end surface of the coupling; cold-state pre-offset compensation calculation is performed based on the hot-state center offset vector and the hot-state angular misalignment amount to generate correction target parameters; a gasket combination scheme and a transverse micro displacement amount are output according to the correction target parameters to adjust the base adjustment mechanism. The method can compensate for the operating state offset caused by thermal expansion and oil film uplift and improve the hot-state coaxiality correction accuracy.

Description

Technical Field

[0001] This invention relates to the field of rotary equipment assembly and maintenance technology, specifically a process for correcting the coaxiality of a rotor for a booster compressor. Background Technology

[0002] The booster compressor is a core piece of rotating equipment in chemical and energy production lines. The rotor inside operates at high speed and under heavy load for extended periods. The coaxiality between the rotor and the drive shaft system directly affects the smooth operation of the entire unit. Poor alignment can cause severe vibration, accelerate bearing wear, and even lead to unplanned equipment shutdowns. During equipment installation and routine maintenance, high-precision coaxiality correction of the rotor shaft system is essential. This is a fundamental prerequisite for ensuring continuous and stable operation of the entire process.

[0003] Currently, industrial sites mostly use dial indicators or conventional laser alignment instruments for mechanical alignment. These methods primarily extract the geometric dimensional deviations of the coupling's outer diameter and end face in a cold, stopped state. Existing cold alignment techniques have very mature operational procedures. Maintenance personnel can directly obtain the parallelism and angular deviations displayed on the measuring device screen. This process can complete static data acquisition at a relatively low implementation cost. After measurement and adjustment, the geometric axes of the two rotor sections can achieve a high degree of overlap in a stationary state.

[0004] Existing calibration processes exhibit certain logical inconsistencies during actual load operation. After the unit starts operating, the casing expands due to heat, causing spatial deformation. The hydrodynamic oil film built up inside the bearings lifts the rotor journals upwards. Due to the combined effects of thermal displacement, the actual operating shaft center deviates from its original stopping position. Existing methods typically use cold-state geometric alignment as the primary adjustment target. This static calibration target lacks a reverse compensation mechanism for dynamic offsets during operation; after startup, the originally aligned shafts may experience additional off-center loads. In the base adjustment stage, the theoretically calculated lifting amount often contains irregular decimals. On-site shims are mostly standard parts with fixed thickness specifications. Construction workers habitually use simple rounding to directly stack the shims. The rounding errors at each base support point are randomly distributed. This coarse combination of discrete thicknesses easily leads to inadequate local support. When tightening the anchor bolts, the residual thickness deviation is forcibly converted into assembly stress and applied to the casing. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for correcting the coaxiality of a rotor for a booster compressor. This method solves the problems of conventional static cold-state alignment, which is difficult to adapt to dynamic shaft offset caused by thermal expansion and oil film rise after equipment operation, and the problem that the rough assembly of shims on site can easily lead to local insufficiency and cause additional assembly stress on the unit.

[0006] To achieve the above objectives, the present invention provides a method for correcting the coaxiality of a rotor for a booster compressor, comprising the following steps: A global measurement coordinate system is established using a three-dimensional laser measurement device, and the initial misalignment is obtained to perform cold-state safety initial alignment; After the unit reaches thermally stable operating conditions, the DC gap voltage data of the eddy current displacement probe is acquired using the data acquisition unit, and the DC gap voltage data is converted into unidirectional radial displacement. A projection relationship matrix is ​​constructed using a data processing terminal. The unidirectional radial displacement is then calculated by coordinate transformation using the projection relationship matrix to obtain the actual thermal center displacement vector in the global measurement coordinate system. Based on the actual hot-state center displacement vector, spatial axis extrapolation calculation is performed to obtain the hot-state center offset vector and hot-state angular misalignment at the coupling end face; Based on the hot-state center offset vector and the hot-state angle misalignment, perform cold-state pre-bias compensation calculation to generate correction target parameters; Based on the corrected target parameters, perform gasket combination optimization calculations and output the gasket combination scheme and lateral micro-displacement amount; Adjustments are made based on the aforementioned gasket combination scheme and the lateral micro-displacement operation base adjustment mechanism, and the tolerance is determined by re-measuring using the aforementioned three-dimensional laser measuring device.

[0007] Preferably, the steps of establishing a global measurement coordinate system using a three-dimensional laser measurement device and obtaining the initial misalignment include: Using the cold output axis of the turbine reference shaft system as the geometric alignment reference, the global measurement coordinate system is established. The global measurement coordinate system is an O-XYZ coordinate system, with the Z-axis parallel to the cold output axis of the turbine reference shaft system, the X-axis representing the horizontal radial direction, and the Y-axis representing the vertical diameter direction. Based on the runout data collected by the three-dimensional laser measuring device, the reference axis of the steam turbine and the axis to be corrected of the turbocharger are fitted. Calculate the coordinates of the reference intersection point between the turbine reference axis and the reference reference plane, and calculate the coordinates of the intersection point between the turbocharger axis to be corrected and the reference reference plane. Calculate the parallel misalignment amount based on the deviation between the reference intersection coordinates and the intersection coordinates to be corrected; The spatial angular misalignment is calculated based on the angle between the turbine reference axis and the turbocharger axis to be corrected on the XZ horizontal projection plane, and the angle between the turbine reference axis and the turbocharger axis to be corrected on the YZ vertical projection plane. The parallel misalignment and the spatial angle misalignment are used as the initial misalignment.

[0008] Preferably, the step of converting the DC gap voltage data into a unidirectional radial displacement includes: The data acquisition unit records the initial output voltage of the eddy current displacement probe in the cold shutdown state, and uses the initial output voltage as the cold reference voltage. The data acquisition unit extracts the original voltage signal of the eddy current displacement probe under thermally stable operating conditions, and performs low-pass filtering on the original voltage signal to obtain the hot DC gap voltage. Based on the sensitivity coefficient of the eddy current displacement probe, the difference between the hot DC gap voltage and the cold reference voltage is converted into the unidirectional radial displacement.

[0009] Preferably, the step of performing coordinate transformation calculation on the unidirectional radial displacement includes: Determine the installation angles of two eddy current displacement probes, whose measurement directions are not parallel, relative to the global measurement coordinate system, located within the same bearing node section. Based on the installation angle, a projection relationship matrix reflecting the correspondence between the probe measurement direction and the actual displacement is constructed; Perform an inverse matrix operation on the projection relationship matrix to convert the unidirectional radial displacement into the actual thermal center displacement vector in the global measurement coordinate system.

[0010] Preferably, the steps for obtaining the hot-state center offset vector and the hot-state angular misalignment amount at the coupling end face include: Obtain the actual thermal center displacement vector of the driving end and the actual thermal center displacement vector of the non-driving end; The thermal angular misalignment is calculated based on the difference between the actual thermal center displacement vector of the driving end and the actual thermal center displacement vector of the non-driving end, and the span between the two bearing nodes. The hot center offset vector is obtained by linear extrapolation based on the actual hot center displacement vector of the driving end, the actual hot center displacement vector of the non-driving end, the span between the two bearing nodes, and the axial distance from the center of the driving end bearing to the reference plane.

[0011] Preferably, the step of performing cold-state pre-bias compensation calculation to generate the corrected target parameters includes: The new corrected target point is obtained by subtracting the thermal center offset vector from the coordinates of the reference intersection point on the reference reference plane. The hot-state angular misalignment is decomposed into hot-state horizontal angle increment and hot-state vertical angle increment. Based on the angle between the turbine reference axis and the turbocharger axis to be corrected on the XZ horizontal projection plane, the angle between the turbine reference axis and the turbocharger axis to be corrected on the YZ vertical projection plane, the hot-state horizontal angle increment, and the hot-state vertical angle increment, the corrected target angle is calculated. The newly corrected target point and the corrected target angle are used as the corrected target parameters.

