Method and system for improving a contact tip of a welding assembly

Abstract

A method for improving a contact tip for a welding assembly including providing a contact tip that extends along an axis between a proximal end and a distal end. The contact tip has an axial channel with a channel diameter. The method also includes forming an axial bore with a bore diameter at the distal end of the contact tip. The bore diameter is larger than the channel diameter. The method also includes cutting a length of a rod. The rod has a rod diameter that is substantially the same as the bore diameter. The method also includes inserting the length of the rod in the bore. The method also includes creating a passage through the rod that has a passage diameter that is approximately the same as the channel diameter. The method also includes passing a welding wire through the channel and the passage.

Description

METHOD AND SYSTEM FOR IMPROVING A CONTACT TIP OF A WELDING ASSEMBLYCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This PCT International Patent Application claims the benefit of and priority to U.S. Provisional Patent Application Serial No. 63 / 546,321, filed October 30, 2023, titled “Method Of Improving A Welding Tip,” the entire disclosure of which is hereby incorporated by reference in its entirety.BACKGROUND OF THE DISCLOSURE1. Field of the Disclosure

[0002] The present disclosure relates to systems and methods for welding. More particularly, the present disclosure relates to a system and method for improving a tip of a welding assembly, such as a gas metal arc welding assembly.2. Related Art

[0003] This section provides background information related to the present disclosure which is not necessarily prior art.

[0004] Welding is a method of joining metal work pieces. Arc welding is a commonly used type of welding which involves the joining of metals via an electric arc. An arc welding assembly typically includes a welding gun which has a contact tip that is connected to a power supply. One of the work pieces is also connected to the power supply such that when the contact tip is positioned against the work piece, a circuit is completed between the power supply and the work piece to cause an electrical current to flow through the electrode and the work piece. The electrical current produces a high-temperature arc between the electrode and the work pieces, which melts the work pieces in the regions of the arc to thus weld the work pieces to one another upon cooling.

[0005] Gas metal arc welding (GMAW) is a specific type of arc welding which uses a metal wire as the electrode. The wire is shielded from contaminants by an inert gas, and themetal wire acts as a filler for the weld. A common issue with GMAW assemblies is that a contact tip which surrounds the metal wire can suffer wear. Material costs associated with replacing contact trips can be expensive, and the replacement process can lead to significant downtime from welding operations.

[0006] There remains a need for improvements to systems and methods of welding.SUMMARY OF THE DISCLOSURE

[0007] According to an aspect of the disclosure, a method for improving a contact tip for a welding assembly is provided. The method includes providing a contact tip that extends along an axis between a proximal end and a distal end. The contact tip has a channel that extends between the proximal and distal ends for receiving a welding wire. The channel has a channel diameter. The method also includes forming a bore at the distal end of the contact tip along the axis. The bore has a bore diameter that is larger than the channel diameter of the channel. The method also includes cutting a length of a rod. The rod has a rod diameter that is substantially the same as the bore diameter of the bore of the contact tip. The method also includes inserting the length of the rod in the bore at the distal end of the contact tip. The method also includes creating a passage through the rod that has passage diameter that is approximately the same channel diameter of the contact tip. The method also includes passing a welding wire through the channel of the contact tip and the passage of the rod.

[0008] According to another aspect of the disclosure, a contact tip for a welding gun includes a body that extends along an axis between a proximal end and a distal end. The body also defines a channel that extends between the proximal and distal ends for receiving a welding wire. The channel has a channel diameter. A bore is located at the distal end of the contact tip along the axis. The bore has a bore diameter that is greater than the channel diameter of the channel. A rod is positioned in the bore of the contact tip. The rod defines a passage that extends axially along the axis.

