循環式給湯配管システムにおける溶存気体の挙動と銅管の潰食防止に関する研究

摘要

It has been envisaged that the action of the micro bubbles in the hot water could cause the erosion corrosion in copper pipes in the circulation type of hot water supply system. Keeping this in view, we investigated several buildings about the detail of the circulation systems in each building, the history of occurrence of erosion corrosion in copper pipes, the dissolved oxygen concentration and cloudiness in hot water in the piping system. In addition, we made a loop circulation working using experimental equipment in order to clarify and simulate the process and condition of micro bubbles generation in the closed type hot water piping system.rnFrom the result of the building investigation, it was shown that the erosion corrosion in copper pipes occurred only in the closed type hot water supply piping system, and also was suggested that the head of circulation pump could be strongly involved in the occurrence of erosion corrosion in copper pipes. According to the outcome of the loop circulation working, it was suggested that the existence of pressure difference in the pipe under flowing hot water could generate the micro bubbles on the downstream side of valve and around pipe connections such as elbows.%銅管を使用した循環式給湯配管システムにおける潰食rn発生や水質などの実態調査と，密閉型循環式給湯配管シrnステムを模擬したループ実験装置により微細気泡の発生rn条件に関する実験を行った。調査結果および実験結果かrnら得られた主な知見を以下に示す。