[0012] Preferably, before performing the gasket combination optimization calculation, the following steps are also included: Extract the axial distance from the end face of the coupling to each base support point and the lateral span between the base support points; Based on the newly corrected target point, the corrected target angle, the axial distance, and the lateral span, the theoretically continuous adjustment thickness required for each base support point to achieve the corrected target is calculated using rigid body geometric transformation relationships.

[0013] Preferably, the steps for performing gasket combination optimization calculations and outputting gasket combination schemes include: Establish a calculation relationship with the objective of minimizing the difference between the actual gasket assembly thickness and the target total thickness; Based on the standard shim thickness specifications available on site, determine the combination of shims that minimizes the adjustment error of each base support point. Calculate the thickness cutoff error at each base support point, and adjust the residual torque balance of the torque trend caused by the thickness cutoff error. Combine the adjusted number of gaskets as the gasket combination scheme.

[0014] Preferably, the step of outputting the lateral micro-displacement includes: The lateral micro-displacement used to adjust the horizontal position of the base is calculated based on the coordinate difference in the horizontal radial direction between the newly corrected target point and the current intersection point to be corrected.

[0015] Preferably, the step of re-measuring using the three-dimensional laser measuring device to determine tolerance includes: The coordinates of the current intersection point to be corrected and the current integrated spatial angle are obtained by re-measuring; Calculate the geometric distance residual based on the current intersection point coordinates to be corrected and the new corrected target point in the corrected target parameters, and calculate the angle residual based on the current integrated spatial angle and the corrected target angle in the corrected target parameters; Determine whether the geometric distance residual exceeds the preset displacement tolerance, and determine whether the angle residual exceeds the preset angle tolerance; If the geometric distance residual does not exceed the preset displacement tolerance and the angle residual does not exceed the preset angle tolerance, then the centering result is output as qualified. If the geometric distance residual exceeds the preset displacement tolerance, or the angle residual exceeds the preset angle tolerance, and the current number of adjustments does not exceed the maximum number of iterations threshold, then the current intersection coordinates to be corrected and the current comprehensive spatial angle are used as new inputs to regenerate the gasket combination scheme and the lateral micro-displacement. If the geometric distance residual exceeds the preset displacement tolerance, or the angle residual exceeds the preset angle tolerance, and the current number of adjustments exceeds the maximum number of iterations threshold, then the adjustment will be stopped and an error message will be output.

[0016] This invention provides a method for correcting the coaxiality of a rotor used in a booster compressor. It offers the following advantages: 1. This invention employs a technical solution that uses a projection relationship matrix to perform coordinate transformation calculations on the gap voltage of eddy current displacement probes whose measurement directions are not parallel, accurately calculating the actual thermal center displacement vector in the global measurement coordinate system. Compared to existing technologies that rely solely on obtaining surface geometric deviations during shutdown and dial indicator operation, this invention overcomes the shortcomings of conventional alignment processes in monitoring the dynamic displacement of the shaft center caused by thermal expansion of the unit and oil film rise.

[0017] 2. This invention employs a technical solution that uses the hot-state offset obtained through spatial extrapolation to reconstruct and correct the target parameters by introducing it back into the cold-state reference. This allows the turbocharger rotor to utilize a preset cold-state offset to offset the hot-state operational offset after entering thermally stable operating conditions, thus achieving a coaxial state. Compared to existing technologies that consistently use the zero cold-state position deviation as the final assembly alignment target, this method overcomes the deficiency of additional off-center loads that still occur when the machine is mechanically aligned during shutdown but under load.

[0018] 3. This invention employs a technical solution based on minimizing the difference in shim thickness, combined with residual torque balance adjustment to output a discrete combination strategy. This process converts theoretically continuous thickness values ​​into a more stable, field-executable process adjustment table. Compared to existing technologies that rely on personnel experience to simply round and sum shim dimensions, this invention solves the problems of localized insufficiency and stress accumulation in the housing caused by concentrated rounding errors in the adjustment components. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the system architecture of the present invention; Figure 2 This is a schematic diagram of the method flow of the present invention; Figure 3This is a flowchart illustrating the principle of constructing the cold-state measurement coordinate system and obtaining the initial misalignment of the present invention. Figure 4 This is a flowchart illustrating the principle of thermally stable DC gap data acquisition and displacement conversion of the present invention. Figure 5 This is a flowchart illustrating the principle of probe angle arrangement displacement calculation and coordinate transformation in this invention. Figure 6 This is a flowchart illustrating the principle of extrapolation calculation for the thermal offset of the spatial axis in this invention. Figure 7 This is a flowchart illustrating the cold-state pre-bias compensation calculation principle of the present invention. Figure 8 This is a flowchart illustrating the calculation principle of the base pad assembly of the present invention; Figure 9 This is a flowchart of the calibration execution and closed-loop verification process of the present invention; Figure 10 This is a comparison chart of the runout data of the unit before and after calibration according to the present invention, where (a) represents the radial and end face runout curves before the initial cold calibration, and (b) represents the radial and end face runout curves after the final retest is qualified. Figure 11 This is a diagram showing the extrapolated trajectory of the thermal center offset vector and the pre-biased target point of the present invention. Figure 12 This is a diagram showing the distribution of adjustment amount of the base support shim and the balance of residual torque in this invention. Detailed Implementation

[0020] The technical solutions in 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.

[0021] Reference Figure 1 This invention provides a method for correcting the coaxiality of a rotor for a turbocharger. The system for performing this method includes a turbine reference shaft system, a turbocharger shaft system to be corrected, a three-dimensional laser measuring device, an eddy current displacement probe, a data acquisition unit, a data processing terminal, and a base adjustment mechanism.

[0022] The turbine reference shaft system serves as a geometric alignment reference, providing the reference axis for establishing the global measurement coordinate system. The turbine reference shaft system includes the output shaft and the corresponding support bearing structure; its cold-state output shaft direction is used to determine the principal axis direction of the global measurement coordinate system.

[0023] The booster compressor shaft system to be calibrated is the shaft system to be calibrated in this process. The booster compressor shaft system to be calibrated is in a state of pending connection, temporary connection or preliminary connection with the turbine reference shaft system through a coupling, and is formally connected or tightened after the cold safety initial alignment is completed; under hot operating conditions, the booster compressor shaft system to be calibrated will experience shaft center misalignment caused by thermal expansion and oil film buoyancy.

[0024] The three-dimensional laser measuring device is positioned at an external measurement location on the unit. The measuring optical path is aligned with the coupling end face, the surface of adjacent journals, or a measuring target set on the coupling end face or the surface of adjacent journals. The three-dimensional laser measuring device acquires radial runout data and end face runout data under low-speed turning conditions, and fits the axis and reference plane based on the acquired data to output the cold-state shaft system geometric parameters.

[0025] Eddy current displacement probes are fixedly installed inside the support bearing housings of the shaft system to be calibrated in the booster compressor. Within the same bearing node section, at least two eddy current displacement probes have non-parallel measurement directions to monitor the change in clearance between the journal and the bearing housing during rotor operation in real time and output the corresponding clearance voltage signal.

[0026] The data acquisition unit is communicatively connected to the eddy current displacement probe. The data acquisition unit acquires and records the DC gap voltage signal under both cold shutdown and thermally stable operating conditions, and filters the raw voltage signal to obtain the DC gap voltage component used for displacement calculation.

[0027] The data processing terminal receives data transmitted from the 3D laser measurement device and the data acquisition unit. Based on the probe installation angle, DC gap voltage variation, reference plane parameters, and base geometric parameters, the data processing terminal performs coordinate transformation calculations, cold-state pre-offset compensation calculations, and shim combination optimization calculations. In one embodiment, the inputs to the data processing terminal include at least: probe installation angle, cold-state reference voltage, hot-state DC gap voltage, coupling end face position, bearing node span, base support point position, and shim thickness specifications; its output includes at least: hot-state center offset in the global measurement coordinate system, correction target parameters, shim combination schemes for each support point, and lateral micro-displacement.

