Crossfire burners

The tool used to produce flames suitable for working glass tubes is variously named torch, burner, blowpipe, lamp, cannon, fire and gun. In the interests of simplicity that used for bench work will be referred to as a bench burner or a burner that used in the hand will be called a handlamp or a lamp. The multiple flame type of burner is used in some workshops for bench work and is universally used for working glass in a glassblower s lathe they will be referred to as crossfires and are shown in Plate 4.5. 

There are two types of burners, embracing bench burners, handlamps and crossfires. 

There are a number of burners, lamps and crossfires available. Most of them are designed to burn coal gas-air, coal gas-air-oxygen or coal gas-oxygen mixtures. Such burners are not suitable for use with hydrogen, namral gas or liquid petroleum gases. 

The following bench burners, handlamps, ribbon burners and crossfires have been used by the author and have proved satisfactory. 

The burners should include crossfires as shown in Plate 4.4. Crossfires are excellent for joining large diameter tubes since the heat is applied all round the circumference of the join, and the length of tube heated is no more than that required to effectively melt the glass. 

A bench burner, adapted for attachment to the burner carriage, can be used to work tubing which is too small in diameter for the crossfires, or to heat a greater length of tube than can be conveniently heated with them. 

The choice of flame or flames depends on the available burners. The aim should be to heat a length of the tube equal to about twice the tube diameter. A large flame, from a suitably mounted bench burner, is most satisfactory. Crossfires will also serve provided that the flames are so arranged that the heat is uniformly spread over the required length of tube. 

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