Patent Application
20120032002
The present disclosure relates generally to a gas cutting torch and more particularly to a tip assembly of a gas cutting torch having an improved mixer.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Oxy-fuel cutting torches, or gas cutting torches, generally employ oxygen and a fuel gas, such as acetylene or propane, by way of example, to cut a workpiece. More specifically, preheat oxygen and the fuel gas are mixed and ignited to provide heat to the workpiece, and then additional oxygen, commonly referred to as cutting oxygen, is added to react with the heated workpiece. This reaction of the cutting oxygen with the heated workpiece initiates sufficient heat and momentum of the gases to initiate a cutting process.
The cutting torch may be a premixed or a postmixed type torch. In a premixed torch, preheat oxygen and fuel gas are mixed within the torch head before being discharged for ignition. In a postmixed cutting torch, the preheat oxygen and fuel gas are discharged from the torch in unmixed streams. Turbulence in the discharged streams mixes the oxygen and fuel gas before ignition occurs. An advantage of the postmixed cutting torch is that postmixed cutting tips produce a longer heat zone than premixed tips, which permits the postmixed torches to operate farther from the work, decreasing the heat stress on the torch and increasing the service life of the tip.
With their inherent drawbacks, improved designs are desired in the field of premixed gas cutting torches. Moreover, ways in which to increase the lifetime of the premixed tip and provide a more compact tip design and thus reduce costs are also desirable.
In one form, the present disclosure generally provides a tip assembly for use in a gas torch comprising a tip and a mixer. The tip has a tip central gas passageway and a distal orifice and the mixer has a proximal end portion and a distal end portion. The distal end portion of the mixer is adapted for connection to the tip and the proximal end portion of the mixer defines a connecting member that removably connects the mixer to a torch head.
In another form of the present disclosure, a gas torch is provided that comprises a torch head and a tip assembly secured to the torch head. The tip assembly includes a tip having an outer tip portion defining a central cavity and a distal orifice and an inner tip portion disposed within the central cavity of the outer tip portion. The inner tip portion defines an outer surface, a tip central gas passageway in communication with the distal orifice of the outer tip portion, and at least one intermediate gas passageway extending from the outer surface to the tip central gas passageway for a flow of at least one gas to provide improved cooling to the tip. A mixer is secured to the tip and the torch head and includes a proximal end portion and a distal end portion. The distal end portion of the mixer is adapted for connection to the tip and the proximal end portion of the mixer defines a connecting member that removably connects the mixer to the torch head. A locking ring connects the tip and the mixer to the torch head.
In yet another form of the present disclosure, a gas torch is provided that comprises a torch head and a mixer having a proximal end portion and a distal end portion. The distal end portion of the mixer is adapted for connection to a tip and the proximal end portion defines a connecting member that removably connects the mixer to the torch head.
In still another form, the present disclosure provides a method of cooling a tip of a tip assembly of a gas torch. The tip assembly includes a mixer connected to the tip and the tip and the mixer are secured to a torch head of the gas torch. The method comprises directing a flow of a first gas and a flow of a second gas to a mixer central gas passageway of the mixer; directing the flow of the mixed first and second gases from the mixer to an axial passageway of the tip; directing a flow of a third gas to an outer passageway of the tip; directing the flow of the third gas inwardly through at least one intermediate gas passageway; directing the flow of the third gas to a tip central gas passageway of the inner tip; and directing the flow of the mixed first and second gases and the flow of the third gas distally through a distal portion of the tip.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
a is a partial cross-sectional view of a typical tip of a gas torch known in the art;
b is a perspective view of the tip of
a is a partial cross-sectional view of one form of a tip for use in a gas torch constructed in accordance with the principles of the present disclosure;
b is an alternate partial cross-sectional view of the tip of
a is a partial cross-sectional view of another form of a tip for use in a gas torch constructed in accordance with further principles of the present disclosure;
b is a perspective view of the tip of
a is a partial cross-sectional view of the tip assembly of
b is a partial cross-sectional view of the tip assembly of
The following description is merely exemplary in nature and is in no way intended to limit the present disclosure, its application, or uses. It should be understood that throughout the description and drawings, corresponding reference numerals indicate like or corresponding parts and features.
