The piping for fuel, chemical transport, water supply, and cooling needs is typically very complex and subject to high temperatures and pressures. Shutting down entire lines is often impossible so practical realities dictate plants operate continuously. Downtime is simply unacceptable so it is necessary to plug a pressurized pipeline.
“A great deal of what we do is in mills and chemical plants, and we need a may options in situations that call for a hot tap,” explains Tom Bowling, P.E., Principal Engineer for Team Industrial Services, Inc., based in Alvin, Texas.
Hot Tap Plugging or ‘Bagging’ is the insertion of an Inflatable Line Stop Plug into an active pipe, via a tapping saddle or nozzle, and inflating with a gas or liquid so that it fills the line. Bowling has been using Petersen Inflatable Multi-Flex™ Pipe Plugs and the Hot Tap Pipe Plug Insertion System from Petersen Products since 1999. He explained that in 1999 he had a call from Duke Power—they wanted to plug a 42-inch line located 12 feet under the basement of a nuclear power plant.” And while he was preparing for that work, another call came in from a refinery in Southern Louisiana: two banks of exchangers were operating, but one was contaminated by leaking gas. To fix the leak and keep at least one exchanger bank working, Team Industrial would have to plug a 16-inch inlet under 180 psi, with temperatures up to 230ºF.
Both projects went well according to Bowling. At the Louisiana refinery “we filled the Petersen inflatable Line Stop Plug “bag” with diesel,” he says, “that way, if there was a leak, there wouldn’t be contamination but the bag was in for the six months and didn’t fail.” Plugging the nuclear power plant line also went smoothly, and the plug was kept in place for a week before being pulled.
Since then, Bowling estimates he’s used the Petersen inflatable Line Stop system 40-50 times, almost always custom fabricated to plug lines up to 60-inches in diameter. They are also useful when lines are out of round or uneven internally due to scaling or buildup, because the rubber adheres to a larger area and adjusts to irregularities.
Petersen has also produced Inflatable Tunnel Seals up to 21 feet in diameter to isolate sections of a mine.
Team Industrial Services, Inc.: www.teamindustrialservices.com, 800.662.8326 (281-331-6154)
Petersen Products Co., LLC: www.pipeplug.com, 800.926.1926 (262.692.2416)