Another Look at Pipe Pigging
Although the technology of the hardware of pipeline pigs has been fairly static, the way they are put to use changes quickly.
Just running a poly pig through a pipe and declaring it "clean" is nonsense! When you send an inline inspection tool through the piping system, you expect that your your pig has reduced or eliminated lift off, allowing a more accurate result from magnetic flux leakage inspection. One also expects the pipeline's efficiency to be greatly improved after thorough pigging.
To get the best cleaning and ensure the system's peak condition, it is a must to enlist the services of a qualified pipeline-cleaning service company such as Professional Piping Services, Inc.
The first mechanical pigs were pretty rustic devices thrown together from bailed fabric and barbed wire. The have matured into today's polyurethane (PU or just "Poly") marvels. Each manufacturer will select their own types and ratios of pre-polymers and curing agents that combine to create the castable product with various foam densities, abrasion resistance, elasticities and other variables that impact effectiveness and durability in a given application.
What kinds of Pigs are available?
The kinds of pigs, and the applications they can be used for, are as varied as the piping industry itself. Generally, pigs are are made in sizes with a 1.5 length to diameter ratio. Keeping your bends, or ells, to a minimum of 1.5D is therefore important for them to be easily piggable. Tandem pigs can be used to navigate the tighter ells, if retrofitting an existing system is not an option.In addition to Poly Foam or PU pigs, steel mandrel discs and cups can be used for certain applications.
The Polly foam types are generally made to match the Outside Diameter of the pipe and can navigate tight radius ells, miter bends, "T" intersections, multi-diameter piping systems and reduced port valves. Polly Foam Pigs sometimes incorporate wire strip brushes for more thorough cleaning, a nose pull rope to assist in propulsion, transmitter cavity to install varoius instruments, making it a smart pig, and other accessories as may be required.
When using an ILI, it may be required to provide data before the ILI tool is introduced into the system. This data can be captured using a caliper pig to identify welds, taps, valve, bends, wall thickness and more.
A smart pig was mentioned before, but let me explain. A smart pig (also know as Sherlock Pig) helps re-map the entire system. A pipeline's construction doesn't always match the original plan, so the documents may not provide an accurate picture of the final system. The smart pig can identify lost branches and valves, changes in diameter, and can even specify depth in earth or water.
There is much more to this topic than the author can address at this time. When you need help with your piping system, don't trust me, trust my client, Professional Piping Services, Inc.
The author of this article has referenced source(s) from the internet including an article from pgjonline.com. The client for whom this is written is much more knowledgeable about the topic than the author. Any inaccuracy or error should be attributed to the author, and not the Poly Pig Specialists themselves, or the referenced article(s).
