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carrying flammable product. Welding engineers and
associated workers must make safety the first priority.
Planning for Safe Execution
Each live welding case can be different, so planning a
site-specific approach is key. First, welding engineers
perform a risk analysis to determine the best approach,
assess all possible scenarios, and create a backup
plan. After successful execution of a weld, more
testing follows – technicians trained in advanced
non-destructive evaluation (NDE) return to the site a
minimum of two days after completion to ensure that
there are no signs of hydrogen cracking.
“To plan the project, we need to know about the
customer’s pipeline condition – the thickness and
operating pressure, for example,” explains Vrolyk.
“We need to figure out what size and type of fitting
to use and where it will be placed. We do a pre-weld
examination with ultrasonic testing to tell how thick
the wall is and make sure it’s clean. We need to
assess the hardness of the material to make sure we
use the right procedure.”
Trained to Combat Delayed Cracking
Of course, safety regulations often include
certifications and training standards for the
engineers and other workers performing the
welding procedures. “We’re continually training
in both the classroom and field to avoid burn-
through and hydrogen cracking,” states Vrolyk.
“We conduct special engineering software
simulations and mockups in the shop before
projects to ensure that everyone is well prepared.”
Although live welding is used for most
pipeline procedures, it’s difficult for pipeline
companies to carry the expertise in-house. Most
operators rely on specialized providers to perform
the service because they know how to work within
government safety regulations and have the
extensive training and special equipment required
for success.
More than hydrogen cracking caused the 1992
Calgary incident, but it serves as an example that
even everyday tasks like welding deserve special
attention to safety.
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