Coaxiality optimization phase acquisition and assembly method for multi-stage high-speed rotating components based on gap fit and interference fit

Abstract

The application discloses a multi-stage high-speed rotating part coaxiality optimization phase acquisition and assembling method based on gap fit and interference fit, belongs to the field of mechanical assembling, and solves the problem of coaxiality excess of the high-speed rotating part based on gap fit and interference fit.The main points for solving the technical problem of the application are as follows: taking a central shaft as a reference, assembling the multi-stage gap high-speed rotating part, obtaining the cumulative eccentric error of the multi-stage gap fit high-speed rotating part after assembling and the position vector of the circle center of the n-stage high-speed rotating part assembling surface, fitting the interference fit high-speed rotating part with the multi-stage gap fit high-speed rotating part, obtaining the cumulative eccentric error of the n-stage high-speed rotating part after assembling and the axial projection of the n-stage high-speed rotating part shaft center position, that is, the optimization phase, determining the assembling position of the first-stage rotating part according to the phase, adjusting the rotating parts stage by stage, and assembling.The application is mainly used for guiding the assembling of the multi-stage high-speed rotating part based on gap fit and interference fit.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of mechanical assembly, and particularly relates to a multi-stage high-speed rotating component coaxiality assembly model of mixed assembly of clearance fit and interference fit. BACKGROUND

[0002] The measurement and assembly precision of high-speed rotating components such as engines directly determine the reliability, stability, comprehensive performance and service life of the whole machine. The failure of high-speed rotating components such as engines is mainly caused by vibration and rubbing, and the vibration and rubbing are mainly caused by the factors such as different shafts of the components after assembly and out-of-tolerance of unbalance.

[0003] Taking a current turbofan aero-engine as an example, the core engine is the most complex core unit in engine assembly, and the assembly precision of the core engine has a crucial influence on the performance of the engine.

[0004] The assembly of the rotating components of some existing engines is composed of clearance fit and interference fit, and such mixed assembly of the rotating components often leads to the coaxiality out-of-tolerance of the engine during assembly. In the high-speed state, the coaxiality out-of-tolerance will be rapidly magnified on the reliability, stability, comprehensive performance and service life of the whole machine. Therefore, in the field of engine equipment technology, especially for the mixed assembly of the rotating components of clearance fit and interference fit, how to reduce the coaxiality out-of-tolerance is an urgent technical problem to be solved. SUMMARY

[0005] The present application provides a multi-stage high-speed rotating component coaxiality optimization phase acquisition and assembly method based on clearance fit and interference fit, which solves the coaxiality out-of-tolerance problem of the multi-stage high-speed rotating components such as engines during assembly.

[0006] The multi-stage high-speed rotating component coaxiality optimization phase acquisition method based on clearance fit and interference fit comprises the following steps:

[0007] Taking the central shaft of the high-speed rotating component as a reference, the multi-stage clearance fit high-speed rotating component is assembled;

[0008] The cumulative eccentric error formula of the multi-stage clearance fit high-speed rotating component assembly is used to obtain the cumulative eccentric error of the multi-stage clearance fit high-speed rotating component assembly;

[0009] The data of the single-stage rotor is measured by a coaxiality measuring instrument, and the cumulative eccentric error formula of the multi-stage clearance fit high-speed rotating component assembly is used to obtain the position vector of the circle center of the n-th stage high-speed rotating component assembly surface after the multi-stage clearance fit high-speed rotating component assembly;

[0010] According to the position vector of the circle center of the n-th stage high-speed rotating component assembly surface, the interference fit high-speed rotating component is matched with the multi-stage clearance fit high-speed rotating component;

[0011] obtaining the cumulative eccentric error of the n-level high-speed rotating part after the clearance fit and interference fit mixed assembly;

[0012] obtaining the axial projection of the axial position of the n-level high-speed rotating part after the clearance fit and interference fit mixed assembly according to the cumulative eccentric error of the n-level high-speed rotating part after the clearance fit and interference fit mixed assembly;

[0013] The axial projection of the axial position of the n-level high-speed rotating part after the clearance fit and interference fit mixed assembly is the coaxiality optimization phase of the multi-level high-speed rotating part with clearance fit and interference fit.

[0014] Preferably, the multi-level clearance fit high-speed rotating part assembly has errors, and the errors are composed of positioning errors and orientation errors.

[0015] Preferably, the positioning error is determined by a translation matrix, and the orientation error is determined by a rotation matrix.

