| Title |
Evaluation of Water Quality Characteristics Effects on the Internal Corrosion of Galvanized Steel Service Pipe in the Building |
| Authors |
이현동(Hyun Dong Lee),배철호(Chul Ho Bae),박정훈(Jeong Hoon Park),정원식(Won Sik Chung),곽필재(Phil Jae Kwak) |
| Abstract |
The effects of water quality characteristics on internal corrosion of galvanized steel service pipe(GSP) in the building were evaluated qualitatively and quantitatively, and the time of its replacement were predicted in the study. The results showed that water quality characteristics of Nakdong River water resources in both anti-corrosion factors(pH, Alkalinity, Hardness etc..,) and corrosion factors(Conductivity, Chloride ion, Sulfate ion etc..,) were higher than any other water quality of major water resources. And water corrosivity of water resources were seem to depend on the method of evaluation such as LI, LR, and BI. And Nakdong River water resources also was thought to be high in the evaluation of corrosion indices such as LR and BI especially. Therefore the results of the evaluation also showed that water corrosivity of Nakdong River water resources were higher than any other water resources entirely. Corrosion rate measurement by Corrator showed that uniform and pitting corrosion rates were 0.075 mmpy and 1.333 mmpy in Nakdong River water resources, 0.070 mmpy and 0.834 mmpy in lake water resources, and 0.065 mmpy and 0.445 mmpy in Han River water resources. And pitting corrosion were thought to be predominant corrosion type in GSP. The time of GSP replacement were thought to be about from 14.1 years to 16.2 years if considering only a straight part of GSP by uniform corrosion rate. Otherwise if a screw part, the time of Its replacement would be about from 6.7 years to 7.7 years. But if pitting corrosion rate, the time would be shorter. Residual thickness measurement of GSP by ultrasonic waves showed that average and maximum corrosion rates were 0.054 mmpy and 0.084 mmpy in Nakdong River water resources, 0.041 mmpy and 0.055 mmpy in lake water resources, and 0.022 mmpy and 0.032 mmpy in Han River water resources, and all average and maximum corrosion rake were lower than corrosion rate by Corrator. |