Tongs triggering method

摘要

A method for controlling and coordinating the operation of a lifting device and a tongs device in removing and disassembling and/or installing and assembling a series of elongate members disposed within a wellbore involves sequentially sensing the presence of a series of joints and automatically triggering the lifting device and tongs device in response thereto. In some examples, the method senses the location of an upper joint to determine when the lifting device should begin decelerating prior to stopping the ascent of a lower joint at a target elevation. In some examples, the method includes control means for automatically skipping various joints.