[0016] Preferably, the cumulative eccentric error expression of the multi-level clearance fit high-speed rotating part assembly is:

[0017]

[0018] wherein Trans ri is the transformation matrix between the two-level high-speed rotating part joint surfaces, Trans zi is the eccentricity of the ideal center of the high-speed rotating part i, Trans clearancei is the translation transformation matrix of the eccentricity of the high-speed rotating part i reference surface gap, Trans dzi is the eccentricity translation transformation matrix caused by the machining error of the high-speed rotating part i reference surface, Trans orientationi is the rotation transformation matrix of the high-speed rotating part i reference surface to the assembly surface rotation center, Ro xi is the rotation matrix of the i-level high-speed rotating part reference surface around the X-axis, Ro yi is the rotation matrix of the i-level high-speed rotating part reference surface around the Y-axis, Ro ri is the rotation matrix of the i-level high-speed rotating part around the Z-axis, Ro r(j-1) is the rotation matrix of the j-1-level high-speed rotating part around the Z-axis; Ro x(j-1) is the rotation matrix of the j-1-level high-speed rotating part reference surface around the X-axis; Ro y(j-1) is the rotation matrix of the j-1-level high-speed rotating part reference surface around the Y-axis P i is the ideal position vector of the assembly surface center of the i-level high-speed rotating part, dP i is the machining error vector of the assembly surface center position of the i-level high-speed rotating part, dP' iis the eccentric position vector of the i-th level of the high-speed rotating component with clearance.

[0019] Preferably, the expression of the center position vector of the assembly surface of the n-th level of the high-speed rotating component with clearance after the assembly of the high-speed rotating component with clearance is:

[0020]

[0021] Preferably, the assembly of the high-speed rotating component with interference and the high-speed rotating component with clearance is the assembly of the high-speed rotating component with interference as a single-level high-speed rotating component and the high-speed rotating component with clearance.

[0022] Preferably, the expression of the cumulative eccentric error of the n-th level of the high-speed rotating component after the mixed assembly of the clearance assembly and the interference assembly is:

[0023]

[0024] Trans deformationi is the translation transformation matrix of the deformation eccentricity caused by the interference assembly of the high-speed rotating component, Ro rj is the rotation matrix of the j-th level of the high-speed rotating component around the Z axis; Ro xj is the rotation matrix of the reference surface of the j-th level of the high-speed rotating component around the X axis; Ro yj is the rotation matrix of the reference surface of the j-th level of the high-speed rotating component around the Y axis; dP j is the interference assembly error value of the single-level rotor.

[0025] Preferably, the expression of the axial projection of the axial position of the n-th level of the high-speed rotating component after the mixed assembly of the clearance assembly and the interference assembly is:

[0026]

[0027] The method comprises:

[0028] For the multi-level high-speed rotating component to be assembled, first, the multi-level high-speed rotating component coaxial optimization phase acquisition method based on clearance assembly and interference assembly described in any one of the above contents is used to obtain the coaxial optimization phase of each level of the high-speed rotating component.

[0029] According to the obtained coaxial optimization phase of each level of the high-speed rotating component, the assembly phase of each level of the rotating component is adjusted step by step based on the first level of the rotating component, and the coaxial optimization assembly method of the multi-level high-speed rotating component to be assembled is completed.

[0030] The application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes any one of the methods for obtaining the coaxiality optimization phase of the multi-stage high-speed rotating component based on the gap fit and the interference fit.

[0031] The application has the following advantages:

[0032] Some existing engine high-speed rotating components are mixed assembled by gap fit and interference fit, but the misalignment and imbalance of the assembled components exceed the tolerance, which causes the vibration and friction of the high-speed rotating components and thus the failure.

[0033] Different high-speed rotating components have different coaxiality requirements, and the actual rotor is not a real rigid body, especially for small rotors and thin-walled rotors, the deformation caused by the assembly gap and interference will cause the accumulation of the assembly error of the multi-stage rotor, and thus the coaxiality and the imbalance of the rotor become larger, and the prediction accuracy of the coaxiality and other parameters will be obviously improved.

[0034] Generally, the maximum coaxiality error caused by random assembly is 5-6 times of the coaxiality error of the optimized assembly method of the application, and the random assembly will cause the coaxiality to exceed the standard, and in severe cases, the single assembly qualification rate is less than 50%.

[0035] The assembly qualification rate can be more than 85% by using the optimized assembly method of the application. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 The thick-walled cylinder theory based on the method of the application is shown in the schematic diagram.

[0037] Figure 2 The assembly schematic diagram of the multi-stage mixed assembly high-speed rotating component is shown in the schematic diagram.

