A blowtorch, also referred to as a blowlamp, is an ambient air fuel-burning tool used for applying flame and heat to various applications, usually in metalworking, but occasionally for foods like crème brûlée.
Early blowtorches used liquid fuel, carried in a refillable reservoir attached to the lamp.
This type of lamp, with spirit fuel, continued to be in use for such small tasks into the late 20th century.
[2] There remain several manufacturers producing brass blowtorches in India, China and North Korea for markets where propane gas is difficult to obtain or too expensive to be viable.
[3] The blowtorch is commonly used where a diffuse (wide spread) high temperature naked flame heat is required but not so hot as to cause combustion or welding.
Temperature applications are soldering, brazing, softening paint for removal, melting roof tar, or pre-heating large castings before welding such as for repairing.
It is also used in cooking: a butane torch may be used to create the layer of hard caramelized sugar in a crème brûlée.