Referring to
Various forms of an improved tip for use with a gas cutting torch designed for enhanced cooling are disclosed herein and in U.S. patent application entitled, “Gas Cutting Tip with Improved Flow Passage” to MacKenzie et al. (filed concurrently herewith under Attorney Docket No. 13386-059), the entire contents of which are incorporated by reference herein. Referring to
a-b illustrate one form of a tip 122 in accordance with the teachings of the present disclosure. The tip 122 includes a proximal end portion 114 which attaches to the torch head 21 of the gas cutting torch 20 and a distal end portion 115 through which the gas exits to perform the cutting operation. In this form, the tip 122 comprises an outer tip portion 124 having a proximal portion 126 and a distal portion 128. The outer tip portion 124 defines an outer surface 130 and an inner surface 132 and further defines a central cavity 134 and a distal orifice 136. An inner tip portion 140 is disposed within the central cavity 134 of the outer tip portion 124. In one form, the outer tip portion 124 and the inner tip portion 140 are separate components. In another form, the outer tip portion 124 and the inner tip portion 140 are unitarily formed as a single piece by any suitable means in the art, such as, e.g., lost-wax casting.
The inner tip portion 140 has a proximal portion 142 and a distal portion 144 and defines an outer surface 146 and an inner surface 148. The inner tip portion 140 further defines a central gas passageway 150 having a proximal end portion 152 generally occluded by a component of the gas cutting torch 20 extending to a distal end portion 154 in fluid communication with the distal orifice 136 of the outer tip portion 124. Additionally, the inner tip portion 140 defines at least one intermediate gas passageway 156 extending from the outer surface 146 of the inner tip portion 140 to the central gas passageway 150 for the flow of at least one gas to provide improved cooling to the tip 122, as described in further detail below. More specifically, in one form of the present disclosure, a plurality of intermediate gas passageways 156 extends between the outer surface 146 of the inner tip portion 140 and the central gas passageway 150.
As shown in
The tip 122 is attached to the torch head 21 of the gas cutting torch 20 by any suitable means known or contemplated in the art. For example, the torch head 21 may have external threads for receiving a threaded tip nut for connecting the tip 122 to the torch head 21. Alternatively, in another form of the present disclosure, a tip seat may be secured to the torch head 21 and the tip 122 secured to the tip seat by way of a locking nut. The gas cutting torch 20 generally includes a plurality of internal gas supply tubes for the flow of preheat oxygen, fuel gas, and cutting oxygen and the torch head 21 generally includes a plurality of passages in fluid communication with the gas supply tubes and through which the preheat oxygen, fuel gas, and cutting oxygen flow and enter the tip 122.
In operation, preheat gas, e.g., mixed preheat oxygen and fuel gas (i.e., acetylene, propane, liquid petroleum, or natural gas) flows from a passage within the torch head 21 (or from a mixer, as discussed in further detail with respect to
Accordingly, cutting oxygen does not flow from the torch head 21 straight through the central passageway 150 of the tip 122 as in the traditional tip 10 of
In
In one form, the inner tip portion 140 includes at least one raised ridge or rib 170 extending along at least a portion of the outer surface 146 of the inner tip portion 140 and at least one flute disposed adjacent the rib 170.
Further, the inner tip portion 140 is conductive and is adapted for electrical connection to an ignition system of the gas torch 20. An ignition wire (not shown) from an ignition system extends through the tip 122 and is in electrical contact with the conductive inner tip portion 140 and thus generates the spark for ignition of the gas cutting torch 20.
