(Redirected from Blowtorch)
A 'blow torch' is a simple
heating
torch, which burns
fuel with ambient
atmospheric air. In the
United Kingdom the older, kerosene-fuelled, type was called a 'blowlamp'.
LPG fuel
Modern blow torches will typically run on
propane or
butane cartridges, or be fed from a
liquid petroleum gas cylinder via a hose. 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 direct rapid application of heat in
cooking. They cannot be used for welding, but find many other uses, not least because in their simplest form of a disposable canister feeding a hand-held torch they are very cheap and highly portable, and because the LPG fuel is very cheap in comparison to
acetylene and
oxygen.
Liquid fuel

An old-fashioned kerosene blowtorch
Older blowtorches used liquid fuel such as
kerosene in the form of
paraffin oil, or
gasoline and more recently biodiesel. These are largely redundant, and may be difficult to start, requiring pre-heating with
methylated spirit. If any doubts exist as to the integrity of the
pressurized fuel tank or any of the seals in the torch, it should be treated strictly as an antique — if the tank bursts there is a very real risk of
explosion or
fire.
See also
★
Propane torch
★
Oxy-fuel welding and cutting
★
Gas burner