Horizontal Directional Drilling
| Most pipelines are bury along the road side, but the method will be adopted the horizontal directional drilling (HDD) when it meets the river, freeway, underground obstacle, special protection area. HDD method was used first in Taiwan in 2001. |
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| HDD drilling diameter is about 200 ~ 1200mm and is applied to clay or sand with STP value lower 30, or gravel with concentration lower 30% and diameter lower 15cm. Under the consideration of cable length manufacturing, road deliver length, cable joint, voltage, tension and lateral pressure, the HDD drilling length usually is about 200~400 m. Jenyi completed several Taiwan power company HDD project such as Hsiping ~ Nanping, Meishan ~ Chiuchu, Kaohsiung ~ Neiwei, inpien~ Hsiaoliuchiu and Ta-peng ~Tung-kang since 2000. The special project is Linpien~ Hsiaoliuchiu, it located in seacoast of Hsiaoliuchiu island. |
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These following season shall be considered: 1) ensuring safety of drilling across seacoast embankment structure. 2) chemical character and pressure of sea water will affect the ration of stabilizing liquid. 3) hole stabilization when drilling expanding. 4) preciously sea positioning. 5) driver |