[0028] The base adjustment mechanism is located at the bottom support interface of the booster compressor's shaft system to be calibrated. The base adjustment mechanism includes anchor bolts, adjusting shims, and a combination of stainless steel shims with standard discrete thicknesses. It may also include lateral adjusting bolts, set screws, or positioning adjustment components for slightly moving the base horizontally. Based on the shim combination scheme and lateral micro-movement amount output from the data processing terminal, the base adjustment mechanism adjusts the vertical position, horizontal position, and axial tilt of the booster compressor's shaft system to be calibrated.

[0029] Reference Figure 2To illustrate the coordination relationship between the aforementioned execution units during the coaxiality correction process, the basic steps of this process method are first given below; the specific measurement, calculation, and adjustment processes for each step will be further explained later in conjunction with the corresponding accompanying drawings. This invention provides a process method for coaxiality correction of a rotor for a booster compressor, comprising the following steps: S100 uses a three-dimensional laser measuring device to establish a global measurement coordinate system and obtain the initial misalignment, and performs cold-state safety initial alignment accordingly; S200, after the unit reaches thermally stable operating conditions, uses the data acquisition unit to acquire the DC gap voltage data of the eddy current displacement probe and converts it into unidirectional radial displacement. S300 uses a data processing terminal to construct a projection relationship matrix, performs coordinate transformation calculation on the unidirectional radial displacement, and obtains the actual thermal center displacement vector in the global measurement coordinate system. S400, based on the actual hot-state center displacement vector, performs spatial axis extrapolation calculation to obtain the hot-state center offset vector and hot-state angular misalignment at the coupling end face; S500 incorporates the hot-state center offset vector and the hot-state angular misalignment into the cold-state alignment calculation relationship, performs cold-state pre-offset compensation calculation, and generates the correction target parameters. S600 will correct the target parameters input to the base adjustment calculation relationship, perform gasket combination optimization calculation, and output the gasket combination scheme and lateral micro-displacement. The S700 is based on a shim combination scheme and a lateral micro-displacement operation base adjustment mechanism, and uses a three-dimensional laser measurement device to re-measure and verify the intersection coordinates and angle parameters.

[0030] The following will provide a detailed explanation of each specific step of the above correction process method in conjunction with the execution units of the system.

[0031] Reference Figure 3 This embodiment is used to illustrate the implementation method of the initial alignment stage of cold safety, that is, firstly, a global measurement coordinate system is established with the turbine side axis, then the relative position of the turbine reference axis and the turbocharger axis to be corrected is obtained, and the initial misalignment is calculated and mechanical coarse alignment is completed accordingly.

[0032] S110, Establish the global measurement coordinate system and reference datum plane.

[0033] Using the cold output shaft of the turbine reference shaft system as the geometric alignment reference, geometric measurement data of the turbine output shaft, coupling end face or corresponding measurement target are collected by a three-dimensional laser measurement device to establish a Cartesian three-dimensional measurement coordinate system O-XYZ.

[0034] In this global measurement coordinate system, the Z-axis is parallel to the cold output axis of the turbine reference shaft system, the X-axis represents the horizontal radial direction, and the Y-axis represents the vertical diameter direction. The coordinate origin O can be selected at the center of the turbine-side coupling end face, the intersection of the turbine output axis and the coupling end face, or a fixed measurement reference point that facilitates repeated on-site measurements.

[0035] As a preferred approach, the plane containing the coupling end face at the output end of the turbine reference shaft system, or a virtual plane determined by the turbine output shaft and the coupling mounting interface, is selected as the reference reference plane. Reference plane This is used to uniformly represent subsequent axis intersections, parallel misalignment, and thermal offset, avoiding errors caused by direct comparison between different measurement sections.

[0036] S120 collects cold-state vibration data and performs spatial axis fitting calculations.

[0037] With the unit cold-shutdown and unloaded, connect and operate the mechanical turning device to bring the turbine reference shaft system and the turbocharger shaft system to be corrected into a low-speed turning state. During low-speed turning, the three-dimensional laser measuring device samples the coupling end face, adjacent journal surface, or measuring target at a preset phase angle to collect radial runout data and end face runout data.

[0038] The aforementioned phase angle can be determined based on the accuracy of the on-site measurement, for example, by using a step angle of 45 degrees or less to ensure that the sampling points cover the entire rotation cycle. Each set of sampling data must include at least the spatial coordinates of the measuring point in the global measurement coordinate system and the corresponding rotation phase.

[0039] Based on the collected discrete spatial point set, the least squares method is used to fit the turbine reference axis and the turbocharger axis to be corrected, respectively. Specifically, assuming the axis to be fitted is a spatial straight line, the direction vector of the corresponding axis and the coordinates of a point on the axis are obtained by finding the straight line parameters that minimize the sum of the squares of the normal distances from each measurement point to this spatial straight line. Thus, the turbine reference axis is obtained. With the axis to be corrected of the booster compressor .

[0040] Subsequently, the turbine reference axis was calculated. With reference plane The intersection point is recorded as the reference intersection point. ,in The coordinate components of the reference intersection point on the X-axis. The coordinate components of the reference intersection point on the Y-axis are used to calculate the axis of the booster compressor to be corrected. With reference plane The intersection point is recorded as the intersection point to be corrected. ,in Let X be the coordinate components of the intersection point to be corrected on the X-axis. The coordinate components of the intersection point to be corrected on the Y-axis.

[0041] S130, calculate the initial misalignment and perform mechanical initial alignment.

[0042] Cold-state misalignment of the unit includes parallel misalignment within the reference plane and spatial angular misalignment. Based on the reference intersection point... Intersection with the point to be corrected Calculate the axis of the booster compressor to be corrected. Relative to the turbine reference axis Parallel misalignment in cold state : ; in, Indicates the axis of the booster compressor to be corrected. Relative to the turbine reference axis In the reference plane The magnitude of the overall radial translation deviation.

[0043] Subsequently, the spatial angular misalignment in the cold state was calculated. : ; in, Indicates the reference axis of the steam turbine With the axis to be corrected of the booster compressor The angle between the projections on the XZ horizontal plane; Indicates the reference axis of the steam turbine With the axis to be corrected of the booster compressor The angle of projection on the vertical plane YZ; It represents the combined deflection angle of the two central axes in three-dimensional space.

[0044] On-site personnel based on parallel misalignment measurement Spatial angle misalignment The support base of the booster compressor's shaft system to be aligned is mechanically roughly aligned. Mechanical rough alignment includes changing the vertical height of the base by using stainless steel shims or adjusting shims, changing the horizontal position of the base by using lateral adjusting bolts, set screws or positioning adjustment parts, and fixing the adjusted base position by tightening the anchor bolts.

[0045] During the adjustment process, the cold-state allowable tolerance is used as the basis for judgment. The cold-state allowable tolerance can be provided by the equipment manufacturer or determined based on the coupling type, unit speed rating, and rotating machinery installation specifications. Once both the parallel misalignment and the spatial angular misalignment meet the cold-state allowable tolerance, low-speed turning gear operation is initiated for verification.

[0046] If no mechanical friction, abnormal resistance, or obvious jamming occurs during the low-speed turning process, the initial cold-state safety alignment is completed, and the initial alignment state required for subsequent trial operation is formed.

[0047] Reference Figure 4 This embodiment illustrates how to collect the DC gap voltage of the eddy current displacement probe after the unit reaches thermally stable operating conditions, and how to convert the voltage change into the unidirectional radial displacement of the rotor journal in the probe measurement direction.

[0048] S210 determines the thermally stable operating condition and extracts the original gap voltage signal.

[0049] After the unit completes its initial cold-state safety alignment, it undergoes no-load and low-load trial runs sequentially according to the operating procedures, gradually increasing to the rated load or a safe and stable operating condition. During this process, the operating load, bearing housing temperature, and lubricating oil temperature are used to determine whether the unit has entered a thermally stable operating condition.

