Abstract: A method for calculating eccentricity of rotor assembly axis based on radial runout measurement comprises matrix characterization of data and calculation of relative runout value at each point, establishment of a spring equivalent model and calculation of contact force, eccentric direction and magnitude; calculation of relative runout value; establishment of a spring equivalent model to analyze the relationship between force and displacement in each phase of a contact process, and then an uneven contact force at each point is obtained; and determination of eccentricity is to determine the magnitude of eccentricity. Based on the measured radial runout data in production practice, this method realizes the prediction of eccentricity of axis before assembly, improves the coaxiality of rotors after assembly, and has important practical guiding significance for axis prediction as well as assembly phase adjustment and optimization in the assembly process of aero-engine rotor pieces.

Abstract: The present invention belongs to the technical field of multiple bolt transverse load loosing testers, and relates to a closed loop control method for transverse load amplitude of multiple bolt loosing tester. The closed loop control method is used to conduct stepless amplitude modulation and accurate control for transverse loads of a multiple bolt loosing tester, thereby realizing stepless amplitude modulation and accurate control for the transverse loads. The closed loop control method is realized based on the multiple bolt loosing tester. The multiple bolt loosing tester consists of four parts: a transverse load amplitude control part, a transverse load transmission part, a torque load transmission part and an axial load transmission part. The present invention can provide stepless amplitude modulation continuous transverse loads for a flange bolt set and guarantee the accuracy of the transverse loads through a closed loop control system.

Abstract: The present invention discloses an interface ultrasonic reflectivity-pressure relation curve establishment method and a loading testbed. The loading testbed comprises a force displayer, a control terminal, an oscilloscope, an immersion ultrasonic transducer, a large cylinder, a small cylinder, an upper panel, a movable plate, a force sensor, a lower panel, an ultrasonic transceiver and a small cylinder connecting plate. Compared with the existing schemes, the interface ultrasonic reflectivity-pressure relation curve establishment method and the loading testbed provided by the present invention can construct a more accurate ultrasonic reflectivity-pressure relation curve, and are high in detection precision.

Abstract: The present invention discloses a piezoelectric patch-based real-time and high-precision bolt preload detection method and system. A piezoelectric patch is used as an ultrasonic excitation source and pasted on the head of a bolt, and the high-precision fitting relationship between the ultrasonic change of time-of-flight and the bolt preload is established according to the law of the ultrasonic change of time-of-flight of single echo with the stress so that the real-time detection of the bolt preload is realized by using the mathematical relationship. Compared with the previous method using ultrasonic probes, the present invention eliminates the error caused by the uncertainty of couplant thickness and further improves the measurement precision by using the change of time-of-flight of single echo. Meanwhile, the low-error rate measurement of the bolt preload is realized at a low cost and without affecting the structural performance.

Abstract: The present invention belongs to the technical field of joint surface pressure detection of connecting pieces, and provides an FBG sensor-based bolt fastening joint surface pressure detection method, comprising the steps of determining the size and the position of an FBG sensor; and determining the pressure of a joint surface measuring position on the basis of the single bolt connection joint surface pressure distribution theory, and completing calibration in real-time correspondence to the strain and pressure values to realize precise detection of the joint surface pressure. Determining the size and the position of the FBG sensor embedding slot according to the above method can ensure the reliability and accuracy of strain information; and an accurate strain-joint surface pressure curve can be obtained in combination with the determination of the joint surface pressure, which provides a practical and feasible method for the research on the bolt connection joint surface pressure.

Abstract: A method for calculating axis deviation of rotor assembly based on end face runout measurement comprises three parts: calculation of three contact points, a triangle judgment criterion and a homogeneous coordinate transformation algorithm of a deviation matrix. Based on the measured end face runout data in production practice, the method realizes the prediction of axis deviation before assembly, improves the concentricity of rotors after assembly, also greatly increases the one-time acceptance rate of assembly and has important practical guiding significance for axis prediction as well as assembly phase adjustment and optimization in the assembly process of aero-engine rotor pieces.

