An oxygen cutting process that uses heat from an oxyfuel gas flame, with iron or other metal powder to aid cutting.

The metal powder cutting process is a technique for supplying an oxyfuel cutting torch with a stream of iron-rich powered material. Iron powder and mixtures of metallic powders, such as iron and aluminum, are used. The powdered material promotes and accelerates the oxidation reaction and also the melting and spalling action of hard-to-cut materials. The powder is directed into the kerf through either the cutting tip or

single or multiple jets external to the tip. When the first method is used, gas-conveyed powder is introduced into the kerf by special orifices in the cutting tip. When the powder is introduced externally, the gas conveying the powder imparts sufficient velocity to

the powder particles to carry them through the preheat envelope into the cutting oxygen stream. Their short time in the preheat envelope is sufficient to produce the desired reaction in the cutting zone.

Some of the powders react chemically with the refractory oxides produced in the kerf and increase their fluidity. The resultant molten slags are washed out of the reaction zone by the oxygen jet. Fresh metal surfaces are continuously exposed to the oxygen jet

and powder.

Cutting of oxidation-resistant steels by the powder cutting method can be done at approximately the same speeds as oxygen cutting of carbon steel of equivalent thickness. The cutting oxygen flow must be slightly higher with the powder process.

Powder is dispensed from a hopper by a controllable vibratory device, and delivered through a hose to the torch. The other type of dispenser is a pneumatic device coordinated with a fluidizing unit. The powder is picked up by a gas stream that serves as the transporting medium to the torch. A special manual powder cutting torch mixes the oxygen and fuel gas and then discharges this mixture through a cutting tip with multiple orifices. The powder valve is an integral part of the torch.

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