HOT-WIRE CONSUMABLE WITH EMBEDDED ID TAG

A system and method for using filler wire with embedded information is provided. The filler wire includes a sheath comprising a first filler material and a core that is defined by the sheath. The core includes a second filler material and at least one integrated circuit module. The at least one integrated circuit module includes at least information about the filler wire. In some embodiments, the at least one integrated circuit module is configured for at least one of read operations and write operations that are done using a remote device.

DETAILED DESCRIPTION

Exemplary embodiments of the invention will now be described below by reference to the attached Figures. The described exemplary embodiments are intended to assist in the understanding of the invention, and are not intended to limit the scope of the invention in any way. Although much of the following discussions will reference “welding” operations and systems, embodiments of the present invention are not just limited to joining operations, but can similarly be used for cladding, brazing, overlaying, etc.—type operations. Like reference numerals refer to like elements throughout.

As indicated above, it would be desirable to embed information concerning the weld creation into the weld for later retrieval. Because welding/joining operations typically involve a filler metal that is combined with at least some of the workpiece metal to form the weld joint, it would desirable to embed the information in the filler material, e.g., as a component of the filler material. In this way, some or all of the records for weld creation can stay with the weld, rather than having to be filed in a remote location. However, because traditional methods can use an arc to transfer the filler material, any materials containing this information may get consumed, damaged or altered in the arc, rather than being deposited intact in the weld puddle. According, unlike most welding processes, the present invention does not use an arc to heat, melt and transfer the filler materials to the weld joint or cladding layer. As described below, exemplary embodiments of the present invention can deposit information containing materials into the weld joint, which provides significant advantages over existing welding technologies.

FIG. 1illustrates a functional schematic block diagram of an exemplary embodiment of a combination filler wire feeder and energy source system100for performing any of brazing, cladding, building up, filling, hard-facing overlaying, and joining/welding applications. The system100includes a high energy heat source120/130capable of heating the workpiece115to form a weld puddle145. The high energy heat source can be a laser subsystem130/120that includes a laser device120and a laser power supply130operatively connected to each other. The laser120is capable of focusing a laser beam110onto the workpiece115and the power supply130provides the power to operate the laser device120. The laser subsystem130/120can be any type of high energy laser source, including but not limited to carbon dioxide, Nd:YAG, Yb-disk, YB-fiber, fiber delivered, or direct diode laser systems. Further, even white light or quartz laser type systems can be used if they have sufficient energy. For example, a high intensity energy source can provide at least 500 W/cm2.

The following specification will repeatedly refer to the laser subsystem130/120, beam110and laser power supply130, however, it should be understood that this reference is exemplary as any high intensity energy source may be used. For example, other embodiments of the high energy heat source may include at least one of an electron beam, a plasma arc welding subsystem, a gas tungsten arc welding subsystem, a gas metal arc welding subsystem, a flux cored arc welding subsystem, and a submerged arc welding subsystem.

It should be noted that the high intensity energy sources, such as the laser device120discussed herein, should be of a type having sufficient power to provide the necessary energy density for the desired welding operation. That is, the laser device120should have a capability to modify the energy from the laser power supply (or other source) to create and maintain a stable weld puddle throughout the welding process, and also reach the desired weld penetration. For example, for some applications, lasers should have the ability to “keyhole” into the workpieces being welded. This means that the laser should have sufficient power density to penetrate (partially or fully) into the workpiece, while maintaining that level of penetration as the laser travels along the workpiece. Exemplary lasers should have power capabilities in the range of 1 to 20 kW, and may have a power capability in the range of 5 to 20 kW. In other exemplary embodiments, the power density can be in the range of 105to 108watts/cm2. Higher power lasers can be utilized, but can become very costly.

The system100also includes a hot filler wire feeder subsystem capable of providing at least one filler wire140to make contact with the workpiece115in the vicinity of the laser beam110. Of course, it is understood that by reference to the workpiece115herein, the molten puddle, i.e., weld puddle145, is considered part of the workpiece115, thus reference to contact with the workpiece115includes contact with the puddle145. The hot filler wire feeder subsystem includes a filler wire feeder150, a contact tube160, and a hot wire power supply170. In accordance with an embodiment of the present invention, the hot wire welding power supply170is a direct current (DC) power supply (that can be pulsed, for example), although alternating current (AC) or other types of power supplies are possible as well. The wire140is fed from the filler wire feeder150through the contact tube160toward the workpiece115and extends beyond the tube160. During operation, the extension portion of the filler wire140is resistance-heated by an electrical current from the hot wire welding power supply170, which is operatively connected between the contact tube160and the workpiece115. Prior to its entry into the weld puddle145on the workpiece115, the extension portion of the wire140may be resistance-heated such that the extension portion approaches or reaches the melting point before contacting the weld puddle145on the workpiece115. Because the filler wire140is heated to at or near its melting point, its presence in the weld puddle145will not appreciably cool or solidify the puddle145and the wire140is quickly consumed into the weld puddle145. The laser beam110(or other energy source) serves to melt some of the base metal of the workpiece115to form the weld puddle145and complete the melting of the wire140onto the workpiece115. However, the power supply170provides the energy needed to resistance-heat the filler wire140to or near a molten temperature.

