西藏澜沧江班达水电站水上钻探施工技术

Overwater drilling technology for the Banda Hydropower Station on the Lancang River in Tibet

摘要:

在水上尤其是在水流比较快的江、河上进行钻探施工，与陆地相比，具有施工难度大、危险系数高、钻探效率低等难点。大型水电站往往选在高山峡谷之中，前期勘探条件极为恶劣，水上钻场运送极为困难，而河心孔钻探是一种有效验证河床覆盖层厚度的技术手段，在水电站勘探中通常会遇到。本文根据班达水电站勘探水上钻探工程，介绍该项目水上钻探施工所用的油桶筏制作安装及参数计算和验证,锚固使用的钢丝绳选择及强度验证，江面过渡设备优化设计,保护套管下入方式和垂直度校核，油桶筏转移，覆盖层成孔及取心工艺，坚硬强研磨基岩钻进工艺等关键技术。

Abstract:

Drilling on water, especially on rivers where the water flow is relatively fast, is more difficult than land, with difficulties in construction, high risk factors, and low drilling efficiency. Large hydropower stations are often selected among alpine valleys. The early exploration conditions are extremely bad, and it is extremely difficult to transport on the water drilling site. River core drilling is a technical method for effectively verifying the thickness of the river bed cover, which is usually encountered in hydropower station exploration. This article introduces the construction and installation of the oil drum raft used in the offshore drilling construction of the project and the calculation and verification of various parameters, the selection of anchoring steel rope and strength verification, the optimization design of the river surface transition equipment, and the protection casing The key technologies such as access method and verticality check, oil drum raft transfer, overburden hole formation and coring technology, and hard and strong grinding bedrock drilling technology provide reference for similar projects in the future