[0050] As a preferred method, when the operating load of the booster compressor's shaft system to be calibrated reaches the rated load or a safe and stable operating condition, and the temperature change rate of each support bearing housing and the system lubricating oil within a preset time period is lower than a set threshold, the unit is determined to have entered a thermally stable operating condition. The aforementioned preset time period and set threshold can be determined based on the equipment manufacturer's documents, on-site commissioning procedures, or operating experience. For example, the preset time period may be two hours, and the temperature change rate threshold may be 1 degree Celsius per hour.

[0051] Before extracting hot-state data, a cold-state comparison benchmark is established. Specifically, when the unit is cold-state shut down and no dynamic oil film has formed, the initial output voltage of the eddy current displacement probes located at each bearing node of the turbocharger shaft to be calibrated is recorded by the data acquisition unit and used as the cold-state benchmark voltage. Once the unit enters a thermally stable operating condition, the data acquisition unit again acquires the operating voltage of the corresponding probe channel. The aforementioned bearing nodes include drive-end nodes and non-drive-end nodes; in actual layout, other support nodes that can reflect changes in rotor journal position can also be selected based on the unit structure.

[0052] It should be noted that the eddy current displacement probe collects the thermal center offset of the rotor journal relative to the bearing housing. For the overall thermal expansion of the support, housing, or base relative to the foundation, the thermal expansion parameters provided by the manufacturer, the calculated temperature of the bearing housing, or data from external measurement points can be input as additional compensation values ​​into the data processing terminal, and used together with the eddy current displacement data in subsequent compensation calculations.

[0053] S220, extracts the DC gap voltage component.

[0054] During unit operation, the raw voltage signal output by the eddy current displacement probe typically contains both DC and AC components. The AC component primarily reflects the rotor's vibration response, while the DC component primarily reflects the change in clearance between the probe end face and the journal surface. This process method uses the DC component to characterize the change in the hot-state center position of the rotor journal relative to the bearing housing.

[0055] The data acquisition unit performs low-pass filtering on the raw voltage signal to reduce the impact of the rotor fundamental frequency and its higher harmonics on the extracted DC gap voltage. The cutoff frequency of the low-pass filter is determined based on the fundamental frequency corresponding to the unit's rated speed, and its value is lower than that fundamental frequency to preserve the slow variable components of the gap voltage.

[0056] To further reduce the impact of random noise, the filtered data over multiple rotation cycles can be averaged using the key phase signal or other phase reference signals. After filtering and averaging, the hot DC gap voltage used for displacement conversion is obtained.

[0057] S230 converts the DC gap voltage difference into a unidirectional radial displacement.

[0058] Within its effective linear range, the output voltage of an eddy current displacement probe exhibits an approximately linear relationship with the distance from the probe end face to the metal surface being measured. Therefore, provided that the probe mounting gap does not exceed the linear range during both cold and hot operation, the DC gap voltage difference can be converted into a unidirectional radial displacement based on the probe sensitivity coefficient.

[0059] Assume eddy current displacement probes are arranged at the same bearing node. And eddy current displacement probe The cold-state reference DC voltages measured under cold-state shutdown conditions are as follows: and The hot DC gap voltages extracted under thermally stable operating conditions are respectively and The unidirectional radial displacement can then be calculated using the following formula: ; ; in, This is the calibration sensitivity coefficient of the eddy current displacement probe; Indicating rotor journal displacement along eddy current probe The unidirectional radial displacement generated in the measurement direction; Indicating rotor journal displacement along eddy current probe The unidirectional radial displacement generated in the measurement direction.

[0060] The positive and negative directions of the aforementioned unidirectional radial displacement are determined according to the field calibration direction of the eddy current displacement probe. When the voltage change direction of a certain probe channel is opposite to the agreed positive displacement direction, the data processing terminal corrects the sign of the calculation results according to the calibration direction coefficient of the probe channel whose voltage change direction is opposite to the agreed positive displacement direction.

[0061] The data acquisition unit will calculate the results. and Displacement vectors in the direction of probe measurement : ; in, This represents the displacement vector in the direction measured by the probe. This indicates the matrix transpose.

[0062] This displacement vector serves as the input for subsequent coordinate transformation calculations, converting the unidirectional radial displacement measured by eddy current displacement probes with non-parallel measurement directions into the thermal center displacement in the global measurement coordinate system.

[0063] Reference Figure 5 This embodiment illustrates how, after obtaining the unidirectional radial displacement in the probe's measurement direction, a projection relationship is established based on the installation angle of the eddy current displacement probe, and the displacement is converted into a thermal center displacement vector in the global measurement coordinate system.

[0064] S310 defines the probe installation angle.

[0065] Due to limitations imposed by the internal mounting space of the bearing housing, the location of the probe mounting holes, and the bearing structure, two eddy current displacement probes arranged within the same bearing node section do not necessarily need to be installed horizontally or vertically. Therefore, before performing coordinate transformation, it is necessary to determine the installation angles of the measurement directions of the two eddy current displacement probes relative to the global measurement coordinate system.

[0066] Assume an eddy current displacement probe within the same bearing node cross section. And eddy current displacement probe The installation angles of its measurement axis relative to the positive X-axis of the global measurement coordinate system are respectively and The aforementioned installation angles are measured with the positive X-axis as the starting direction and according to the same rotation direction; preferably, the counterclockwise direction is used as the positive direction.

[0067] Installation angle and The values ​​can be obtained from the bearing housing design drawings and probe mounting hole machining drawings, or they can be calibrated on-site using angle measuring tools during the cold installation phase and then input into the data processing terminal. To ensure that the subsequent calculation results are consistent with the actual measurement direction, the angle definitions, positive displacement directions, and the aforementioned voltage change sign correction rules for the two probes should all adopt the same coordinate direction convention.

[0068] S320 establishes the projection relationship between the actual displacement and the probe measurement direction.

[0069] After the unit enters the thermally stable operating condition, the rotor journal experiences a thermal center shift due to thermal expansion and oil film buoyancy. The unidirectional radial displacement measured by the eddy current displacement probe is not the direct displacement of the rotor journal in the X and Y axis directions, but rather the projected component of this thermal center shift along the corresponding probe measurement direction.

[0070] Let the actual thermal center displacement vector of the rotor journal in the global measurement coordinate system be... ,in This represents the horizontal thermal displacement component of the rotor shaft center along the X-axis. This represents the vertical thermal displacement component of the rotor shaft center along the Y-axis. Based on the planar projection relationship, the data processing terminal establishes the actual thermal center displacement vector. displacement vector relative to the probe measurement direction Projection relationship matrix between : ; Expanding the above vector expression into a specific matrix formula is as follows: ; In this matrix, the trigonometric function terms represent the projection ratios of each probe's measurement direction onto the X and Y axes of the global measurement coordinate system. This projection relationship allows for the establishment of a correspondence between the one-dimensional measurement results of two non-parallel eddy current displacement probes and the two-dimensional thermal center displacement of the rotor journal in the global measurement coordinate system.

[0071] S330, perform inverse matrix calculation to obtain the thermal center displacement vector.

[0072] To obtain the thermal center displacement vector in the global measurement coordinate system, the data processing terminal projects the relationship matrix. Perform inverse matrix operations. From the computational perspective, the projection relation matrix... The prerequisite for invertibility is that its determinant is not zero, that is: .

[0073] In other words, the measurement directions of the eddy current displacement probe u and the eddy current displacement probe v cannot be parallel to each other. If the angle between the two probes is too small, the original measurement error will be amplified when the matrix is ​​inverted, affecting the accuracy of the calculation of the hot center displacement.

[0074] As a preferred embodiment, the included angle between the measurement axes of the two eddy current displacement probes is set to 60 to 120 degrees to ensure good computational stability of the projection relationship matrix. When the above conditions are met, the data processing terminal calculates the actual thermal center displacement vector of the rotor journal in the global measurement coordinate system using the following formula. : ; The corresponding algebraic expansion is: ; Therefore, the unidirectional radial displacement in different probe measurement directions is converted into horizontal thermal displacement components in the global measurement coordinate system. and vertical thermal displacement components The actual hot-state center displacement vector is used for subsequent spatial axis extrapolation calculations and serves as input data for calculating the hot-state center offset at the coupling end face.