Abstract: The present invention provides a typical rotational part characterization method based on actually measured run-out data. Aiming at the characterization of rotational parts containing morphology data, the present invention proposes a matrix form characterization method in which microscopic run-out data and macroscopic axial size are comprehensively considered. In addition, the method can be applied to an assembly accuracy calculation process, and can characterize a single part containing morphology feature quantities by using only one matrix M. The calculation process of accuracy transfer is simplified, and a high-efficiency calculation model is provided for the prediction of assembly accuracy.

Abstract: The present invention belongs to the technical field of mechanical testing devices, and provides a transverse load stepless amplitude modulation device of multiple bolt loosing tester. The transverse load stepless amplitude modulation device of multiple bolt loosing tester consists of four parts: a transverse load stepless amplitude modulation part, a transverse load transmission part, a torque load transmission part and an axial load transmission part. The transverse load stepless amplitude modulation device of multiple bolt loosing tester of the present invention provides stepless amplitude modulation continuous transverse loads for a flange bolt set and guarantees the accuracy of the transverse loads through a feedback control system.

Abstract: Disclosed is a system for shape error in-situ measurement of large-scale torus, which comprises an attitude adjusting part, a rotating part and a measuring part.

Abstract: A method for calculating axis deviation of rotor assembly based on end face runout measurement comprises three parts: calculation of three contact points, a triangle judgment criterion and a homogeneous coordinate transformation algorithm of a deviation matrix. Based on the measured end face runout data in production practice, the method realizes the prediction of axis deviation before assembly, improves the concentricity of rotors after assembly, also greatly increases the one-time acceptance rate of assembly and has important practical guiding significance for axis prediction as well as assembly phase adjustment and optimization in the assembly process of aero-engine rotor pieces.

Abstract: A method for calculating eccentricity of rotor assembly axis based on radial runout measurement comprises matrix characterization of data and calculation of relative runout value at each point, establishment of a spring equivalent model and calculation of contact force, eccentric direction and magnitude; calculation of relative runout value; establishment of a spring equivalent model to analyze the relationship between force and displacement in each phase of a contact process, and then an uneven contact force at each point is obtained; and determination of eccentricity is to determine the magnitude of eccentricity. Based on the measured radial runout data in production practice, this method realizes the prediction of eccentricity of axis before assembly, improves the coaxiality of rotors after assembly, and has important practical guiding significance for axis prediction as well as assembly phase adjustment and optimization in the assembly process of aero-engine rotor pieces.

Abstract: The present invention belongs to the technical field of multiple bolt transverse load loosing testers, and relates to a closed loop control method for transverse load amplitude of multiple bolt loosing tester. The closed loop control method is used to conduct stepless amplitude modulation and accurate control for transverse loads of a multiple bolt loosing tester, thereby realizing stepless amplitude modulation and accurate control for the transverse loads. The closed loop control method is realized based on the multiple bolt loosing tester. The multiple bolt loosing tester consists of four parts: a transverse load amplitude control part, a transverse load transmission part, a torque load transmission part and an axial load transmission part. The present invention can provide stepless amplitude modulation continuous transverse loads for a flange bolt set and guarantee the accuracy of the transverse loads through a closed loop control system.

Abstract: The present invention belongs to the technical field of joint surface pressure detection of connecting pieces, and provides an FBG sensor-based bolt fastening joint surface pressure detection method, comprising the steps of determining the size and the position of an FBG sensor; and determining the pressure of a joint surface measuring position on the basis of the single bolt connection joint surface pressure distribution theory, and completing calibration in real-time correspondence to the strain and pressure values to realize precise detection of the joint surface pressure. Determining the size and the position of the FBG sensor embedding slot according to the above method can ensure the reliability and accuracy of strain information; and an accurate strain-joint surface pressure curve can be obtained in combination with the determination of the joint surface pressure, which provides a practical and feasible method for the research on the bolt connection joint surface pressure.

Abstract: The present invention provides a testing machine for accurately controlling looseness of a transverse load, and belongs to the technical field of mechanical testing devices. The testing machine for accurately controlling looseness of the transverse load uses a motor to control the generated transverse displacement, controls the generated transverse load by controlling the motor, and controls the motor through signal feedback from the sensor to keep the generated transverse load basically stable within a small range of a fixed value. Unlike the existing testing machine for looseness of the transverse load that can only provide one fixed transverse displacement load, the present invention can provide a desired stable transverse displacement load and can provide a desired stable transverse force load to adapt to simulation experiments for different bolt loading conditions.

