What Does Preconditioning Work Mean?
Preconditioning work can be defined as the tasks associated with preparing sewer pipelines for rehabilitation work. It involves tasks such as dirt and silt removal, removal of accumulated solids or semisolids, grease, oil etc.
Trenchless inspection methods such as video inspection using closed circuit television cameras (CCTV) and other methods allows contractors to inspect pipelines without opening up the ground surface. To get a clear picture of the condition of a pipeline, it needs to be free from obstructions to help pinpoint problem areas and choose the most economical method of trenchless rehabilitation.
Trenchlesspedia Explains Preconditioning Work
Preconditioning is an essential part of trenchless rehabilitation. It involves removal of accumulated debris including solids, semisolids, slime, grease, gravel, etc. It also involves the removal of tree roots intruding into the pipe, manholes with corroded concrete & rusted rungs and intruding lateral connections.
Some preconditioning rules require that a minimum of 95% of the flow channel and sewer cross section has been cleared of all silt. Video inspection is used to determine the quality of preconditioning prior to rehabilitation. Methods such as cured-in-place pipe (CIPP), thermoformed pipe, fold and form liner etc. are used to rehabilitate pipes and require proper preconditioning work prior to installation of a liner.