[0075] Reference Figure 6 This embodiment illustrates how, after obtaining the actual hot-state center displacement vectors of the driving end and the non-driving end, the hot-state angular misalignment is calculated based on the axial distance between the two bearing nodes, and the hot-state center displacement is extrapolated to the reference datum plane where the coupling end face is located.

[0076] S410, calculates the thermal angular misalignment of the space axis.

[0077] The turbocharger rotor typically exhibits high rigidity between the two supporting bearing nodes. Without considering significant nonlinear deflection of the rotor due to its own weight, thermal stress, or other factors, the line connecting the axes of the drive-end bearing node and the non-drive-end bearing node can be approximated as a straight line in space.

[0078] The data processing terminal reads the actual hot-state center displacement vectors of the booster compressor's drive end and non-drive end, respectively. Specifically, the data processing terminal performs the aforementioned coordinate transformation calculations on the probe data from the booster compressor's drive end and non-drive end to obtain the actual hot-state center displacement vector of the drive end. and the actual thermal center displacement vector of the non-driving end. .

[0079] To unify the positive and negative directions in extrapolation calculations, this embodiment uses the positive Z-axis of the global measurement coordinate system as the axial reference direction, and sets the axial node sequence as: non-driving end, driving end, reference datum plane. If the actual layout of the field equipment is opposite to the above sequence, the positive Z-axis direction is redefined according to the same principle, or the corresponding axial distance is given the opposite sign.

[0080] span between two bearing nodes The values ​​can be obtained from the markings on mechanical drawings or through on-site measurements. The data processing terminal uses the difference in thermal center displacement between the driving and non-driving ends, as well as the span between the two bearing nodes, to determine the optimal values. Calculate the hot-state angular misalignment of the booster compressor's shaft under adjustment from a cold state to a stable hot operating condition. This hot-state angular misalignment includes the increase in the horizontal angle. Increment of the vertical angle The calculation formula is: ; ; Among them, the horizontal angle increment This represents the angular change of the rotor's hot-state axis relative to its cold-state position in the XZ plane; the vertical angle increment. This represents the angular change of the rotor's hot-state axis relative to its cold-state position in the YZ plane. The ratio of the displacement difference to the bearing node span represents the axis slope in the corresponding projection plane, and the corresponding angular increment is obtained through arctangent calculation.

[0081] S420, calculate the thermal center offset vector at the end face of the coupling.

[0082] In the alignment of a booster compressor, the plane containing the coupling end face is usually used as a reference position for evaluating alignment errors and subsequent adjustments. Since the eddy current displacement probe is located at the bearing node, it cannot directly measure the hot position of the shaft center at the end face of the rotating coupling. Therefore, it is necessary to extrapolate the hot center displacement of the driving end and the non-driving end to the reference plane.

[0083] Under the aforementioned spatial linear approximation conditions, the hot axis of the booster compressor can be extrapolated linearly in both the XZ and YZ planes. The data processing terminal then uses the actual hot center displacement vector of the drive end... The actual thermal center displacement vector of the non-driving end Span between two bearing nodes and the axial distance from the center of the drive end bearing to the reference datum plane Calculate the thermal center offset vector at the end face of the coupling. The extrapolation calculation formula is as follows: ; in, and These represent the displacement components of the thermal center offset vector on the X and Y axes of the global measurement coordinate system, respectively. This indicates the axial distance from the center of the drive end bearing of the shaft system to be corrected in the booster compressor to the reference datum plane.

[0084] Through the above calculations, the hot center displacement data obtained at the bearing node is converted into a hot center offset vector at the reference plane. This hot center offset vector is used for subsequent cold pre-offset compensation calculations to determine the target position to be approximated for the intersection point to be corrected during the secondary alignment after shutdown.

[0085] Reference Figure 7 This embodiment illustrates how, after obtaining the hot-state center offset vector and hot-state angular misalignment amount at the coupling end face, the hot-state operating offset is converted into the cold-state pre-offset target required for secondary alignment after shutdown.

[0086] S510, establishes a cold-state pre-bias compensation method for operational offset.

[0087] When industrial rotating machinery transitions from a cold shutdown state to a thermally stable operating state, the rotor shaft position may shift due to factors such as thermal expansion of the casing and support system, and dynamic pressure rise of the bearing lubricating oil film.

[0088] When there is a measurable or predictable shaft center offset in the turbine reference shaft system during hot operation, the data processing terminal synchronously collects or inputs the hot center offset on the turbine side, and uses the relative offset obtained by subtracting the hot center offset on the turbine side from the hot center offset on the turbocharger side as the basis for compensation.

[0089] When the hot offset on the turbine side is negligible, or has been pre-compensated by the cold alignment value given by the manufacturer, the cold output axis of the turbine reference shaft system shall be used as the geometric alignment reference.

[0090] If the turbocharger shaft system to be corrected and the turbine reference shaft system are only adjusted to an ideal coaxial state under cold conditions, thermal expansion and oil film rise may still cause additional misalignment effects on the shaft system after the unit enters thermally stable operating conditions. To reduce this effect, this embodiment adopts a cold-state pre-offset compensation method.

[0091] This cold-state pre-offset compensation method is based on the repeatability of the unit's hot-state center offset. Specifically, the data processing terminal introduces the calculated hot-state center offset and hot-state angular misalignment into the cold-state alignment target, ensuring that the turbocharger shaft system to be corrected reserves a displacement and angle opposite to the hot-state operating offset direction when the unit is shut down in a cold state. After the unit resumes operation to a thermally stable condition, this reserved amount is offset by the actual hot-state offset, causing the turbocharger shaft system to be corrected and the turbine reference shaft system to tend to be coaxial under operating conditions.

[0092] S520, reconstruct and correct the target intersection point and target angle parameters.

[0093] The data processing terminal will offset the thermal center offset vector at the coupling end face. And the amount of thermal angle misalignment , The corrected target parameters are generated from the input cold-state alignment calculation relationship and used during the secondary shutdown alignment.

[0094] First, based on the initial datum intersection point on the reference datum plane The new corrected target point with cold pre-bias is obtained by vector subtraction calculation. The corresponding reconstructed mathematical expression is: ; in, Represents the original reference intersection vector; and These represent the target coordinates of the newly corrected target point on the X and Y axes of the global measurement coordinate system, respectively; the minus sign in the formula indicates that the pre-offset direction is opposite to the hot-state center offset direction, that is, the expected hot-state center offset is deducted from the cold-state aligning target.

[0095] Secondly, the data processing terminal calculates the corrected target angle based on the initial cold projection angle and the incremental hot projection angle. To ensure the correct direction of angle compensation, , , and The same sign convention is used. The spatial angle compensation equation is set as follows: ; in, and These are the angles between the projections of the turbine reference axis and the compressor axis to be corrected on the XZ and YZ planes, respectively, during the initial cold state. and These represent the incremental increases in the horizontal and vertical angles obtained earlier. By compensating for the angles in the two projection directions and then calculating the combined target angle, the target angle parameters used for secondary alignment can be obtained.

[0096] After completing the above calculations, the data processing terminal will re-correct the target point. and target angle This serves as the geometric reference for subsequent base adjustments. Therefore, in the secondary shutdown and calibration operation, the alignment target is "to make the intersection point to be calibrated..." Intersection with the original reference point "Overlap" should be changed to "Make the intersection points to be corrected" Enter the newly revised target point Within the allowable tolerance range, while ensuring the axis angle meets the target angle. "Permissible tolerances".

[0097] Through the above processing, the cold-state alignment target is converted into a pre-biased target that includes the hot-state operating offset compensation, providing input parameters for subsequent shim combination calculations and lateral micro-displacement calculations.

[0098] Reference Figure 8 This embodiment is used to illustrate the process of obtaining a new corrected target point. and target angle Then, how to convert the geometric alignment target into the shim adjustment amount and lateral micro-movement amount at the base support point, and form an executable process adjustment table according to the shim specifications on site.

