The word blowtorch or blow torch has two meanings: In USA usage, it's what in British English usage's called a blowlamp, various types of liquid- or gas-burning tools used for heating. They produce a much larger softer flame than an oxyacetylene torch and are used for low temperature applications - soldering, brazing, melting roof tar, or pre-heating large castings before welding, such as for repairing cast-iron cylinder heads, and for other direct rapid applications of heat such as in cooking.… (
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