“The tools are built to travel inside a gassed pipeline and collect data through sensors as it goes... these sensors are able to detect and assess areas where the pipe wall may be damaged by corrosion or other factors such as a third party contractor,” Elaine Ruiz, Pipeline Integrity Team Lead.
The special tool SDG&E employee Elaine Ruiz is describing is called a PIG. It stands for “Pipeline Inspection Gauge.” These inspection tools are used by Ruiz and the pipeline integrity team to get a closer look at the inside of a natural gas pipeline.
How a PIG helps keep natural gas pipelines safe
A PIG travels inside the pipeline, taking readings around the full circumference of the pipe for the entire length of the run to identify any corrosion, damage to the pipeline, such as dents or gouges inside and out.
“The large number of sensors on the tool will read all around the pipeline internally and externally, measuring the size and depth of any potential damage to the pipeline, so that Pipeline Integrity engineering can make a determination on what type of repair is needed,” according to Ruiz.
She is part of a dedicated pipeline integrity team that performs these types of inspections on large-diameter high-pressure pipelines using advanced safety inspection tools, like pigs. But that’s not all, Ruiz and her team are also behind the design planning of new and existing pipelines that need to be retrofitted and work alongside the construction team as the projects are completed.
These activities compliment those performed by SDG&E’s natural gas transmission and distribution workforce, which proactively performs leak survey and damage prevention activities, including patrolling lines and monitoring contractors digging near pipelines. One of the greatest potential sources for natural gas pipeline damage comes from unsafe digging, which is why it is vital to call 8-1-1 prior to digging.
All of these tasks are part of a comprehensive and proactive gas pipeline safety program that employees like Ruiz follow to ensure we continue to provide safe and reliable service to our customers.
“Technology now allows us to more easily find, analyze and target potential anomalies in our underground system of pipes. This in turn, makes the assessment and remediation work performed by our teams more thorough, and helps to ensure the integrity of the pipelines,” said Ruiz.