[0099] S610, calculates the theoretical adjustment amount of the base fulcrum.

[0100] Obtain the new corrected target point that includes the cold pre-bias. and the corrected target angle Then, the target axis position and angle need to be converted into actual adjustment amounts on the base support interface. Based on the structural dimensions of the compressor shaft system to be corrected, the data processing terminal extracts the axial distance from the coupling end face to each base support point, the lateral span between the base supports points, and the position parameters of each support point in the base coordinate system.

[0101] During the base adjustment process, the positional and angular deviations at the coupling end face are corrected by the height changes and slight horizontal movements of each base support point. Therefore, the data processing terminal corrects the target parameters and inputs the above structural dimensions into the base space adjustment calculation relationship, and calculates the theoretical continuous adjustment thickness required for each base support point to achieve the target pose based on the rigid body geometric transformation relationship. ,in Number the support points of the booster compressor base.

[0102] The theory continuously adjusts the thickness. This indicates the increase or decrease in gasket thickness relative to the current gasket state. A positive value indicates that the gasket thickness needs to be increased, while a negative value indicates that the gasket thickness needs to be decreased.

[0103] As a feasible computational method, let the first... The planar coordinates of each base support point in the base coordinate system are: When making minor adjustments to the base, the theoretical continuous adjustment thickness of the fulcrum can be determined by the overall vertical translation, the lateral tilt angle adjustment, and the longitudinal tilt angle adjustment. The calculation relationship is as follows: ; in, This refers to the overall vertical translation of the base. and These represent the slight tilt angle adjustment of the base around the corresponding direction. and For the first The geometric coordinates of each base fulcrum relative to the base reference origin.

[0104] The data processing terminal adjusts the target point accordingly. Target perspective And the geometric distance from the end face of the coupling to each base support point, solve for , and And obtain the theoretical continuous adjustment thickness of each support point. .

[0105] For horizontal misalignment, the data processing terminal adjusts the target point accordingly. Intersection with the current point to be corrected The coordinate difference between the two points in the X-axis direction is used to calculate the lateral micro-displacement of the base along the horizontal radial direction; this lateral micro-displacement serves as the execution parameter for the lateral adjusting bolt, set screw, or positioning adjustment component.

[0106] S620 establishes a combination calculation relationship based on standard gasket thickness specifications.

[0107] In industrial settings, base height adjustment is typically achieved by adding or removing stainless steel shims of standard thickness. However, shim thickness is a discrete specification and cannot be directly equated to the theoretically continuous adjustment thickness. Therefore, it is necessary to convert the theoretically continuous adjustment thickness into a shim combination scheme that can be implemented on-site.

[0108] As a preferred approach, the data processing terminal pre-records a set of standard gasket thickness specifications available on-site. ,in to These represent single gaskets of different thicknesses. The actual thickness of the gasket assembly at each fulcrum point The composition is as follows: ; in, For the first At the fulcrum, the first Various thickness specifications The specific quantity used, and It is a non-negative integer.

[0109] because It can be a positive or negative value, and the gasket assembly thickness... This indicates the adjusted actual total thickness, and cannot be directly expressed as... As a combined objective. Therefore, the data processing terminal first reads the... The current initial shim thickness at each fulcrum And calculate the adjusted target total thickness: .

[0110] To ensure that the actual shim assembly at each support point is as close as possible to the target total thickness, the data processing terminal establishes a calculation relationship for minimizing the shim assembly error, with the objective of minimizing the overall adjustment error of the base. The objective function is: ; Through this calculation relationship, the data processing terminal selects the combination of shims for each support point within the standard shim specification range, so that the actual adjustment result of each support point is as close as possible to the theoretical adjustment requirement, and reduces the overall centering deviation caused by simply rounding a single support point.

[0111] S630 generates a gasket combination scheme and performs residual torque balance adjustment.

[0112] Data processing terminal according to Given constraints such as non-negative integers and the maximum number of shims stacked at a single support point not exceeding the on-site allowable value, the calculation relationship for minimizing the above shim combination error is solved, and the shim combination scheme for each support point is output.

[0113] Due to limitations imposed by standard gasket thickness specifications, the actual gasket combination thickness is limited. With the target total thickness There may be truncation errors. If the truncation error is concentrated on one side or one corner, it may cause local insufficiency of support, uneven preload, or additional deformation of the casing.

[0114] To mitigate the aforementioned impacts, the data processing terminal performs residual torque balancing adjustments on the truncation errors at each support point. Specifically, the data processing terminal uses the base reference point or the equipment's center of gravity projection point as the torque calculation reference point, calculating the product of the thickness truncation error and the stress arm length for each base support point, and using this product as the equivalent torque trend caused by the truncation error. Under the conditions of satisfying the maximum number of gaskets stacked at a single support point, the minimum gasket thickness specification, and the overall alignment tolerance, the data processing terminal adjusts the number of the thinnest gaskets at at least one base support point. Make fine adjustments to increase or decrease the equivalent torque trends of different base supports so that they cancel each other out or decrease, and make the algebraic sum of the equivalent torques formed by the truncation errors of each support approach zero.

[0115] After the above calculations, the data processing terminal generates the final process adjustment table. This table includes at least the specifications and number of shims to be added or removed at each base support point, the total target shim thickness after adjustment, the allowable residual for the corresponding support point, and the lateral slight displacement of the base in the horizontal direction. This process adjustment table is for on-site personnel to execute in subsequent mechanical adjustment steps.

[0116] Reference Figure 9 This embodiment illustrates how, after adjusting the base shims, fine-tuning the lateral direction, and tightening the bolts according to the process adjustment table, the calibration result is judged to meet the preset tolerance by low-speed rotating the machine for retesting.

[0117] S710, perform base mechanical adjustment.

[0118] After the data processing terminal generates the final process adjustment table, the on-site personnel adjust the base of the booster compressor's shaft system to be corrected according to the process adjustment table. The process adjustment table includes the specifications and number of shims that need to be added or removed at each base support point, the total thickness of the target shims after adjustment, the lateral micro-movement, and the allowable residual for the corresponding support point.

[0119] In specific operations, first confirm the jacking position, support status, and the sequence of loosening the anchor bolts. Then, use hydraulic jacking equipment to smoothly lift the support side of the booster compressor shaft to be corrected, so that an operating gap is formed between the base and the support surface, allowing for the removal or insertion of shims.

[0120] While maintaining stable equipment stress, on-site personnel, following the process adjustment schedule, remove the original shims or insert new standard stainless steel shim combinations at the corresponding fulcrum positions of the base adjustment mechanism. For cases requiring horizontal adjustment, on-site personnel, based on the slight lateral movement, use lateral adjustment bolts, set screws, or positioning adjustment components to make a slight horizontal radial movement of the base of the booster compressor's shaft system to be corrected.

[0121] After the shims are adjusted and the lateral fine-tuning is completed, slowly release the hydraulic lifting equipment to allow the base to re-fit against the support surface, and check whether the shims at each support point are flat, fitted, and not loose.

[0122] To avoid uneven tightening force leading to localized deformation of the casing or introducing additional assembly stress, use a torque wrench to retighten the anchor bolts to the preset torque value. During retightening, a step-by-step tightening method using diagonal and alternating loading can be employed until the specified torque is achieved.

[0123] After the anchor bolts are tightened, record the final shim combination, lateral displacement, and bolt tightening torque at each support point as the basis for the final retest and subsequent inspection and verification.

[0124] S720 performs final retesting and tolerance assessment.

[0125] After the base bolts are tightened, slight compaction or stress release may occur between the base mating surface, the gasket assembly, and the support surface, resulting in a slight change in the shaft position. Therefore, a retest is required after mechanical adjustment to confirm whether the actual alignment meets the correction target requirements.

[0126] After the mechanical re-tightening operation is completed, the turning gear mechanism is connected to put the turbine reference shaft system and the turbocharger shaft system to be corrected into a low-speed turning gear state. Subsequently, the three-dimensional laser measurement device is started to rescan the measurement targets, coupling end faces, or adjacent journal surfaces on the turbine reference shaft system and the turbocharger shaft system to be corrected.

