Internal Robotic Inspection Tool for Unpiggable Pipe Inspections

A self-propelled in-line inspection tool tested at Electric Power Research Institute and utilized in Europe can traverse a complex piping configuration and discriminate areas of metal loss. This tool is becoming available to inspect traditionally unpiggable piping such as: buried piping at nuclear plants, oil and gas terminals, refineries, industrial sites, cased pipeline crossings and distribution pipelines. In the past, these facilities have often deferred their inspections due to the cost to modify facilities for traditional flow driven in-line inspection tools or the cost to excavate to complete direct examination. A new line of tools being introduced by GE Energy's Industrial Solutions business, is becoming available with Single Point Access capabilities. This technology allows the tools to be inserted into the pipe at a single location, e.g. a removed block valve, and retrieved from the same location. In many cases, facility modifications and limited excavations are not required or necessary to complete the inspections.

The first of this new line of robotic tools is capable of running in pipes that are filled with liquid, partially filled with liquid, or dry. This tool was recently included in blind testing at Electric Power Research Institute (EPRI). The test mockup consisted of three sections of 24-inch pipe. Two sections were 40 feet long and the third was 60 feet long with a 90-degree 1.5D elbow. In order to simulate field conditions, the entire test pipe was covered so that all of the testing was completed blind.

Figure 1. Tool inserted at removed valve