The system100also includes sensing and control unit195. The sensing and control unit195can be operatively connected to the power supply170, the wire feeder150, the laser power supply130, and/or ID tag control unit180(discussed further below) to control the welding process in system100. U.S. patent application Ser. No. 13/212,025, titled “Method And System To Start And Use Combination Filler Wire Feed And High Intensity Energy Source For Welding” is incorporated by reference in its entirety and provides exemplary methods and systems of operating the system100.

As indicated above, the present invention melts the filler wire140into the weld puddle145rather than using a welding arc to heat, melt and transfer the filler wire140into the weld puddle145. Because no arc is used to transfer of the filler wire140in the process described herein, the filler wire can include materials that normally would be consumed in, interact with, or damaged by the arc in such a manner as to not exist or be rendered inoperable in the puddle following solidification. For example, materials such as integrated circuits can be transferred in the filler materials. These integrated circuits, referred herein as “ID tags,” can be configured to include information related to weld creation as discussed above, and can be deposited into the weld or cladding via tag modules142, which will be discussed further below. “ID tag” as used herein is intended to include any type of integrated circuit, RFID device, or any other type of device that can store data which can be interrogated at a later time to retrieve the data.

In an exemplary embodiment, as illustrated inFIGS. 2A and 2B, the filler wire140is composed of a sheath141and a core143. The sheath141can be made of any filler material that is appropriate for the process, weld, cladding, etc. Further, the core143can be made up of a number of different compositions depending in the desired process parameters. For example, the core can be a solid material, can be a flux material, can be metallic powder, etc., without departing from the spirit or scope of the present invention. Thus, the core143can be made of a solid material which can have a composition which is similar to, or different from, the sheath141. Alternatively, the core143can be made of a flux, powder, etc. as needed for the process. As shown, the tag modules142are embedded in the core143of the wire140so that they can be delivered to the puddle145during the process. In exemplary embodiments, the tag modules142can be comprised of an ID tag142′ and a tag coating144. The tag coating144can be any type of material which is capable of protecting the ID tag142′ from the molten puddle145or the process so that it retains its integrity. Such materials can include, but are not limited to nickel, ceramic, etc. In yet a further embodiment, the wire140can be solid with tag modules142embedded therein.

The size of the tag modules142are such that they can be deposited into the puddle145and not adversely interfere with the completed joint, surface etc. For example, the tag modules can have a maximum outer diameter size in the range of 0.7 mm to 1.5 mm to allow them to fit into a consumable. The length of tag module is not so limited. Of course, the utilized size must take into account the resultant utilization of the wire140and the geometry of the weld bead, cladding layer, etc. Furthermore, embodiments of the present invention are not limited to the outer shaping of the coating144. Thus, in some embodiments the tag module142can have a spherical, elliptical or oval shape. However, it should be noted that is some applications the tag module142is to have a shape that avoids the use of sharp corners which can cause stress concentrations in a resultant weld bead or joint.

In some embodiments of the invention, the ID tags142are distributed in the wire140at periodic distances L. For example, one or more tag modules142may be deposited into the wire140every 6 to 36 inches. Of course, the modules142may be distributed at any desired frequency or even randomly as long as the application requirements are met and the inclusion of the modules142does not substantially affect the integrity of the weld, coating, etc.

In exemplary embodiments, the ID tags142′ include information that relates to the consumable such as the type of wire, manufacturer, lot or production no., date of production, etc. Any other desired information can be stored on the tags142′. The ID tags142′ may also be configured to include information concerning the weld creation such as the operator ID, the date/time of the weld, the welding process (e.g., GMAW, GTAW, PAW, etc.), the temperature of the weld puddle, weld cooling rate, etc. In some embodiments, the ID tags142′ are passive in that they do not transmit the information until scanned by a reading device. In other embodiments, the ID tags142′ are active and transmit the information, e.g., periodically such as once every minute. The ID tags142′ may also include sensors that, for example, monitor the temperature of the weld, etc. In some exemplary embodiments of the present invention, the retrieval of information from the ID tags142′ includes nondestructive methods such as wired or wireless communications. In some exemplary embodiments, the ID tags142′ are radio frequency ID (“RFID”) tags. The construction of ID tags such as RFID tags are well known in the art and will not be further discussed.