[0127] The data processing terminal calculates the coordinates of the current intersection point to be corrected by using the same global measurement coordinate system and axis fitting method as described above. and from the current comprehensive spatial perspective .

[0128] Subsequently, the data processing terminal compared the current measured results with the newly corrected target point. and the corrected target angle Compare the geometric distance residuals. With angular residual The calculation formula is: ; ; in, This indicates the combined radial deviation of the current intersection point to be corrected relative to the newly corrected target point in the reference plane; This indicates the angular deviation between the current axis angle and the target angle.

[0129] Preset displacement tolerance and preset angle tolerance The specifications can be given by the equipment manufacturer based on the unit speed, coupling type, and coupling allowable compensation capacity, or determined according to applicable rotating machinery installation specifications.

[0130] When satisfied and At that time, the data processing terminal determines that the current alignment status meets the preset tolerance requirements and outputs the alignment result as qualified.

[0131] like or If any of the values ​​exceeds the corresponding threshold, the current adjustment result is deemed unsatisfactory. At this point, the data processing terminal uses the current intersection point to be corrected. and current comprehensive spatial perspective As new calculation inputs, the shim adjustment amount and lateral micro-displacement amount are regenerated, and the next round of mechanical adjustment and retesting is carried out.

[0132] To prevent the calibration process from failing to converge due to pipeline stress, external rigid connections, inadequate base support, or other mechanical interference, a maximum iteration threshold is set on the data processing terminal. If the number of consecutive adjustments and retests exceeds [a certain number]... The data processing terminal stopped continuing the iteration and output an error message, prompting on-site personnel to check for external mechanical interference, pipeline additional load, base support status, or coupling connection status.

[0133] Through the above-mentioned mechanical adjustment, retesting and comparison, and over-limit readjustment process, the intersection point to be corrected can be gradually brought into the allowable tolerance range of the new correction target point, and the coaxiality correction of the booster rotor can be completed.

[0134] To further illustrate the application of the process described in this invention in a steam turbine-driven turbocharger unit, a specific working scenario example is provided below. This example is only used to explain the measurement, compensation, adjustment, and retesting processes of this invention and does not constitute a limitation on equipment model, operating load, rated speed, measured values, or tolerance range.

[0135] This example is based on a multi-shaft centrifugal booster unit driven by a steam turbine in an air separation gas production system. The booster unit is connected to the steam turbine via a diaphragm coupling. This section combines... Figures 10 to 12 The calibration process and data are explained.

[0136] Reference Figure 10 In the initial cold-state shutdown condition, a global measurement coordinate system was established using a three-dimensional laser measuring device with the turbine output axis as the reference, and the plane containing the coupling end face was set as the reference plane. Data collected during low-speed turning showed that the initial parallel misalignment was 0.45 mm and the spatial angular misalignment was 0.12 degrees, exceeding the allowable cold-state tolerance range of the equipment.

[0137] according to Figure 10 The runout distribution shown in section (a) was investigated by performing a cold-state safety initial alignment on-site. By adjusting the base shims and the horizontal position of the base, the parallel misalignment was reduced to 0.08 mm, enabling the unit to meet the conditions for subsequent trial operation.

[0138] The unit was then started and operated under load. When the rate of change of bearing housing temperature and lubricating oil temperature dropped to less than 0.5 degrees Celsius per hour within two hours, the system determined that the unit had entered a thermally stable operating condition. At this time, the data acquisition unit extracted the DC gap voltage component of the eddy current displacement probe at each bearing node and calculated the difference between the hot DC voltage and the cold reference voltage.

[0139] In this example, the installation angles of the eddy current displacement probe were set to 45 degrees and 135 degrees, respectively. The probe voltage sensitivity was 8V / mm, and the data processing terminal used its reciprocal, 0.125mm / V, as the displacement conversion factor to convert the voltage change into a unidirectional radial displacement. Table 1 records the voltage change and displacement conversion results of the probe channel.

[0140] Table 1. Thermal monitoring data and displacement conversion results of eddy current displacement probe: ; Based on the unidirectional radial displacement, probe installation angle, and displacement direction conventions in Table 1, the data processing terminal constructs a projection relationship matrix and performs inverse matrix solving to obtain the actual thermal center displacement vectors of the driving end and non-driving end in the global measurement coordinate system. The span between the two bearing nodes is known to be 1500 mm, and the distance from the center of the driving end bearing to the reference datum plane is 400 mm.

[0141] Reference Figure 11 The figure shows the extrapolation path of the rotor shaft from the driving end and the non-driving end toward the reference plane.

[0142] It should be noted that the eddy current displacement probe obtains the thermal center offset of the rotor journal relative to the bearing housing; for the overall thermal growth of the support, housing or base relative to the foundation, this example uses the bearing housing temperature measurement value or external measurement point data as an additional compensation input to the data processing terminal, and participates in the extrapolation calculation together with the eddy current displacement conversion result.

[0143] After superimposing the above additional compensation amounts, the calculated hot horizontal angle increment is 0.0015 degrees, and the hot vertical angle increment is 0.0032 degrees. Extrapolating to the coupling end face, the components of the hot center offset vector in the X and Y axes are found to be +0.092mm and +0.115mm, respectively. The data processing terminal substitutes this hot center offset amount back into the cold geometric reference to reconstruct a new corrected target point and target angle with cold pre-offset.

[0144] After obtaining the newly corrected target point, the data processing terminal calculates the base adjustment amount. Available stainless steel shim thicknesses on site include 0.05mm, 0.10mm, 0.20mm, 0.50mm, and 1.00mm. Based on the theoretical adjustment amount for each base support point, the initial shim thickness, and the aforementioned shim specifications, the data processing terminal calculates the shim combination scheme for each support point and performs torque balance adjustment on the residuals resulting from rounding the shim specifications.

[0145] Reference Figure 12 , Figure 12The deviation distribution between the theoretical adjustment amount and the actual shim adjustment amount of the four main support points Z1 to Z4 of the base is shown in a combination of scatter plots and bar charts. The specific calculation results are shown in Table 2.

[0146] Table 2. Adjustment scheme and residuals for the shims at each support point of the base: ; In Table 2, a positive theoretical adjustment value indicates that the shim thickness needs to be increased at the corresponding support point, while a negative theoretical adjustment value indicates that the shim thickness needs to be reduced at the corresponding support point. As can be seen from Table 2, the residual difference between the actual adjustment thickness and the theoretical adjustment value at each support point is controlled within ±0.02mm, and the residual distribution at the four support points does not show obvious unilateral concentration after torque balance adjustment.

[0147] On-site personnel operated the base adjustment mechanism according to the shim combination scheme shown in Table 2 and the lateral micro-displacement output from the data processing terminal. After the shim adjustment and lateral micro-adjustment were completed, the anchor bolts were tightened in stages and diagonally using a torque wrench.

[0148] Then, the turning gear mechanism was activated for a final retest, and the fluctuation state of the retest corresponded to... Figure 10 Part (b) of the table. Table 3 lists the comparison of alignment parameters after initial cold alignment, theoretical pre-biased target, and final re-measurement results.

[0149] It should be noted that the theoretical pre-bias target is not a cold-state zero-alignment target, but rather a cold-state reverse compensation target used to offset the hot-state operational deviation. Therefore, the cold-state parallel misalignment under the theoretical pre-bias target may be greater than the misalignment after the initial cold-state alignment.

[0150] Table 3 Comparison of alignment parameters before and after correction: ; According to the data in Table 3, the results of the final remeasurement are basically consistent with the theoretical pre-bias target. Further calculations by the data processing terminal show that the intersection residual of the final remeasurement is 0.01 mm and the angle residual is 0.01 degrees, both within the preset displacement tolerance of 0.05 mm and the preset angle tolerance of 0.02 degrees.

