Development Of Surface Runout And Dynamic Balance System Of Paper Machine Dryer

With the improvement of mechanical efficiency in paper industry,the speed of paper machine is getting faster and faster.Drying cylinder is one of the core components of paper machine,and its performance is directly related to the quality of paper,reliability and life of paper machine.Therefore,this paper designs a comprehensive test system for measuring dynamic balance and surface runout of dryer cylinder in paper machine,aiming at solving the problem of imbalance of dryer cylinder,measuring surface runout,reducing equipment vibration and improving paper quality.The main research contents of this subject are as follows:1.Based on the high linearity eddy current sensor,the signal conditioning circuit is built and the upper computer software is programmed to measure surface runout.The piezoelectric acceleration sensor is used to measure the natural frequency by hammering oscillation.2.Based on the state variable filter,a tracking filter is constructed by combining low impedance analog switch and phase-locked frequency multiplication circuit,and a 32-bit switched capacitor narrowband tracking filter with constant bandwidth is designed so that the pass-band of the filter can reach within 1Hz,so as to effectively filter out the interference signal and extract the dynamic balance vibration signal.Innovative use of minimum condition fitting algorithm to solve the amplitude and phase of dynamic balance signal,with higher accuracy,and reduce the interference of random error to the signal.3.Build the peak value capture circuit of transient signal,capture and read the peak value of signal through single-chip computer and AD acquisition module,and realize automatic program-controlled amplification.A program-controlled amplifier with 1-64 times and 64 arbitrary switching amplifiers is designed.4.A perfect system self-test module is established to detect the hardware circuit and software algorithm respectively.STC15F2K60S2 single-chip microcomputer is used to collect the signal of the key measuring points in the circuit,and the signal is transmitted to the upper computer to draw the waveform and display the signal parameters,so as to realize the detection of the hardware circuit of the dynamic balance measurement system;the hardware circuit is built by the single-chip microcomputer and TLC5615 ten bit DA conversion chip,realizing the signal generation module with adjustable amplitude and frequency,so as to simulate the vibration signal The dynamic balance measurement software system is tested by the signal.5.Build data acquisition card by STM32F407VET6 and AD7606 to satisfy three different measurements and realize three different acquisition forms.At the same time,it meets the requirements of periodic fixed point acquisition for dynamic balance measurement,adaptive sampling frequency acquisition method,fixed sampling frequency for surface runout measurement,fixed cycle number sampling method and fixed sampling frequency fixed sampling point sampling method for natural frequency test;It uses Bluetooth serial port module to realize wired and wireless data transmission.The Bluetooth data transmission mechanism is established in four aspects to improve the stability and reliability of data transmission.