Effect Of Discharge Board On Velocity Control Of Corrosion Detector In Gas Pipeline And Its Application

With the development of state construction and the importance of environmental protection,the demand for natural gas has been increasing year by year.At present,the gas transmission of most main natural gas pipelines has reached their maximum designed capacity,leading the operating speed of detectors in such pipelines to be far beyond the optimal operating speed range of the equipment.This may affect the detectors' probes,odometry wheels and other electronic devices while collecting pipeline data and result in invalid test results;or even increase the operating risk of detectors in the pipelines—it may impair its own parts and also damage the internal structure of the pipeline and its accessories.A detector equipped with a speed controller can actively regulate its speed during operation.At present,most speed controllers are developed based on the principle of discharge(to slow down detectors by discharging parts of driving media).However,most corrosion detectors currently in use are not equipped with speed controllers.Based on the strict requirements of pipeline owners on detecting period,this paper has introduced a discharge board structure which can be replaced easily and is suitable for industrial fields.By changing relevant parameters of the discharge board,this structure can make the speed of detectors adapting to the requirements of the working conditions of pipelines,so as to accomplish field application.From the perspective of field application,this paper has simplified the structure of corrosion detectors equipped with discharge boards,starting with the relationship between the parameters of discharge boards and the the speed of corrosion detectors while operating in pipelines.By establishing relevant physical models of detectors operating in pipelines after discharging,this paper has analyzed and pointed out the functional relationship between the operation speed of detectors after discharging and the dimensions of discharging holes.Then,a finite element numerical simulation was carried out via the ANSYS software.The optimum parameters of discharge boards for detectors in operation for field application was figured out after considering the working conditions of pipelines,adjusting the parameters of discharging holes(dimension,amount,shape,etc.)and simulating the influence law of the structural changes of discharging holes on the discharging capacity of gases.Industrial application has proved that the operation speed of corrosion detectors equipped with discharge boards was effectively regulated and the quality of inspection data was greatly improved.With the transfer of national energy strategy and the emphasis on environmental protection,as a clean energy,natural gas is increasingly needed.Therefore,the media transporting speed of natural gas pipelines is becoming faster and faster.The method of using discharge boards as speed regulator presented in this paper has the following advantages: The structure of the discharge boards is simple,so it is easy to select the appropriate amount of discharging holes according to the relevant working conditions of pipelines.As for structural limitation,discharge boards are suitable for those pipeline-cleaners or detectors which are unable to be equipped with speed controllers.Also,compared with the complex electromechanical constitution of speed controlling system,the failure of the speed regulation caused by the malfunction under complex working conditions will not occur.Therefore,the application prospects of corrosion detectors equipped with discharge boards for the natural gas pipelines within a certain velocity range are wide and bright.