[0151] Therefore, the data processing terminal determined that the current alignment status met the preset tolerance requirements and output a qualified alignment result. The unit then entered continuous production operation, and the bearing vibration index remained within the normal range, indicating that the cold pre-offset correction result could meet the shaft alignment requirements under thermally stable operating conditions.

[0152] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these specific embodiments are merely illustrative. Those skilled in the art can omit, substitute, and modify the details of the above methods and systems in various ways without departing from the principles and essence of the present invention. For example, combining the above method steps to perform substantially the same function and achieve substantially the same result using substantially the same method falls within the scope of the present invention.

Claims

1. A method for correcting the coaxiality of a rotor for a booster compressor, characterized in that, Includes the following steps: A global measurement coordinate system is established using a three-dimensional laser measurement device, and the initial misalignment is obtained to perform cold-state safety initial alignment; After the unit reaches thermally stable operating conditions, the DC gap voltage data of the eddy current displacement probe is acquired using the data acquisition unit, and the DC gap voltage data is converted into unidirectional radial displacement. A projection relationship matrix is ​​constructed using a data processing terminal. The unidirectional radial displacement is then calculated by coordinate transformation using the projection relationship matrix to obtain the actual thermal center displacement vector in the global measurement coordinate system. Based on the actual hot-state center displacement vector, spatial axis extrapolation calculation is performed to obtain the hot-state center offset vector and hot-state angular misalignment at the coupling end face; Based on the hot-state center offset vector and the hot-state angle misalignment, perform cold-state pre-bias compensation calculation to generate correction target parameters; Based on the corrected target parameters, perform gasket combination optimization calculations and output the gasket combination scheme and lateral micro-displacement amount; Adjustments are made based on the aforementioned gasket combination scheme and the lateral micro-displacement operation base adjustment mechanism, and the tolerance is determined by re-measuring using the aforementioned three-dimensional laser measuring device.

2. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 1, characterized in that, The steps for establishing a global measurement coordinate system using a 3D laser measurement device and obtaining the initial misalignment include: Using the cold output axis of the turbine reference shaft system as the geometric alignment reference, the global measurement coordinate system is established. The global measurement coordinate system is an O-XYZ coordinate system, with the Z-axis parallel to the cold output axis of the turbine reference shaft system, the X-axis representing the horizontal radial direction, and the Y-axis representing the vertical diameter direction. Based on the runout data collected by the three-dimensional laser measuring device, the reference axis of the steam turbine and the axis to be corrected of the turbocharger are fitted. Calculate the coordinates of the reference intersection point between the turbine reference axis and the reference reference plane, and calculate the coordinates of the intersection point between the turbocharger axis to be corrected and the reference reference plane. Calculate the parallel misalignment amount based on the deviation between the reference intersection coordinates and the intersection coordinates to be corrected; The spatial angular misalignment is calculated based on the angle between the turbine reference axis and the turbocharger axis to be corrected on the XZ horizontal projection plane, and the angle between the turbine reference axis and the turbocharger axis to be corrected on the YZ vertical projection plane. The parallel misalignment and the spatial angle misalignment are used as the initial misalignment.

3. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 1, characterized in that, The steps for converting the DC gap voltage data into a unidirectional radial displacement include: The data acquisition unit records the initial output voltage of the eddy current displacement probe in the cold shutdown state, and uses the initial output voltage as the cold reference voltage. The data acquisition unit extracts the original voltage signal of the eddy current displacement probe under thermally stable operating conditions, and performs low-pass filtering on the original voltage signal to obtain the hot DC gap voltage. Based on the sensitivity coefficient of the eddy current displacement probe, the difference between the hot DC gap voltage and the cold reference voltage is converted into the unidirectional radial displacement.

4. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 1, characterized in that, The steps for calculating the coordinate transformation of the unidirectional radial displacement include: Determine the installation angles of two eddy current displacement probes, whose measurement directions are not parallel, relative to the global measurement coordinate system, located within the same bearing node section. Based on the installation angle, a projection relationship matrix reflecting the correspondence between the probe measurement direction and the actual displacement is constructed; Perform an inverse matrix operation on the projection relationship matrix to convert the unidirectional radial displacement into the actual thermal center displacement vector in the global measurement coordinate system.

5. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 1, characterized in that, The steps to obtain the hot center offset vector and hot angular misalignment at the coupling end face include: Obtain the actual thermal center displacement vector of the driving end and the actual thermal center displacement vector of the non-driving end; The thermal angular misalignment is calculated based on the difference between the actual thermal center displacement vector of the driving end and the actual thermal center displacement vector of the non-driving end, and the span between the two bearing nodes. The hot center offset vector is obtained by linear extrapolation based on the actual hot center displacement vector of the driving end, the actual hot center displacement vector of the non-driving end, the span between the two bearing nodes, and the axial distance from the center of the driving end bearing to the reference plane.

6. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 2, characterized in that, The steps for performing cold-state pre-bias compensation calculations and generating corrected target parameters include: The new corrected target point is obtained by subtracting the thermal center offset vector from the coordinates of the reference intersection point on the reference reference plane. The hot-state angular misalignment is decomposed into hot-state horizontal angle increment and hot-state vertical angle increment. Based on the angle between the turbine reference axis and the turbocharger axis to be corrected on the XZ horizontal projection plane, the angle between the turbine reference axis and the turbocharger axis to be corrected on the YZ vertical projection plane, the hot-state horizontal angle increment, and the hot-state vertical angle increment, the corrected target angle is calculated. The newly corrected target point and the corrected target angle are used as the corrected target parameters.

7. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 6, characterized in that, Before performing gasket combination optimization calculations, the following steps are also included: Extract the axial distance from the end face of the coupling to each base support point and the lateral span between the base support points; Based on the newly corrected target point, the corrected target angle, the axial distance, and the lateral span, the theoretically continuous adjustment thickness required for each base support point to achieve the corrected target is calculated using rigid body geometric transformation relationships.

8. The method for correcting the coaxiality of the rotor for a booster compressor according to claim 7, characterized in that, The steps for performing gasket combination optimization calculations and outputting gasket combination schemes include: Establish a calculation relationship with the objective of minimizing the difference between the actual gasket assembly thickness and the target total thickness; Based on the standard shim thickness specifications available on site, determine the combination of shims that minimizes the adjustment error of each base support point. Calculate the thickness cutoff error at each base support point, and adjust the residual torque balance of the torque trend caused by the thickness cutoff error. Combine the adjusted number of gaskets as the gasket combination scheme.

9. The method for correcting the coaxiality of a rotor for a booster compressor according to claim 6, characterized in that, The steps for outputting the lateral micro-displacement include: The lateral micro-displacement used to adjust the horizontal position of the base is calculated based on the coordinate difference in the horizontal radial direction between the newly corrected target point and the current intersection point to be corrected.

10. The method for correcting the coaxiality of a rotor for a booster compressor according to claim 6, characterized in that, The steps for re-measuring using the aforementioned three-dimensional laser measuring device to determine tolerance include: The coordinates of the current intersection point to be corrected and the current integrated spatial angle are obtained by re-measuring; Calculate the geometric distance residual based on the current intersection point coordinates to be corrected and the new corrected target point in the corrected target parameters, and calculate the angle residual based on the current integrated spatial angle and the corrected target angle in the corrected target parameters; Determine whether the geometric distance residual exceeds the preset displacement tolerance, and determine whether the angle residual exceeds the preset angle tolerance; If the geometric distance residual does not exceed the preset displacement tolerance and the angle residual does not exceed the preset angle tolerance, then the centering result is output as qualified. If the geometric distance residual exceeds the preset displacement tolerance, or the angle residual exceeds the preset angle tolerance, and the current number of adjustments does not exceed the maximum number of iterations threshold, then the current intersection coordinates to be corrected and the current comprehensive spatial angle are used as new inputs to regenerate the gasket combination scheme and the lateral micro-displacement. If the geometric distance residual exceeds the preset displacement tolerance, or the angle residual exceeds the preset angle tolerance, and the current number of adjustments exceeds the maximum number of iterations threshold, then the adjustment will be stopped and an error message will be output.

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