Specialised Pipeworks: What is the Type of Welding Needed?

14 February 2019

Just to clarify, specialized pipeworks are those that use singular jointing profiles and/or exotic alloys. They bind together in intricate networks and twist off in unexpected directions, perhaps with an angular offset helping the pipes navigate a particularly difficult section of architecture. Welding those intricate pipeworks, seasoned pros utilize the best possible weld techniques. These methods start with butt welds, then they adapt to accommodate more advanced jointing configurations.

Employing Standard Butt Welds

For a generic pipe-to-pipe joint, one that lacks a flange, butt welding, sometimes known as groove welding, will serve well. Groove welds fuse chamfered pipe ends in place. They fuse circumferential edges, flanges, and fittings. If the T-joints, elbows, or other fitting’s types employ a larger material circumference, a triangle-shaped fillet weld takes the place of a V-shaped butt weld. Picture a steel pipe slotting into a larger elbow joint. As the two parts couple, a fillet weld bonds the inner pipe section to its outer mate.

Specialized Welding Techniques           

For regular pipework, the two above welding methods get the job done every time. They’re the established pipe fusing methods, and there’s a good reason for their industry-standard adoption. Turning to more specialized pipework configurations, there are times when grooves and filets cannot properly seal a tubular joint. The pipe is maybe sealed in a steel channel. It’s a wide-diameter tube, so this is open root work, which simply means there’s a gap between the two segments. Whatever the reason, a more intelligent approach is mandated. Using a GMAW (Gas Metal Oxide Welding) rig, there’s preheating work and a thicker wire to fit in the electrode. That gap has to be filled before the weld can encircle the pipework and produce a discontinuity-free joint.

Multistage Pipework Welding Jobs

Basically, there are specialized pipe forms and job locales that necessitate a more thorough approach. If the alloy or weld location is causing trouble, pulsed MIG welding gear can improve the joint while it simultaneously reduces the time taken to form a circumference-spanning weld. Preheating strategies help, as do large cross-sectional-area metal fillers. Having completed that joint, be it a groove weld or a fillet joint, it’s time to test the completed weld and see if it satisfies whatever pipe welding regulations happen to hold sway.

That last part of the job is best left to a welding inspector. However, that doesn’t mean a welder can’t quickly check his work for flaws. Looking for joint discontinuities, the equipment operator packs away his gear. A liquid dye penetrant is painted or sprayed onto the weld. Used on specialized pipework systems, lines that require uniquely skilled welding techniques, the dye quickly makes a joint imperfection visible to the naked eye.