BLOW TORCH

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'.

Contents

LPG fuel

Liquid fuel

See also

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

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