Pipelines　are　susceptible　to　corrosion,　perforation,　and　leakage　during　extended　service,　which　poses　a　significant　threat　to　their　safe　operation.　Consequently,　long-term　monitoring　is　essential　for　ensuring　the　continued　health　of　pipelines.　Ultrasonic　guided　wave,　particularly　the　non-dispersive　T(0,1)　mode,　is　widely　used　in　pipeline　detection　and　monitoring　due　to　its　large　detection　range　and　high　sensitivity　to　defects.　In　this　study,　a　high-performance　magnetostrictive　guided　wave　cloud　monitoring　system—featuring　remote　control,　wireless　transmission,　self-power　supply,　and　low　energy　consumption—was　developed　and　used　for　a　one-year　guided　wave　monitoring　experiment.　For　the　first　time,　up　to　1,951　sets　of　monitoring　data　were　recorded　from　a　complex　pipeline　with　multiple　types　of　defects　under　fluctuating　environmental　temperatures.　These　data　were　analyzed　to　evaluate　the　system＇s　detection　capabilities　and　stability,　while　also　assessing　the　impact　of　temperature　variations　on　guided　wave　signals,　with　a　particular　focus　on　the　relationship　between　multi-type　defect　signals　and　temperature　changes.　Additionally,　a　defect　expansion　identification　algorithm　was　developed,　enabling　the　identification　of　defect　expansion　in　real　pipelines　under　varying　temperature　conditions,　thus　confirming　the　system＇s　effectiveness.　The　study　provides　valuable　insights　for　the　ultrasonic　guided　wave-based　structural　health　monitoring　of　petrochemical　pipelines.　©　2025