The Cryogenic Freezing of Non-metallic Pipelines

摘要

Pipe freezing is increasingly used in arnrange of industries to solve otherwise intractablernpipe line maintenance and servicingrnproblems. This paper presents the interimrnresults from an experimental studyrnon deliberate freezing of polymeric pipelines.rnPrevious and contemporary worksrnare reviewed. The object of the current researchrnis to confirm the feasibility of icernplug formation within a polymeric pipe asrna method of isolation. Tests have beenrnconducted on a range of polymeric pipes ofrnvarious sizes. The results reported here allrnrelate to freezing of horizontal pipelines.rnIn each case the process of plug formationrnwas photographed, the frozen plug pressure-rntested and the pipe inspected for signsrnof damage resulting from the freeze procedure.rnThe time to freeze was recorded andrnvarious temperatures logged. The testsrnhave demonstrated that despite the poorrnthermal and mechanical properties of thernpolymers, freezing offers a viable alternativernmethod of isolation in polymeric pipelines.