Interlock system for tubular running tools

摘要

An interlock system for use with casing running tools including, without limitation, casing running tools utilized with rig top drive systems. A pressure circuit is in communication with casing running tool slips and spider assembly slips. The pressure circuit controls the supply of pressure to: (1) release the spider slips only when the casing running tool slips are engaged and supporting the entire pipe string; and (2) release the casing running tool slips only when the spider slips are engaged and supporting the entire pipe string.