[0038] As can be seen from the diagram, the multi-stage high-speed rotating component composed of the gap fit rotor and the interference fit rotor is shown from bottom to top, the third stage rotor is interference fit, the first two stage rotors are gap fit, the interference fit rotor is fit with the gap fit rotor as the bottom end face reference, the gap fit rotor is stacked by two gap fit rotors, and the position and posture of each stage rotor have different inclination directions due to the machining error and installation error of the rotor, and the whole shaft body rotates counterclockwise around the center as the axis. DETAILED DESCRIPTION

[0039] To make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in a clear and complete manner with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application.

[0040] As shown in Figure 2 the gap fit and the interference fit multi-stage mixed assembly high-speed rotating part assembly, first, the center shaft is taken as the reference, the multi-stage gap high-speed rotating part is installed, the cumulative eccentric error of the multi-stage gap fit high-speed rotating part assembly is obtained, the perpendicularity and the coaxiality of the single-stage rotor are measured by the coaxiality measuring instrument, the data are substituted into the cumulative eccentric error formula of the multi-stage gap fit high-speed rotating part assembly to predict the position vector of the circle center of the assembly surface of the nth high-speed rotating part after the multi-stage gap fit high-speed rotating part assembly, when the multi-stage gap high-speed rotating part is installed, the interference fit high-speed rotating part is matched with the multi-stage gap fit high-speed rotating part, the cumulative eccentric error of the nth high-speed rotating part after the gap assembly and the interference assembly is obtained, the axial projection of the axis position of the nth high-speed rotating part after the gap assembly and the interference assembly is obtained according to the cumulative eccentric error of the nth high-speed rotating part after the gap assembly and the interference assembly, the phase is adjusted according to the axial projection of the axis position of the nth high-speed rotating part, and the coaxiality expression of the multi-stage high-speed rotating part assembly is

[0041]

[0042] For the target, the phase optimization is performed in the software matched with the coaxiality measuring instrument, after the phases of the rotors are determined, the rotors are installed in sequence according to the phases, the overall coaxiality of the high-speed rotating part is optimized, so that the assembly precision of the engine is ensured. The overall coaxiality of the high-speed rotating part is twice the maximum modulus of the axial projection of the axis position of the nth high-speed rotating part after the assembly, that is,

[0043]

[0044] The specific multi-stage high-speed rotating part coaxiality optimization assembly method is as follows:

[0045] I. First, the multi-stage gap high-speed rotating part is assembled, the assembly error of the gap high-speed rotating part is composed of positioning error and directional error, the positioning error is determined by the translation matrix, and the directional error is determined by the rotation matrix.

[0046] Therefore, the general expression of the cumulative eccentric error of the multi-stage gap fit high-speed rotating part assembly is:

[0047]

[0048] Trans riTrans is the transformation matrix between the two high-speed rotating components of the two-stage high-speed rotating component zi Trans is the eccentricity of the ideal center of the high-speed rotating component i clearancei Trans is the translation transformation matrix of the eccentricity of the reference surface gap of the high-speed rotating component i dzi Trans is the translation transformation matrix of the eccentricity caused by the machining error of the reference surface of the high-speed rotating component i orientationi Ro is the rotation transformation matrix from the reference surface of the high-speed rotating component i to the rotation center of the assembly surface ri Ro is the rotation matrix of the i-th stage high-speed rotating component around the Z-axis xi Ro is the rotation matrix of the i-th stage high-speed rotating component reference surface around the X-axis yi Ro is the rotation matrix of the i-th stage high-speed rotating component reference surface around the Y-axis r(j-1) Ro is the rotation matrix of the j-1-th stage high-speed rotating component around the Z-axis x(j-1) Ro is the rotation matrix of the j-1-th stage high-speed rotating component reference surface around the X-axis y(j-1) P is the rotation matrix of the j-1-th stage high-speed rotating component reference surface around the Y-axis i dP is the ideal position vector of the assembly surface center of the i-th stage high-speed rotating component i dP' is the machining error vector of the assembly surface center position of the i-th stage high-speed rotating component i is the gap eccentricity position vector of the i-th stage high-speed rotating component.