Referring to
In operation, the axial passageway 366 receives preheat gas from a passage in the torch head 21. The central gas passageway 350 receives cutting oxygen via the intermediate gas passageways 356 in fluid communication with a cutting oxygen passage within the torch head 21. Similar to the tip 122 of
Referring now to
The tip 422 includes an outer tip portion 424 having a proximal portion 426 and a distal portion 428. The outer tip portion 424 defines an outer surface 430 and an inner surface 432 and further defines a central cavity 434 and a distal orifice 436. An inner tip portion 440 is disposed within the central cavity 434 of the outer tip portion 424. In
The inner tip portion 440 has a proximal portion 442 and a distal portion 444 and defines an outer surface 446 and an inner surface 448. The inner tip portion 440 defines a central gas passageway 450 having a proximal portion 452 generally occluded by a component of the gas cutting torch, i.e., the mixer 480, as described in further detail below. The central gas passageway 450 extends from the proximal portion 452 to a distal portion 454 in fluid communication with the distal orifice 436 of the outer tip portion 424. Additionally, the inner tip portion 440 defines at least one intermediate gas passageway 456 extending from the outer surface 446 of the inner tip portion 440 to the central gas passageway 450 for the flow of at least one gas to provide improved cooling to the tip 422, as described in further detail below.
As best illustrated in
The tip assembly 408 further includes a mixer 480 for mixing preheat oxygen and fuel gas to form a preheat gas mixture. As illustrated in
The mixer 480 defines an outer surface 488 and an inner surface 490 and a plurality of internal gas passageways, including a central gas passageway 492, a plurality of proximal gas passageways 494, and a plurality of distal gas passageways 496. In this form, the central gas passageway 492 extends from a proximal end 491 at the proximal end portion 482 of the mixer 480 to a distal end 493 proximate the distal end portion 484 of the mixer. The plurality of proximal gas passageways 494 extend from the outer surface 488 of the proximal end portion 482 of the mixer 480 to the central gas passageway 492. In
The plurality of distal gas passageways 496 extend from the distal end 493 of the central gas passageway 492 to the outer surface 488 of the distal end portion 484 of the mixer 480. In this form, the distal gas passageways 496 extend at an angle between the central gas passageway 492 and the outer surface 488 of the distal end portion 484 of the mixer 480.
As illustrated in
The torch head 421 generally includes a plurality of passages in fluid communication with gas supply tubes within the gas cutting torch 20. As illustrated in
The tip 422 and the mixer 480 are connected to the torch head 421 such that the cutting oxygen passage 473 and the proximal annular passageway 460 of the tip 422 are in fluid communication; and such that one of the preheat oxygen passage 475 and the fuel gas passage 477 is in fluid communication with the central passageway 492 of the mixer 480 and the other one of the preheat oxygen passage 475 and the fuel gas passage 477 is in fluid communication with the proximal gas passageways 494 of the mixer. In
In operation, preheat oxygen and fuel gas (i.e., acetylene, propane, liquid petroleum, or natural gas) are mixed within the mixer 480 to form preheat gas. More specifically, preheat oxygen flows from an internal preheat oxygen supply tube within the gas torch 20 into the preheat oxygen passage 475 via the preheat oxygen inlet bore 474. The preheat oxygen flows through the preheat oxygen passage 475 and the recess 423 formed within the torch head 421 and enters the proximal end 491 of the central gas passageway 492 of the mixer 480. The fuel gas flows from an internal fuel gas supply tube within the gas torch 20 into the fuel gas passage 477 via the fuel gas inlet bore 476. The fuel gas flows through the fuel gas passage 477 within the torch head 421 and enters the central gas passageway 492 of the mixer 480 via the plurality of proximal gas passageways 494. The preheat oxygen and the fuel gas mix within the mixer 480 as they flow together through the central gas passageway 492. The mixed preheat gas then flows from the mixer 480 to the at least one axial gas passageway 466 via the angled distal gas passageways 496. The preheat gas flows through the axial passageway 466 into the distal annular gas passageway 462 and exits the distal portion 415 of the tip 422 for the discharge of preheat gas from the torch.
Additionally, cutting oxygen flows from an internal cutting oxygen supply tube within the gas torch 20 into the cutting oxygen passage 473 via the cutting oxygen inlet bore 472. As illustrated in
Accordingly,
Additionally, the mixer 480 of the tip assembly 408 defines a distended length and allows for a tip 422 having a reduced length. Thus, the mixer 480 and the tip 422 having an improved flow passage provide a premixed tip having a more compact design. Further, the enhanced cooling effect of the improved flow passage of the premixed tip 422 of the present disclosure has a similar effect as the longer heat zone in postmixed tips, i.e., decreases the heat stress on the torch and increases the life of the consumable tip.
The present disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the present disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure.
