| 摘要 |
A two-way repeatable flushing device, comprising a flushing member (20) for flushing upwards into the annular space between drill pipe and bore hole wall (or lining pipe). The flushing is ensured by means of a remotely controlled valve and a balanced pressure control by associated valve parts (21, 23) by means of pressure liquid. Thereby there can be ensured a controlled distribution of the flow downwards and upwards respectively, and the hydraulic conditions can thereby be improved by hole cleaning during the drilling operation itself. The solution is particularly of interest for use in particularly complicated, long-range wells having significant paths in a horizontal direction. For these types of wells it has been very difficult traditionally to achieve a satisfactory hole cleaning by means of the flow of liquid in the annular space. The flushing member will ensure a satisfactory hole cleaning as a consequence of improved hydraulic conditions in the annular space. With this a significant profit can be obtained related to both economy, quality and reliability.
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