A pigtail is a coiled or looped section of tubing used in piping and instrumentation systems to absorb vibration, manage thermal expansion, and protect pressure instruments from direct exposure to process media. Moreover, its curved design allows it to flex under temperature or pressure changes. The most basic definition is that pigtail siphons are a type of siphon that is nothing more than a looped pipe, in this case in a spiral similar to a pigtail, hence its name, although sometimes it is also used the name lyre type siphon or just lyre. These siphons are installed in vapor pressure. This is where a pigtail syphon comes in, acting as a protection nett to ensure the accuracy and lifespan of these essential instruments. It is formed in a circular or coiled shape. This shows a few modes from 1/4" to 1/2" made up with isolating ball valves and pressure gauges.
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