[0009] The rod positioned at the distal end of the contact tips allows worn material of the contact tip to be replaced with unworn and stronger material of the rod, thus allowing the contact tip to be re-used, thereby prolonging a usable life of the contact tip. Additionally, the method of boring the contact tip and inserting the rod may be done quickly and cheaply inhouse, with minimal tools and minimal material usage, thus reducing downtime of welding operations when fixing / improving the contact tip.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] These and other advantages of the present disclosure will be more readily understood by reference to the following description in combination with the accompanying drawings wherein:

[0011] FIG. 1 is a schematic diagram of an example gas metal arc welding assembly;

[0012] FIG. 2A is a perspective view of a first embodiment of a contact tip of an electrode of a welding assembly according to an aspect of the disclosure;

[0013] FIG. 2B is a perspective, cross-sectional view of the first embodiment of the contact tip;

[0014] FIG. 2C is a top view of the first embodiment of the contact tip;

[0015] FIG. 3 is a front view of a metal rod for being inserted into a bore of the contact tip;

[0016] FIG. 4A is a perspective view of the first embodiment of the contact tip, during a first step of improving a worn contact tip;

[0017] FIG. 4B is a perspective view of the first embodiment of the contact tip, during a second step of improving a worn contact tip;

[0018] FIG. 4C is a perspective view of the first embodiment of the contact tip, during a third step of improving a worn contact tip;

[0019] FIG. 4D is a perspective view of the first embodiment of the contact tip, during a fourth step of improving a worn contact tip;

[0020] FIG. 5 A is a perspective view of a second embodiment of the contact tip;

[0021] FIG. 5B is a perspective, cross-sectional view of the second embodiment of the contact tip;

[0022] FIG. 6A is a perspective view of a third embodiment of the contact tip;

[0023] FIG. 6B is a perspective, cross-sectional view of the third embodiment of the contact tip;

[0024] FIG. 7 is a perspective view of a fourth embodiment of the contact tip; and

[0025] FIG. 8 is a flow diagram illustrating a method for improving a contact tip for a welding assembly.DETAILED DESCRIPTION OF THE ENABLING EMBODIMENTS

[0026] Example embodiments will now be described more fully with reference to the accompanying drawings. In general, the subject embodiments are directed to welding systems and methods. However, the example embodiments are only provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0027] Referring to the figures, wherein like numerals indicate corresponding parts throughout the several views, a welding assembly 10 for welding metal work pieces 12 isgenerally shown. More particularly, embodiments of an improved contact tip 25 A, 25B, 25C,25D for a welding gun 22 of a welding assembly, such as a gas metal arc welding assembly, are shown.

[0028] FIG. 1 presents a welding assembly 10 that has a control housing 14. The control housing 14 includes a power source 16 for powering the welding assembly 10. The power source 16 has a first terminal 18 and a second terminal 20. One of the terminals 18, 20 is a positive terminal 18 and the other of the terminals 18, 20 is a negative terminal 20.

[0029] The welding system 10 also includes a welding gun 22 for welding. The welding gun 22 has a handle 24 for being gripped by an operator, and a welding tip region 26 that has a contact tip 25 for contacting the workpiece 12 during welding to create the weld. A neck 27 connects the handle 24 and the welding tip region 26.

[0030] The system 10 also includes a spool 28 of an electrode wire 30 for being supplied to the welding gun 22 through the handle 24 and neck 27 and out of the tip region 26 to serve as an electrode during welding. A wire feeder 32 is coupled to the control housing 14 and the electrode wire 30 for feeding the electrode wire 30 to the welding gun 22.

[0031] A gas source 34 (e.g., a cylinder) that contains a gas (e.g., an inert gas such as argon) is connected to the welding gun 22 for being expelled from the tip region 26 of the welding gun 22 during welding for shielding molten metal from outside contaminants during welding. A gas line 36 extends from the gas source 34 to the control housing 14 and to the welding gun 22 for providing the gas to the welding gun 22.

[0032] A first power cable 38 extends from one of the first and second terminals 18, 20 of the power source 16 and through the handle 24 of the welding gun 22 and is electrically connected to the electrode wire 30 to provide a current to the electrode wire 30.

[0033] The system 10 also includes a conductive clamp 42 for being clamped to the work piece 12 during welding. A second power cable 40 extends from the other of the firstand second terminals 18, 20 to the clamp 42 for completing a circuit between the electrode wire 30 and the work piece 12 during welding.

[0034] The welding gun 22 further includes one or more activation devices 44, such as a trigger 44, button, switch, or the like for permitting an operator to control the supply of the electrode wire 30 to the welding gun 22, to control a supply of power from the power source 16 to the welding gun 22, and / or to control a supply of gas to the welding gun 22 from the gas source 34.

