| 摘要 |
A whipstock assembly and method of operation is disclosed that automatically orients itself within a wellbore to a known first rotational position. The whipstock assembly is mounted on bearings that permit free rotation of the whipstock assembly within the wellbore. Due to gravitational forces, the eccentric weight load of the whipstock will automatically orient itself on the low side of the wellbore. Most wellbores are angled and the angle, azimuth, depth and other information about the wellbore is known so that the operator will know what position the whipstock assembly will automatically assume. A lower orientation section of the whipstock assembly is clamped into that first rotational position such as by a lower packer and/or slips. The whipstock is then rotated to the desired orientation by reciprocating the wellbore string. The whipstock is then clamped into the desired rotational position by activating an upper packer and/or slips. The running tool is removed and drilling or milling can be initiated. After the new wellbore is completed, the whipstock assembly can be retrieved from the wellbore or relocated to a different borehole depth to be used to drill or mill another new borehole section. |