[0049] II. By measuring the perpendicularity and coaxiality of the single-stage rotor with the coaxiality measuring instrument, the data is substituted into the multi-stage gap fitting high-speed rotating component assembly cumulative eccentricity error formula to predict the position vector of the assembly surface center of the n-th stage high-speed rotating component after assembly of the multi-stage gap fitting high-speed rotating component,

[0050] The position vector of the assembly surface center of the n-th stage high-speed rotating component after assembly is represented as:

[0051]

[0052] III. The interference fitting high-speed rotating component is fitted as a single-stage high-speed rotating component and a multi-stage gap high-speed rotating component. When the ratio of the outer diameter and the inner diameter of the high-speed rotating component exceeds 1.2, it can be simply equivalent to a thick-walled cylinder under internal pressure. Under ideal conditions, the shape profile and pressure load of the thick-walled cylinder are symmetrical about its axis, so the stress and strain at each point in the thick-walled cylinder are also symmetrical about the axis.

[0053] The thick-walled cylinder theory is suitable for the case without axial stress. As shown in Figure 1 According to the thick-walled cylinder theory, the stress and radial displacement expressions of the thick-walled cylinder are obtained by considering the geometric relationship, static relationship and physical relationship:

[0054]

[0055]

[0056] where σ r is the thick-walled cylinder radial stress, σ θ is the thick-walled cylinder circumferential stress, d is the thick-walled outer wall radius, d1 is the thick-walled inner wall radius, p1 is the thick-walled internal pressure, p2 is the thick-walled external pressure, r is the thick-walled cylinder radius variable, u is the thick-walled cylinder radial displacement, E is the thick-walled cylinder elastic modulus, and μ is the thick-walled cylinder Poisson's ratio.

[0057] The thick-walled cylinder theory is used to obtain the rotor interference fit error, that is, u = dP", and the rotor interference fit error of the jth stage rotor can be expressed as u j

[0058] Four, based on the assembly error analysis of the multi-stage gap high-speed rotating part and the single-stage interference high-speed rotating part, the cumulative eccentric error expression of the nth stage high-speed rotating part after the mixed assembly of the gap assembly and the interference assembly is:

[0059]

[0060] where Trans deformationi is the translation transformation matrix of the deformation eccentricity caused by the interference fit of the high-speed rotating part, dP" i is the eccentric position vector caused by the interference fit of the ith stage high-speed rotating part, Ro rj is the rotation matrix of the jth stage high-speed rotating part around the Z axis, Ro xj is the rotation matrix of the jth stage high-speed rotating part reference surface around the X axis, Ro yj is the rotation matrix of the jth stage high-speed rotating part reference surface around the Y axis, dP" j is the interference fit error value of the single-stage rotor.

[0061] Five, the axial projection of the axis position of the nth stage high-speed rotating part after the mixed assembly of the gap assembly and the interference assembly can be expressed as:

[0062]

[0063] According to the adjustment of the phase of the axial projection of the axis position of the nth stage high-speed rotating part, the coaxiality of the multi-stage high-speed rotating part with the gap fit and the interference fit is optimized, and the coaxiality optimization assembly method of the multi-stage high-speed rotating part with the gap fit and the interference fit is realized.

[0064] The method for adjusting the phase is that the coaxiality expression of the multi-stage high-speed rotating part assembly is

[0065]

[0066] For the target, the phase optimization is carried out in the coaxial degree measuring instrument matching software, and after the phases of the rotors are determined, the rotors are installed in sequence according to the phases.

[0067] Based on the position vector of the axial projection of the shaft center position of each high-speed rotating component, twice the maximum modulus of the position vector is the optimal coaxial degree of the multi-stage mixed fitting high-speed rotating component, and the coaxial degree expression is:

[0068]

