초록 ▼

A flame-spray duct defined by the portion of a bore passing through a flame-spray body at the outlet end thereof having a duct L/D ratio of at least 5-to-1 is associated with elements within the flame-spray body which assure nearly uniform flow of reactant oxidant and fuel mixture at the point of in

A flame-spray duct defined by the portion of a bore passing through a flame-spray body at the outlet end thereof having a duct L/D ratio of at least 5-to-1 is associated with elements within the flame-spray body which assure nearly uniform flow of reactant oxidant and fuel mixture at the point of introduction of the particulate material within the duct to eliminate the formation of eddies and recirculation regions thereby preventing uninterrupted even flow of the particulate material from the point of introduction into the duct to the exit from the duct resulting in even heating of the particulate material and where the material is capable of melting, the adherence of molten particulate material on the wall of the duct. The elements within the flame-spray body may take the form of a relatively small diameter oxidizer inlet bore leading to a diverging conical diffuser leading to and emerging with a larger diameter bore section defining the flame-spray duct. Alternatively, the metered flow of oxidant may be passed through a plenum chamber to smooth out the flow of oxidizer prior to its introduction into the flame-spray duct and contact with the particulate material. Uniform flow may further be assured by passing the metered flow of oxidant through a long pipe section of uniform diameter prior to introducing the flow of oxidant into the flame-spray duct.

대표청구항 ▼

In a duct-stabilized flame spray method comprising the steps of feeding a metered flow of a cold fluid oxidant and a fuel into a duct in a flame spray body, mixing the oxidant and the fuel, igniting the flow mixture of said oxidant and fuel to maintain a combustion region within, through, and out of

In a duct-stabilized flame spray method comprising the steps of feeding a metered flow of a cold fluid oxidant and a fuel into a duct in a flame spray body, mixing the oxidant and the fuel, igniting the flow mixture of said oxidant and fuel to maintain a combustion region within, through, and out of sad duct to thereby form a high-velocity, high temperature jet stream extending beyond the exit of the duct in the direction of a workpiece in the path of said jet stream, introducing particulate material to the jet stream at or near the upstream entrance to said duct, and directing the high-velocity particles against said workpiece, the improvement comprising the step of assuring nearly uniform flow of reactant oxidant and fuel mixture at the point of introduction of the particulate material into said duct by having a duct L/D ratio of at least 5-to-1 and by radially introducing the particulate material such that the nearly uniform flow of reactant oxidant and fuel mixture at the point of radial introduction of the particulate material eliminates the formatiion of eddies and recirculation regions preventing uninterrupted, even flow of the particulate material from the point of introduction to the exit end of the duct, and thereby preventing uneven heating of the particulate material.