Wedge
Wedge turns up in 2 fields: valves, geosynthetics. Here is what it means to the people in each one.
Wedge in valves
The tapered closure member of a gate valve that is driven down between two inclined seats to seal.
Solid wedges are one rigid piece; flexible wedges are cut around the rim so they can flex slightly and still seal when the body distorts with heat or pipe load; split wedges are two halves that align themselves to the seats. The wedge shape gives mechanical seating force, which is also why a hot valve closed tight can lock the wedge in place when it cools.
"Solid wedge on that steam gate is stuck in the seats, we're going to need heat and a big wrench to break it loose."
Wedge in geosynthetics
Installer shorthand for the hot wedge welder, or for the heated wedge inside it.
The wedge is a heated metal blade that the machine drives between the two overlapped sheets, melting their surfaces just ahead of the pinch rollers. Crews say running the wedge for making fusion seams and treat wedge temperature and speed as the two settings they adjust most. Dirt or moisture between the sheets, or a worn wedge, shows up as cold spots and weak peels.
"Bump the wedge up ten degrees and slow it down a hair, the peels are coming off the inside track."