The legislator found a quality problem about the anchor bolt, HDA-TF/PF, and Taipower had announced the information to clear up the misunderstanding. Actually, to plate with zinc is adopted to prevent corroding, and the steel bolt shouldn't be affected by the zinc. Taipower indicated the thickness of the plating with zinc is 53μm, and this thickness can satisfy the design life-span of the NPP IV, 40 years. Is it correct?
Let's see the info of the Galvanizing Association of Taiwan, http://www.galtw.org.tw/info.htm, and the relationship of the thickness and life-span can be calculated by the Table 2 and Table 5. In the Table 5, the thickness 53μm is between the grade 50 and 55, and the equilibrium amount of the zinc is 376g/m^2. In the Table 2, the amount of the zinc is in the closed interval 305~488g/m^2, and the equilibrium life-span is in the closed interval 35~50 years for the farm.
The life-span of the thickness 53μm is 40.8 years（coated duplex-system）, and it satisfies the design life-span of the NPP IV. In the general design result, the Factor of Safety should be considered by the designer, especially the extended life-span more than 0.8 year. Actually, the location is near the sea, not the farm. According to the similar calculation, the actual design life-span is 33.1 years for the sea（coated duplex-system）, and it reduces 7.7 years. If the adopted design life-space is extended to 50 years, the similar calculation for the sea can find the suitable design thickness should be 92μm（coated duplex-system）.
If possible, the life-span of the NPP IV may adopt the closed interval 25~28 years. By the decision maker, the most possible life-span of the NPP IV is 26 years, and this result is the cause of the anchor bolts. How does Taipower calculate the loss of the NPP IV? The life-span of the NPP IV may be extended to 45 years, and therefore the loss will be (1 - 26 / 45) x 100% = 42.2%. How does Taipower solve this problem? Taipower must add the quantity of the thermal power plants, and the provided cheaper electivity should compensate the loss of the NPP IV.
References
Let's see the info of the Galvanizing Association of Taiwan, http://www.galtw.org.tw/info.htm, and the relationship of the thickness and life-span can be calculated by the Table 2 and Table 5. In the Table 5, the thickness 53μm is between the grade 50 and 55, and the equilibrium amount of the zinc is 376g/m^2. In the Table 2, the amount of the zinc is in the closed interval 305~488g/m^2, and the equilibrium life-span is in the closed interval 35~50 years for the farm.
The life-span of the thickness 53μm is 40.8 years（coated duplex-system）, and it satisfies the design life-span of the NPP IV. In the general design result, the Factor of Safety should be considered by the designer, especially the extended life-span more than 0.8 year. Actually, the location is near the sea, not the farm. According to the similar calculation, the actual design life-span is 33.1 years for the sea（coated duplex-system）, and it reduces 7.7 years. If the adopted design life-space is extended to 50 years, the similar calculation for the sea can find the suitable design thickness should be 92μm（coated duplex-system）.
If possible, the life-span of the NPP IV may adopt the closed interval 25~28 years. By the decision maker, the most possible life-span of the NPP IV is 26 years, and this result is the cause of the anchor bolts. How does Taipower calculate the loss of the NPP IV? The life-span of the NPP IV may be extended to 45 years, and therefore the loss will be (1 - 26 / 45) x 100% = 42.2%. How does Taipower solve this problem? Taipower must add the quantity of the thermal power plants, and the provided cheaper electivity should compensate the loss of the NPP IV.
References
- 陳文信、蒼弘慈、侯俐安（2013.04.03）綠委：核四上萬支錨栓 無安全認證，中國時報，http://news.chinatimes.com/focus/501013158/112013040300105.html
- 台灣電力股份有限公司（2013.04.03）核四廠HDA型錨栓通過美國機械工程師協會品保制度認證 品質符合核電廠需求，中央通訊社，http://www.cna.com.tw/postwrite/Detail/123641.aspx#.UVxeA6Iya00
- 中華民國熱浸鍍鋅協會，熱浸鍍鋅介紹，http://www.galtw.org.tw/info.htm
- Hilti, Inc.（2011）Hilti Mechanical Anchoring Systems, http://www.buildsite.com/pdf/hilti/Hilti-Mechanical-Anchoring-Systems-624079.pdf
