The Corrosion Monitoring Of Buried Heating Pipe And Security Analysis Of The Pipe Network

Direct burial of the heating pipe technology has been widely used in urban central heating pipe network for its favorable economics, short construction period and less heat loss. However, long time using as well as the complexity of the underground environmentresults in the corrosion on the buried pipeline. Due to the buried pipe being laid underground, overhaul and maintenance seems more complex. Pipeline corrosion monitoring technology is able to achieve real-time monitoring of the corrosion of steel pipe, helps to take preventive and protective measures to prevent the occurrence of the accident, and protect the safe operation of the heating pipe network.First, based on the town buried heating pipe engineering point of order (CJJ/T81-98), introduce the principles and formulas for heating pipe stress. According to the different stress analysis and strength conditions, in accordance with the method of stress classification, analyze the elastic and stability of the anchoring section and sliding segment of the pipe, derivate the minimum wall thickness of the pipe under normal operating conditions. To analyze the safe operation of the pipeline network in view of the stability, check the stress of the vertical stability and local stability of the pipe network and deduce the minimum thickness requirements that meet the stability of the pipe network under normal operating conditions.Second, by summing up the previous study on corrosion on heating pipes, petrochemical pipelines and power plant cooling water of carbon steel and other mediums, analyze and summarize buried heating pipe wall corrosion law, establish the pipe wall corrosion hanging-tablets weight loss method test model. Analyze and tidy the inner wall of the pipeline corrosion data, obtain the corrosion rate of the pipe wall which changes over time.Then propose an effective method to monitor the pipe wall corrosion. Through establishing a heating pipe corrosion model by experimental methods, monitoring the corrosion of buried pipe outer wall by fiber optic sensors, achieve real-time, distributed monitoring of the entire pipe wall of the pipe network and obtain the corrosion rate of the pipe wall that changes over time.Finally, derive the pipe network rust evaluation formula. Through examples, analyze the pipe network health, forecast the remaining life of the pipeline according to the monitoring corrosion rate and guide the safe operation of the heating pipe network.