[0035] Embodiments of an improved contact tip 25A, 25B, 25C, 25D of the welding gun 22 and methods for making the contact tip 25A, 25B, 25C, 25D are provided. FIGS. 2- 4D show a first embodiment of the contact tip 25 A. The contact tip includes a body 27 that extends along an axis A between a proximal end 46 and a distal end 48. The body 27 defines a channel 50 that extends axially from the proximal end 46 for receiving a welding / electrode wire 30. As shown in FIG. 2B, the channel 50 has a channel diameter De. As a result of an improving process according to the subject disclosure, the contact tip 25 A also defines a bore 52 at the distal end 46 of the contact tip 25 along the axis A. The bore 52 is aligned with and connected to channel 50 along the axis A. The bore 52 has a bore diameter DB which is larger than the channel diameter De. According to the preferred embodiment, the bore 52 has a diameter of approximately 1 / 8 of an inch but could have other diameters depending on specific applications.

[0036] A metal rod 54 is positioned in the bore 52. The metal rod 52 has a length that is approximately the same as that of the bore 52 such that an end of the metal rod 54 is aligned with the distal end of the contact tip 25A. furthermore, the metal rod 52 has a rod diameter DR that is approximately the same as the bore diameter DB, such that the metal rod 52 is fixed within the bore 52 via an interference fit. The metal rod 52 could also be attached to the contact tip 25A in the bore 52 via other connections, such as an adhesive. According tothe preferred embodiment, the rod 54 is of a metal composition of refractory metals tungsten, molybdenum and tungsten carbide combined with copper, such as an elkonite® material. This material is beneficial because of its degree of hardness which makes the rod 54 resistant to wear. Other metals may be used based on specific applications. The metal rod 52 also has a passage 56 that extends axially through the metal rod 52 in alignment with the channel 50. As will be described in further detail below, the metal rod 52 allows worn material of the contact tip 25 to be replaced with unworn and stronger material of the metal rod 52, thus allowing the contact tip 25 to be re-used and thereby prolonging a usable life of the contact tip 25.

[0037] A second embodiment of a contact tip 25B is shown in FIGS. 5 A and 5B, a third embodiment of a contact tip 25C is shown in FIGS. 6A and 6B, and a fourth embodiment of the contact tip 25D is shown in FIG. 7. These embodiments have generally the same arrangement of components as the first embodiment, but are shaped differently.

[0038] As set forth in the flow diagram of FIG. 8, a method 100 for improving a contact tip 25 for a welding assembly 10 is provided. As illustrated in FIG. 4A, the method 100 includes 102 providing a contact tip 25 A which does not yet include a metal rod 54. The contact tip 25A at this stage may be a worn contact tip 25A after use in welding operations, or a contact tip 25 that has not yet been used / worn. In either case, the described method can be used to improve the contact tip 25.

[0039] As illustrated in FIG. 6B, the method also includes 104 creating a bore 52 at the distal end 48 of the contact tip 25 along the axis A. Various bore-creating methods may be used, including the use of a drill. As previously noted, the bore 52 has a bore diameter DB that is larger than a channel diameter De of the contact tip 25A. Again, according to embodiments, the bore diameter DB is approximately 1 / 8 of an inch but could have other diameters depending on specific applications.

[0040] As best illustrated in FIG. 4C, the method also includes 106 inserting a length of a metal rod 54 in the bore 52 at the distal end 48 of the contact tip 25. At this point the method also includes 108 fixing the metal rod 54 in the bore 52. According to embodiments, the metal rod 54 has a rod diameter DR that is approximately equal to the diameter of the bore 52 of approximately 1 / 8 of an inch such that the rod 54 may be fixed in the bore 52 via an interference fit which inhibits removal of the rod 54. Other connections may be used, such as an adhesive.

[0041] As best illustrated in FIG. 4D, the method also includes 110 cutting the metal rod 54 to a predetermined length. According to embodiments, the predetermined length substantially matches a length of the bore 52 such that the metal rod 54 terminates at the distal end 48 of the contact tip 25 A. It should be appreciated that this step may alternatively occur prior to insertion of the rod 54 into the bore 52.

