Design Of Scale Removal Robot For Long Distance Oil Pipeline And Experimental Study On Removal Efficiency Of Hard Scale

Pipeline transportation is the main mode of crude oil transportation,and the oil transportation trunk lines have spread all over the country,and the mileage is still increasing year by year.The dirt generated inside the oil pipeline will reduce the flow area of the pipeline,increase the oil resistance,accelerate the pipeline corrosion,and cause safety accidents.The removal of dirt in oil pipeline has always been a big problem in the industry.At present,pigging technology is often used to remove the dirt in oil pipeline,but this method can only remove the soft dirt,but can not effectively remove the hard dirt.However,most of the other effective descaling methods are only effective for short distance pipelines and cannot be used for long distance pipelines.In order to effectively remove all kinds of dirt in the long oil pipeline,this paper mainly designs a kind of long oil pipeline descaling robot,which is driven by hybrid fluid and electricity and descaling by mechanical means.Because the robot removes the hard scale by milling,the relationship between milling parameters and the removal efficiency of hard scale is also studied in this paper.The detailed research contents are as followsFirstly,the design and functional requirements of the robot are comprehensively analyzed,and the overall scheme of the pipeline descaling robot is proposed,and the dimensional constraints of the pipeline robot are analyzed.On this basis,the mechanism of each unit of the robot is analyzed and designed in detail,including the design of end face rotary valve type discharge mechanism,crank slider type reducing mechanism,cam speed regulating mechanism and the preliminary design of tool rest mechanism.The three-dimensional model of the whole robot is established.Then,the relationship between milling parameters and removal efficiency of hard scale is studied.According to the purpose of the test,the evaluation index of the test is determined.On this basis,the functional analysis of the test-bed is completed,and the test-bed is designed and built.The scheme of preparing hard scale in research laboratory is discussed and the hard scale for test is successfully prepared.The single factor test and orthogonal test of descaling efficiency changing with milling parameters are carried out.The analysis of the test results provides guidance for the selection and design of the working parameters of the tool holder mechanism.Then,according to the results of the experimental study,the working parameters of the turret mechanism are determined.By using the gradient descent method,the tooth number combination which can minimize the space occupied by the epicyclic gear train in the turret mechanism is obtained.Adams is used to simulate the dynamic characteristics of the turret mechanism,which verifies the correctness of the design of the turret mechanism and provides boundary conditions for the finite element analysis.ANSYS is used to analyze the key parts of the turret mechanism.The results show that the strength of the turret mechanism meets the requirements.Finally,Adams is used to simulate the pipe passing ability of the robot,and the rationality of the robot structure is verified.Fluent is used to simulate and analyze the fluid driving characteristics of the pipeline descaling robot,and the flow field distribution and fluid driving characteristic curve of the pipeline descaling robot are obtained,which provides a reference for the subsequent related research.