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washover pipe

1. n. [Drilling]
In fishing operations, a large-diameter pipe fitted with an internal grappling device and tungsten carbide cutting surfaces on the bottom. The washover pipe can be lowered over a fish in the wellbore and to latch onto and retrieve the fish. Since the washover pipe is relatively thin-walled and large in diameter, and may be prone to sticking itself, the washover operation is usually reserved as a measure of last resort before abandoning the fish altogether.