Water supply and sewerage networks having deposits on inside surfaces of metal pipe walls: systematization of hydraulic design

Abstract

Introduction. The purpose of the research is to establish the criterion for assessing the pipeline operation efficiency and verify the accuracy of hydraulic design of metal pipes that have internal deposits. Materials and methods. The authors provide calculated dependences to determine the values of the characteristics of the hydraulic potential of metal pipes having internal deposits. A specific case is employed to compare the characteristics of new pipes and pipes having different thicknesses of the layer of internal deposits. The percent discrepancy between pipe characteristics is provided. Results. The authors recommend evaluating the accuracy of the hydraulic design of water supply and sewerage networks having internal deposits in reliance on the value of the operation efficiency coefficient for water supply or sewerage networks. The authors offer a formula derived to determine the value of the efficiency coefficient for the operation of water supply and sewerage networks having internal deposits on inside walls of a pipe. The authors suggest systematizing the hydraulic design of metal water supply and sewerage networks that are made of metal and have deposits on the inside of pipe walls by taking into account the thickness of the layer of internal deposits, characterized by the value of the network operation efficiency coefficient. Conclusions. Systematization of hydraulic design of water supply and sewerage networks that are made of metal and have deposits on the inside of pipe walls allows for the acceptable accuracy of its hydraulic design that takes account of the actual value of the coefficient of efficiency of pipeline operation Kef, taking into account the value of actual thickness of deposit layer σact. In other words, systematization of hydraulic design of water supply and sewerage networks, having deposits on the inside surface of metal pipes, is based on the value of their efficiency coefficient Kef, that takes into account the actual hydraulic potential of pipes (pipelines) depending on the layer of internal deposits σact.

Efficiency coefficient of water supply and removal as an assessment factor of further operation

“…Приведенные выше причины изменения значений характеристик гидравлического потенциала труб способствуют также образованию слоя отложений на внутренней поверхности водопроводных труб или слоя отложений (осадка) в лотковой части труб водоотведения [4,5]. Каким критерием следует оценивать изменение значений гидравлических характеристик труб?…”

Condition classification of sewerage systems according to the deposit layer thickness in the bench part of pipes

“…Вопрос, связанный с проведением гидродинамической очистки и выводом сети из эксплуатации для последующей реконструкции и замены труб, является одним из основных для организаций, эксплуатирующих сети водоснабжения или водоотведения с внутренними отложениями [1][2][3].…”

On the need to account changes in hydraulic performance of worn-out metal water pipes

“…The form of formula (6) specified by the authors, taking into account the thickness of the layer of internal deposits δ a , looks as follows [6]:…”