On a rainy Saturday in March, we performed two 12-inch linestops on the side of two sludge lines inside the NEFCO plant so that existing non-functioning plug valves could be removed and replaced.
As I understand it, the NEFCO plant is the receiver of the sludge from the MWRA Deer Island treatment facility and through a heating process, turns it into bagged fertilizer.
The pipe we were stopping was ductile iron but it had a fiberglass liner, so prior to performing the work, we obtained an old piece from the Owner and performed a test tap at the shop to ensure that the fiberglass would come out clean with the coupon and the fibers would not create a “birds nest” while tapping.
Also, because of the viscosity and amount of material in the sludge, we decided to use linestop fittings with pinned completion plugs instead of the screw in type. That turned out to be a good decision because the stuff I saw when those plug valves were removed was pretty nasty. Andyes, corn never breaks down, neither does panty hose.
As with all interior jobs, most of the time is spent positioning and lifting fittings and equipment and ensuring that everything is lined up because in the end, we have to get those completion plugs installed so that we can get the temporary knife gates back off of the fittings.
The pipe fitters at the NEFCO plant were great to work with. What better place to be on a rainy Saturday in March!
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