Modular downhole inspection system for coiled tubing

摘要

A downhole inspection tool is attached to the lower end of a length of coiled tubing having an electrical/fiberoptic cable threaded through the center. The coiled tubing carries a flow of optically clear and/or acoustically homogeneous fluid from a supply of such fluid at the surface. The tool itself includes a cable head subassembly module attached to the lower end of the coiled tubing and terminates the electrical and optical conductors within the cable. An inspection module for producing an electrical signal indicative of downhole conditions is detachably connected to the lower end of the cable head assembly module. An outer flow tube is mechanically connected to the inspection module and surrounds both of the modules to define an annular space therebetween. The flow tube has its upper end fluid coupled to the coiled tubing for conducting the flow of the optically clear and/or acoustically homogeneous fluid down along the annular space and out the lower end of the tool to create a region conducive to inspection by the tool.