[0042] As further shown in FIG. 4D, the method also includes 112 creating a passage 56 through the rod 54 that has approximately the same diameter as the channel 50 of the contact tip 25. Finally, the method includes 114 passing a welding wire 30 through the channel 50 of the contact tip 25 and the passage 56 of the rod 52 such that normal welding operations may be executed with the contact tip 25.

[0043] In accordance with the above, positioning the metal rod 52 at the distal end 48 of the contact tip 25 allows worn material of the contact tip 25 to be replaced with unworn and stronger material of the metal rod 52, thus allowing the contact tip 25 to be re-used and thereby prolonging a usable life of the contact tip 25. Additionally, the method of boring the contact tip 25 and inserting the metal rod 52 may be done quickly in-house, with minimal tools and minimal material usage, thus minimizing downtime of welding operations when fixing / improving the contact tip 25. This leads to overall reductions in manufacturing costs. Additionally, tests of contact tips 25 improved according to the subject method were found tomaintain weld quality as compared to contact tips prior to use of the method. Additionally, the tests revealed a 7% reduction of average current due to the selected material of the rod 54 (a metal composition of refractory metals tungsten, molybdenum and tungsten carbide combined with copper).

[0044] Obviously, many modifications and variations of the present disclosure are possible in light of the above teachings and may be practiced otherwise than as specifically described.

Claims

CLAIMSWhat is claimed is:

1. A method for improving a contact tip for a welding assembly, comprising: providing a contact tip extending along an axis between a proximal end and a distal end and having a channel extending between the proximal and distal ends for receiving a welding wire, the channel having a channel diameter; forming a bore at the distal end of the contact tip along the axis, wherein the bore has a bore diameter being larger than the channel diameter of the channel; cutting a length of a rod, wherein the rod has a diameter that is substantially the same as the bore diameter of the bore of the contact tip; inserting the length of the rod in the bore at the distal end of the contact tip; creating a passage through the rod that has a passage diameter being approximately the same as the channel diameter of the channel of the contact tip; and passing a welding wire through the channel of the contact tip and the passage of the rod.

2. The method as set forth in claim 1, wherein forming the bore includes drilling the bore.

3. The method as set forth in claim 1, further including cutting the rod to a length that is the same as the depth of the bore such that the rod terminates at the end of the contact tip when inserted in the bore.

4. The method as set forth in claim 1, further including securing the rod in the bore of the contact tip.

5. The method as set forth in claim 4, wherein securing the rod includes using an interference fit or an adhesive to secure the rod in the bore.

6. The method as set forth in claim 1, wherein the bore and rod each have a diameter of approximately 1 / 8 of an inch.

7. The method as set forth in claim 1, wherein the rod is of a tungsten, molybdenum, tungsten carbide and copper material.

8. The method as set forth in claim 1, wherein the passage of the rod has a rod diameter, wherein the channel of the body has a body diameter, and wherein the rod diameter and the body diameter are substantially the same.

9. A contact tip for a welding gun, comprising: a body extending along an axis between a proximal end and a distal end; the body defining a channel extending between the proximal and distal ends for receiving a welding wire, the channel having a channel diameter; a bore at the distal end of the contact tip along the axis, the bore having a bore diameter being greater than the channel diameter of the channel; a rod positioned in the bore of the contact tip; and the rod defining a passage extending axially along the axis.

10. The contact tip as set forth in claim 9, further including a welding wire extending through the channel of the body and the passage of the rod.

11. The contact tip as set forth in claim 9, wherein the rod has a length that is substantially the same as a depth of the bore such that the rod terminates at the end of the contact tip when inserted in the bore.

12. The contact tip as set forth in claim 9, wherein the rod is secured in the bore of the body with at least one of an interference fit or an adhesive.

13. The contact tip as set forth in claim 9, wherein the rod has a rod diameter, and wherein the bore diameter of the bore and the rod diameter of the rod are each approximately 1 / 8 of an inch.

14. The contact tip as set forth in claim 9, wherein the rod is of a tungsten, molybdenum, tungsten carbide and copper material.

15. The contact tip as set forth in claim 9, wherein the rod diameter and the channel diameter are substantially the same.

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