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chemical cutter

1. n. [Perforating]
A downhole tool run on wireline to sever tubing at a predetermined point when the tubing string becomes stuck. When activated, the chemical cutter use a small explosive charge to forcefully direct high-pressure jets of highly corrosive material in a circumferential pattern against the tubular wall. The nearly instantaneous massive corrosion of the surrounding tubing wall creates a relatively even cut with minimal distortion of the tubing, aiding subsequent fishing operations.