Research And Realization Of Damage Monitoring System For Expansion Joint Of Self-power Heat Pipe Network

With the popularization of central heating,as the tool for conveying heat medium,heat-supply pipe network has been widely used.As for the problem that it's easy to have damage for expansion joint of heat-supply pipe network that lead to the leakage,this paper has researched and designed a self-powered,maintenance-free,easy-installment monitoring system for the damage and leakage of heat-supply pipe network's expansion joint.The monitoring system for the damage of heat-supply pipe network's expansion joint consists of monitoring station,communication network and monitoring center.The monitoring station is responsible for collecting various parameters of expansion's joint outer wall around,which is transmitted to monitoring center by wireless network,then analyzed in monitoring center by data fusion technology,and finally could enable to monitor the running condition of expansion joint online.The monitoring station installed near heat-supply pipe network's expansion joint,with the microprocessor STC89C54RD+ as its core,collects the data of temperature of expansion joint around and soil conductivity by 4 temperature sensors and 1 conductivity sensor,and processes the auto adapted weighted data which is transmitted to data monitoring center by GPRS wireless network.It also has designed a thermoelectric power generator based on pyroelectric effect for monitoring station,which could supply continuously and stably power to monitoring station in case under the condition of no power supply.Monitoring center could display and store the data by WinCC configuration software,make date fusion for back-end store data by BP network algorithm,and use the data reflecting the parameters of expansion joint's running condition as sample to do training classification,by whose result could judge if there's any leakage for expansion joint,formulate a maintenance plan according to leakage severity,and remind the technician to deal with it timely.It's proved by testing that the output voltage of thermoelectric power generator could satisfy the power supply requirement of monitoring system though the multiply and series design of several thermoelectric power generating chips and rational design of radiating unit.It's proved simulation experiment that this system could judge accurately not only if there's any damage leakage but also the leakage severity.It could give an alarm when the expansion joint has any damage leakage by this system,remind technician to repair the problem timely,and then enable to reduce the loss caused by damage leakage of expansion joint,which has great significance for ensuring the normal residential heating.The self-powered monitoring system for the damage leakage of heat-supply pipe network's expansion joint has been successfully used in a thermal power plant,whose application result is good with meeting the design requirements.