| Polyurethane sealing disk is an important component of pipeline pigging equipment.Friction vibration will occur during the contact between flexible sealing disk and rigid pipe wall.This phenomenon will aggravate the abrasion of polyurethane sealing ring surface material and reduce the stability of pipe cleaner.At present,there are few studies on vibration characteristics and friction and wear properties of polyurethane sealing rings.Based on the real contact state of the polyurethane sealing disk in the pipeline,this paper mainly conducts the following research:(1)The structure and pigging principle of polyurethane peel bowl pig were introduced briefly.The research results of foreign and domestic scholars on the occurrence mechanism,influencing factors and signal acquisition and processing of friction vibration were investigated.The forms of friction and wear of polyurethane elastomers are summarized.(2)Using the transient dynamics module of Ansys Workbench 16.0,the finite element model of polyurethane sample-steel disk friction pair was established according to the real contact state of polyurethane sealing ring in the pipe,and the friction and vibration behavior of polyurethane ball sample under different loads was simulated.The influence of load change on the friction vibration characteristics of the ball sample is obtained by studying the time-frequency domain diagram of acceleration signal.By analyzing the displacement signal and the stress strain,the relationship between the load and the stress strain and the amount of compression is obtained.(3)A set of vibration signal acquisition and processing system is established on the pin-tray friction and wear tester,which is convenient for the experimental study of the friction and vibration response and wear performance of polyurethane ball samples under different working conditions.(4)In the condition of dry friction,the effects of positive load and sliding speed on the friction vibration and wear performance of polyurethane ball samples were studied experimentally.The relationship between the two factors and the friction coefficient and wear amount of the ball sample was obtained.Through the analysis of vibration signal,the relationship between the load and rotation speed and the friction vibration characteristics of the ball sample is obtained.The wear marks on the surface of the ball sample were taken as samples.The main wear patterns and their mechanism in the process of friction and wear were analyzed.(5)The friction,vibration and wear properties of ball samples were studied by using black powder with different moisture content as lubricating medium.The changes of friction coefficient and wear amount of pilling samples were obtained.The relationship between the moisture content of black powder and the friction vibration characteristics of ball sample was obtained by analyzing the vibration signal.The influence of black powder particles on the wear degree of the surface material was obtained by comparing with the surface wear marks of ball samples under dry friction condition.The similarities and differences of surface wear marks between dry friction and hydrous black powder are summarized. |
PDF Full Text Request