When configuring the welding system to use wire140with ID tags142′, the temperature rating of the ID tags142′ may be important. This is because, depending on the welding operation, type of materials being welded, type of consumable wire140, etc., the temperature of wire140after contact tube160and/or the weld puddle145may be above the rated temperature of ID tag142′ for read/write operations to function. That is, devices will not be able to read from or write to the ID tags142′ until the temperature of the ID tags142′ drops below the rated temperature. Accordingly, in such cases, any read/write operation must occur prior to the ID tag's insertion in to weld puddle145and after the weld cools sufficiently. For example, the welding system100can be configured to write the desired information into ID tags142′ immediately prior to their insertion into weld puddle145and read it at a point downstream of welding operations after the weld has cooled to below the rated temperature of the ID tags142′.

As illustrated inFIG. 1, an ID tag control unit180can be operatively connected to ID tag writer185and ID tag reader186to respectively write information to or read information from ID tags142′ in the modules142. Of course, the read/write functions may be incorporated into a singe device if desired. The ID tag writer185can transmit (i.e., write) weld creation information such as date/time of weld, operator ID, type of welding process, type of filler wire, manufacturer of filer wire, etc. to ID tag142′. If the temperature of the weld puddle145will be above the rated temperature of the ID tags142′, the welding system100can be set up such that ID tag writer185writes the desired information prior to the ID tag142′ being inserted in the weld puddle145. Of course, the ID tag142′ may be pre-configured with some of the desired information such as type of wire and manufacturer at the time the wire140was manufactured or shipped. An ID tag reader186may be used to read the information from ID tag142′. For example, ID tag control unit180may verify that the weld information was correctly written by ID tag writer185by reading the information from the ID tags142′ at a point downstream of the welding operation. Once written, the information in ID tags142′ may be retrieved at any time. For example, inspection personnel can use portable readers (not shown) to access the information written to the ID tags142′ at any time, even years later. In some embodiments, the ID tags142′ include a sensor (not shown) that can measure and store parameters such as the maximum temperature and the cool down rate—to name just a few parameters.

In some cases, the temperature of wire140and/or weld puddle145may be high enough to damage the ID tags142′. For example, the heat of an arc can be as high as 8,000° F., and the melting temperature of the filler wire140, which will vary depending on the size and chemistry of the wire140, can exceed 1,500° F. In such cases, the ID tags142′ may need to be protected from the heat of the wire140and/or weld puddle145. This was explained briefly above with respect to the coating144.

FIGS. 3A to 3Cdepict exemplary embodiment of modules142within the scope of the present invention. As shown inFIG. 3A, which depicts a similar module toFIG. 2A, the module142is constructed such that a coating144surrounds the ID tag142′. In some embodiments, the coating144is an insulating coating which protects the tag142′ from any high heat exposure. For example, the coating144can be a ceramic coating. That is, the coating144can be any composition that resists the transfer of heat such that the puddle145cools and solidifies before the tag142′ is destroyed by the heat. In the embodiment shown, there is a single coating144, but other exemplary embodiments are not limited to this, as the coating144can be made up of a plurality of different layers having different thermal protective properties to optimize protection of the tag142′. In other embodiments (FIG. 3B), the outer portions of the coating144may be designed to melt and/or ablate in order to protect the tag142′. In such cases, the coating144may interact with the molten components in the puddle145(filler wire and/or workpiece). In such embodiments, the coating144melts away from the module142in an effort to absorb and/or dissipate heat from the tag142′. In such embodiments, the coating can be a nickel or other metallic material that will melt, but still provide thermal protection to the tag142′. In still other embodiments (FIG. 3C), the tag142′ is protected by plurality of layers having different thermal properties, such as melting temperatures. For example, the module can have a first coating layer144″ that insulates and a second coating layer144′ that melts and/or ablates. For example, the first layer144″ can be made from a ceramic material, while the second layer144′ is made from a metal that will at least partially melt in the puddle145. In the above embodiments, the type and thickness of the coatings144,144′ and/or144″ can depend on the process being utilized, the temperature rating of the ID tag142′, the maximum temperatures of the weld puddle145, the wire140, and the expected cooling rate of puddle145. Various manufacturing methods can be used to coat the particles, including using vapor deposition, or other similar coating methods.

