It's a bit cliché to kick off a story about NASA with "Houston, we have a problem," but seriously, they've got a problem: the plumbing on the International Space Station is clogged, and NASA isn't exactly sure why, or how to fix it. To clarify, it's not the actual toilet component that's broken, but the $250 million system designed to recycle astronauts' urine, sweat, and exhaled vapor into clean, potable water.
Engineers working on the problem believe high concentrations of calcium in the astronauts' urine is causing deposits to build up, clogging the system that provides up to two-thirds of the water used on the station.
This is a weld-on tank bung; a means of attaching pipe threads to a vessel. It is intended to be welded onto the wall of a tank or pressure vessel, providing solid pipe threads in a material typically too thin to be tapped for pipe threads. On some occasions I've used them for that purpose. On others, I've found that they make a great component in pneumatic cannons. More on this obscure part after the jump.