Abstract: The present invention discloses a piezoelectric patch-based real-time and high-precision bolt preload detection method and system. A piezoelectric patch is used as an ultrasonic excitation source and pasted on the head of a bolt, and the high-precision fitting relationship between the ultrasonic change of time-of-flight and the bolt preload is established according to the law of the ultrasonic change of time-of-flight of single echo with the stress so that the real-time detection of the bolt preload is realized by using the mathematical relationship. Compared with the previous method using ultrasonic probes, the present invention eliminates the error caused by the uncertainty of couplant thickness and further improves the measurement precision by using the change of time-of-flight of single echo. Meanwhile, the low-error rate measurement of the bolt preload is realized at a low cost and without affecting the structural performance.

Abstract: The present invention belongs to the technical field of mechanical testing devices, and provides a transverse load stepless amplitude modulation device of multiple bolt loosing tester. The transverse load stepless amplitude modulation device of multiple bolt loosing tester consists of four parts: a transverse load stepless amplitude modulation part, a transverse load transmission part, a torque load transmission part and an axial load transmission part. The transverse load stepless amplitude modulation device of multiple bolt loosing tester of the present invention provides stepless amplitude modulation continuous transverse loads for a flange bolt set and guarantees the accuracy of the transverse loads through a feedback control system.

Abstract: A closed-loop control method based on a testing machine for accurately controlling the loosening of a bolt transverse load is disclosed. The testing machine for accurately controlling the loosening of the transverse load comprises a load generating motor, a load transfer mechanism, a load control motor and a load control mechanism. The control method of the present invention controls the load generating motor to drive the load transfer mechanism based on control commands, displacement signals collected by the displacement sensor and force signals collected by an S-shaped column type pressure sensor. The testing machine for the looseness of the bolt transverse load is essential in the aspect of exploring a looseness law of a bolt, and can be used to simulate load bearing conditions of the bolt. However, under the condition that some bolts bear constant force load transversely, the testing machine is not used or is inaccurate.

Abstract: The present invention belongs to the technical field of mechanical test devices, and provides a multi-bolt loosening test machine for flange with tension and bending compound loading, which is a test machine researching the anti-looseness properties of bolts by applying tension, bending and torsion compound loading to multi-bolt connection flanges. The multi-bolt loosening test machine for flange with tension and bending compound loading uses a transverse load generated by a three-phase asynchronous motor as a bending load applied to a flange, uses a tension force generated by a hydraulic puller as an axial tension load, is different from the current device that can apply two compound loads to a single bolt, and can apply two compound loads to the multi-bolt connection flanges. The present invention can isolate two compound loads from each other without interference, and display the applied loads in real time.

Abstract: The present invention provides a multi-bolt loosening test machine for flange with tension, bending and torsion compound loading. The multi-bolt loosening test machine for flange with tension, bending and torsion compound loading uses a transverse load generated by a three-phase asynchronous motor as a bending load applied to a flange, uses a tension force generated by a hydraulic puller as an axial tension load, and uses a torque generated by a servo motor as a torque load applied to the flange. The test machine is different from the current device that can apply two compound loads to a single bolt, and can apply three compound loads to the multi-bolt connection flanges. The present invention can isolate three compound loads from each other without interference, and display the applied loads in real time.

Abstract: The present invention belongs to the technical field of mechanical test devices, and provides a multi-bolt loosening test machine for flange with tension and bending compound loading, which is a test machine researching the anti-looseness properties of bolts by applying tension, bending and torsion compound loading to multi-bolt connection flanges. The multi-bolt loosening test machine for flange with tension and bending compound loading uses a transverse load generated by a three-phase asynchronous motor as a bending load applied to a flange, uses a tension force generated by a hydraulic puller as an axial tension load, is different from the current device that can apply two compound loads to a single bolt, and can apply two compound loads to the multi-bolt connection flanges. The present invention can isolate two compound loads from each other without interference, and display the applied loads in real time.