The Importance of Welding Inspection and Maintenance on Pipe Projects

28 April 2017

Heat treated pipes are rolled and welded. They’re even pressure-rated, certified as being able to reliably handle a specified fluid. Weld technology binds the sections together. It also creates the all-important joints for pipeline flanges. Every one of these welds is a potential weak spot on a pipe project, a possible chink in the armoured line that could cause a catastrophic leak. Welding inspections and maintenance procedures exist to detect such fabrication flaws.

Stressing the Importance of Weld Inspection

A number of non-destructive techniques dominate pipe project welding examinations. There are X-Ray tests, ultrasonic tests, and other surface-penetrating instruments. They pick up interior flaws, then create an image of the subsurface weld defect that’s easy to interpret. It’s a refined science, but why is the inspection so important? Well, pipe welds securely join pressurised conduits together, and those joints must be as sound as any other part of the pipeline. There are codes to make sure the welds meet certain quality standards, but what if the weld only meets those requirements on the surface? What happens then? If we’re talking about water, the pipe will eventually leak. The weeping joint will make the ground swampy, cause a ceiling to sag and collapse, and create an expensive month-end water bill. As a worst case scenario, though, there are gas pipes and oil lines, fuel conduits and corrosive chemical lines. A substandard weld that cracks on one of these pipe projects, well, the leaking fluid could cause a fire, perhaps an explosion.

Clarifying Pipe Project Maintenance

The heat processed pipes are certified at the fabrication facility, so rolled metal reliability is assured. Visual inspections and non-destructive test procedures work in-situ as a quality assurance mechanism, a work guarantor that reinforces the welders’ labours. Next, time is on the side of fatigue and part’s degeneration, so a predictive maintenance program is needed to examine the pipe welds. This scheduled upkeep strategy finds tiny discontinuities before they become full-blown flaws. Beyond joint integrity, this job involves taking care of business further down the line. External and internal stress factors are found and corrected in this manner, so excess material tension won’t propagate along the pipe and deform the weld.

Numerous codes and guidelines exist as pipe project checks and counter-checks. They approach this important discipline from a quality assurance angle, so weld techniques and weld materials always adopt a best practise methodology. From there, invisible flaws and potential material discontinuities are unlikely but not impossible. Even an extreme unlikelihood isn’t tenable in this situation, though, not when pipe project welds are responsible for flange integrity, line branch continuity, and all of the extended pipe sections that contain potentially dangerous fluids.