Claims

1. A method for optimizing the phase acquisition of coaxiality of multi-stage high-speed rotating components based on clearance fit and interference fit, characterized in that, The method includes: Using the central axis of the high-speed rotating component as a reference, assemble a high-speed rotating component with multi-stage clearance fit. The cumulative eccentricity error of high-speed rotating components with multi-level clearance fit is obtained from the formula for the cumulative eccentricity error of the assembly of high-speed rotating components with multi-level clearance fit. By measuring the data of a single-stage rotor with a coaxiality measuring instrument, and substituting it into the expression for the center position vector of the assembly surface of the nth-stage high-speed rotating component after the assembly of the multi-stage clearance fit high-speed rotating component, the center position vector of the assembly surface of the nth-stage high-speed rotating component after the assembly of the multi-stage clearance fit high-speed rotating component is obtained. Based on the center position vector of the assembly surface of the nth-level high-speed rotating component, the interference fit high-speed rotating component is fitted with the multi-level clearance fit high-speed rotating component; The cumulative eccentricity error of the nth-stage high-speed rotating component after a mixed assembly of clearance and interference fit is obtained. Based on the cumulative eccentricity error of the nth stage high-speed rotating component after the mixed assembly of clearance fitting and interference fitting, the nth stage high-speed rotating component after the mixed assembly of clearance fitting and interference fitting is obtained. n Axial projection of the axis position of the high-speed rotating component; After the mixed assembly of clearance fitting and interference fitting, the first n The axial projection of the shaft center position of the multi-stage high-speed rotating component is the optimized phase of coaxiality of the multi-stage high-speed rotating component with clearance fit and interference fit. The expression for the cumulative eccentricity error of the multi-stage clearance fit high-speed rotating component assembly is as follows: in Trans ri This is the transformation matrix between the mating surfaces of the two-stage high-speed rotating components. Trans zi For high-speed rotating components i The eccentricity of the ideal center of the circle Trans clearancei For high-speed rotating components i Translation transformation matrix for eccentricity of datum plane gap. Trans dzi For high-speed rotating components i Eccentric translation transformation matrix caused by machining error of the reference surface Trans orientationi For high-speed rotating components i Rotation transformation matrix from the datum plane to the center of rotation of the assembly surface. Ro xi For the first i High-speed rotating component reference surface around X The rotation matrix of the axis. Ro yi For the first i High-speed rotating component reference surface around Y The rotation matrix of the axis. Ro ri For the first i High-speed rotating components Z The rotation matrix of the axis. Let be the rotation matrix of the (j-1)th stage high-speed rotating component about the Z-axis; Let be the rotation matrix of the reference plane of the (j-1)th stage high-speed rotating component about the X-axis; Let J be the rotation matrix of the reference plane of the (j-1)th stage high-speed rotating component about the Y-axis. P i For the first i The ideal position vector of the center of the assembly surface of a high-speed rotating component. dP i For the first i The machining error vector at the center position of the assembly surface of the high-speed rotating component. dP′ i For the first i Vector of eccentric position of high-speed rotating component clearance; The expression for the center position vector of the assembly surface of the nth-stage high-speed rotating component after the multi-stage clearance fit is as follows: ； The cumulative eccentricity error expression for the nth-stage high-speed rotating component after the mixed assembly of clearance assembly and interference assembly is: in Trans deformationi The translation transformation matrix is ​​for the deformation and eccentricity caused by the interference fit of the high-speed rotating component. Let be the rotation matrix of the j-th stage high-speed rotating component about the Z-axis; Let be the rotation matrix of the reference plane of the j-th high-speed rotating component about the X-axis; Let be the rotation matrix of the reference plane of the j-th high-speed rotating component about the Y-axis; This represents the interference fit error value for a single-stage rotor. After the mixed assembly of clearance fitting and interference fitting, the first n The expression for the axial projection of the shaft center position of the high-speed rotating component is: 。 2. The method for optimizing the phase acquisition of coaxiality of multi-stage high-speed rotating components based on clearance fit and interference fit according to claim 1, characterized in that, The assembly of the multi-stage clearance fit high-speed rotating component has errors, which consist of positioning errors and orientation errors.

3. The method for optimizing the phase acquisition of coaxiality of multi-stage high-speed rotating components based on clearance fit and interference fit according to claim 2, characterized in that... The positioning error is determined by a translation matrix, and the orientation error is determined by a rotation matrix.

4. The method for optimizing the phase acquisition of coaxiality of multi-stage high-speed rotating components based on clearance fit and interference fit according to claim 1, characterized in that, The process of fitting the interference fit high-speed rotating component with the multi-stage clearance fit high-speed rotating component means that the interference fit high-speed rotating component is used as a single-stage high-speed rotating component to fit with the multi-stage clearance fit high-speed rotating component.

5. A method for optimizing the coaxiality of multi-stage high-speed rotating components based on clearance fit and interference fit, characterized in that, The method includes: For the multi-stage high-speed rotary components to be assembled, firstly, the coaxiality optimization phase acquisition method for multi-stage high-speed rotary components based on clearance fit and interference fit as described in any one of claims 1-4 is used to obtain the coaxiality optimization phase of each stage of the high-speed rotary component; Based on the coaxiality optimization phase of each stage of high-speed rotating component, and taking the first stage rotating component as a foundation, the assembly phase of each stage of rotating component is adjusted step by step to complete the coaxiality optimization assembly method of the multi-stage high-speed rotating component to be assembled.

6. A computer device, characterized in that: It includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes the method for optimizing the phase acquisition of coaxiality of multi-stage high-speed rotating components based on clearance fit and interference fit as described in any one of claims 1-4.

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