As discussed above, the temperature of the wire140and/or the puddle145can be an important operational parameter depending on the temperature rating of the ID tag142′ being deposited. In addition, it may be desirable for the ID tag142′ to include the temperature of the filler wire140and/or the puddle145for future reference. Accordingly, in yet another exemplary embodiment of the present invention, the system100can include thermal sensors (not shown) that monitor the temperature of filler wire140and of puddle145. The temperature can then be used to control the heating of wire140and of the puddle145by laser beam110to ensure the ID tags142′ are not damaged while maintaining weld quality. For example, as each module142is to enter the puddle the system100can be controlled such that the heat input is temporarily reduced by either reducing or turning off the laser briefly. Alternatively, or additionally, any heating methodology used to heat the wire140(such as resistance heating) can be reduced at the point that a module142is to enter the puddle145. These, and other temperature measurements, can be written to ID tags142′ by ID tag control unit180. U.S. patent application Ser. No. 13/212,025, titled “Method And System To Start And Use Combination Filler Wire Feed And High Intensity Energy Source For Welding” is incorporated by reference in its entirety, provides exemplary embodiments on how sensors can be incorporated into sensing and control unit195for operating system100.

Of course, the ID tags142′ and the filler material need not be included in the same wire or consumable. Because, in some embodiments, an arc is not used to transfer the filler wire to the puddle145, the feeder subsystem can be configured to simultaneously provide more than one wire to the puddle at the same time, in accordance with certain other embodiments of the present invention. For example, in some exemplary multi-wire embodiments one of the wires (for example the leading wire) can deposit the matrix of the weld joint while any additional wires adds the ID tags142′ as described herein. That is, as shown inFIG. 4, a first wire140A may be used to add structure to the workpiece and a second wire140B may be used for depositing the modules142to the workpiece115. In this way, a standard filler wire140A can be used for most welding operations and filler wire140B is only fed into the puddle145when weld information needs to be inserted. Because the filler wire140B is designed for depositing the modules142, any heating (if needed) of filler wire140B can be done independently of wire140A to ensure that the wire140B in under the rated temperature of ID tags142′. Accordingly, in some embodiments, the second wire140B is not heated or is heated to a temperature that is below the temperature rating of ID tags142′ in order to minimize the risk of heat damage to the tags142′. The second wire140B can then inserted into a trailing edge of puddle145such that the second wire140B will fully melt but will also quickly solidify and cool the puddle145. In this way, the amount of heat seen by the ID tag142′ is minimized. In some embodiments, the wire feed speed of the second wire140B is different from the first wire140A. In some embodiments, the wire feed speed of the second wire140B is less than that of the first wire140A such that the ID tags142′ can be closely spaced in second wire140B to, for example, minimize manufacturing costs. In other embodiments, the wire feed speed of the second wire140B is more than that of the first wire140A or the same as the first wire140A.

The density of the material used for the coatings144of the ID tags142′ may vary depending on the application and whether it is desirable to have the ID tag142′ near the top of the weld joint or at the bottom. For example, in some embodiments, devices may not be able to read from or write to the ID tags142′ if they are deposited too deep in the weld. In such cases, it may be desirable to have a module142that is less dense than the surrounding filler material so that the module142goes to the top of the weld joint as it cools. In other application such as, for example, out-of-position welding, it may be desirable to have a module142that is denser than the surrounding filler material. Of course, in some cases it may be desirable for modules142to have the same density as the surrounding filler material. To achieve the desired density the density of the coating144can be utilized to achieve the desired density for the entire module142. It is noted that although the above embodiments show a typical weld joint, embodiments of the present invention are not limited in this regard as the wires can also be used for cladding/surfacing operations, and can be used in other weld joint types. These figures are intended to be exemplary.

In other exemplary embodiments, similar toFIG. 4, the modules142are deposited onto or into the puddle145via a methodology not including the utilization of a wire140B as a delivery system. For example, some exemplary embodiments the modules142can be dropped onto the puddle145as the operation is processing from a device that places the modules in the appropriate position of the weld puddle before the puddle solidifies. This can be done in operations where it is not desirable to have the modules142completely submerged within the puddle145, but rather embedded on a surface thereof. For example, as shown inFIG. 5, embodiments of the present invention, can use a placement mechanism (not shown) to place the modules142on a surface of the weld or cladding bead501such that at least some of the modules142is exposed. In such embodiments, the modules142can be deposited downstream of the joining/cladding operation but prior to the bead501solidifying such that the modules are at least partially embedded and secured into the bead501, but they are at least somewhat exposed to allow reading and recording of data to be easier. Further, such embodiments could minimize compromising the structural integrity of the bead501or weld joint by completely submerging the modules within the bead501. Further, such embodiments can allow the placement of the modules142to easily vary during the operation such that the modules can be placed as desired. For example, rather than placing the modules142every fixed distance (corresponding to distance L in the wire140) the modules can be placed at the beginning and end of an operation, and at various points in between an operation. Further, placement can be achieved at locations which are not structurally critical.

InFIG. 1, the laser power supply130, hot wire power supply170, wire feeder150, ID tag control unit180, and sensing and control unit195are shown separately for clarity. However, in embodiments of the invention these components can be made integral into a single welding system. Aspects of the present invention do not require the individually discussed components above to be maintained as separately physical units or stand alone structures.