78 results about "Gas tungsten arc welding" patented technology

Friction stir welding is enhanced by preheating of the workpiece with an electrical arc, such as an arc applied by a common gas-tungsten arc welding (GTAW) torch. As the arc is moved about a path on the workpiece, it preheats or partially welds the path, with the friction stir welding head following along the path to complete the weld.

The invention provides a method for detecting the stability of the gas tungsten arc welding (GTAW) additive manufacturing process based on arc voltage feedback. The method comprises the steps that the stability of the process is reflected through the arc length, the arc length is indirectly fed back though arc voltage, and the initial position of a GTAW gun on a substrate is adjusted; in the forming process of a first layer, a voltage sensor is matched with a data acquisition card to obtain a variation signal of the arc voltage along a forming path; the arc voltage is converted into the arc length according to a calibration relationship, a variation signal of the arc length along a forming path is obtained, and a second layer, a third layer until the n layer are formed, so that a variation signal of the n layer arc length along a forming path is obtained; and if the arc length is within a certain range, it is judged that the forming process is stable. According to the method for detecting the stability of the GTAW additive manufacturing process based on arc voltage feedback, the purpose of real-time detection of the stability of the GTAW additive manufacturing process is effectively achieved, and the detection process is easy to operate, high in stability, not prone to being interfered by intense arc light, high in calculation speed, capable of achieving automation easily and suitable for engineering application of real-time site detection.

System for repairing worn surfaces of steam turbine components and especially high pressure turbine rotors, are disclosed. These systems include depositing a first layer of weld metal on a worn surface of the component, whereby a heat-affected zone is created. A second layer of weld metal is then deposited over the first layer using a greater amount of heat to temper at least a portion of the heat-affected zone produced by the first layer. The preferred embodiments include the use of gas tungsten arc welding for providing fine-grain size and more creep resistance, especially in the weld and heat-affected zone. The resulting build-up can be machined, for example into a blade fastening to produce a component having properties equal to or better than the base-metal alloy. The invention also provides a longer lasting turbine system, including rotors which have serrated steeples that are more resistant to failure.

The invention discloses a gas tungsten arc welding (GTAW) system and a welding method thereof. The GTAW system comprises a first welding machine, a second welding machine, a wire conveying device, a first welding torch and a second welding torch, wherein the negative electrode of the first welding machine and the negative electrode of the second welding machine are connected with the first welding torch; the positive electrode of the first welding machine is connected with a workpiece; the positive electrode of the second welding machine is connected with the second welding torch; the first welding machine and the first welding torch form a main loop, so that a main loop arc is formed between the first welding torch and the workpiece; and the second welding machine, the wire conveying device and the second welding torch form a bypass loop, so that a bypass arc is formed between the second welding torch and the first welding torch. According to the method, the resistance heat of a welding wire is fully used for preheating the welding wire, and an arc heating fuse is used, so that the melting efficiency of the welding wire is improved further; due to the arc between a filling wire and a tungsten electrode and a self-adjusting function of the arc, the feeding speed of the welding wire is flexible, so that a wire clamping phenomenon is avoided, and the welding process is relatively stable; and the system and the method are suitable for various metal filling wires.

A method of preparing a mechanical component with an Fe—Cr—C hardfacing weld overlay alloy for improving the resistance of the mechanical component to abrasion, erosion or erosion/corrosion for use in very abrasive, erosion or erosive/corrosive environments by significantly increasing the hardness of the weld overlay is disclosed. To improve the resistance to abrasion, erosion or corrosion, a weld overlay of a Fe—Cr—C hardfacing alloy is applied onto the surface of a metallic component, such as tubes, pipes, or vessels. Welding and cladding methods including gas-metal-arc welding (GMAW), gas-tungsten-arc welding (GTAW), and laser cladding may be utilized. Then, the component is heat-treated at elevated temperatures for a sufficient time, resulting in additional hardening and thus further increasing the weld overlay's resistance to abrasion, erosion, or erosion/corrosion.

The present invention discloses method for joining titanium and stainless steel using Gas Tungsten Arc welding with V butt joint welding type. Intermediate bi-filler rods of vanadium and aluminum bronze are introduced to the weld pool between the titanium and the stainless steel, as the arc welding current is applied thereof The vanadium filler rod is placed adjacent to the titanium and the aluminum bronze filler rod is placed adjacent to the stainless steel, and the two intermediates filler rods are placed adjacent to each other. The present invention also discloses method for joining titanium and carbon steel by means of Gas Tungsten Arc welding with V butt joint welding type.

The present invention relates to a manufacturing method for advanced high-strength steel (AHSS) wheel, comprising the following steps. Take an AHSS with at least 590 MPa of tensile strength for rolling to circular ring of a rim. Apply low heat input welding, such as the cold metal transfer (CMT) welding or the gas tungsten arc welding/tungsten inert gas arc welding (GTAW/TIG), at the junction of the rim to form a hollow cylindrical rim. Then perform hole expanding and spinning/roll forming operations to the rim. Take another AHSS with at least 980 MPa of tensile strength for pressing and forming a disk. Apply low heat input welding, such as cold metal transfer (CMT) welding, to the rim and the disk to produce a wheel. According to the present invention, the welding quality of products can be improved significantly; the fatigue lifetime of wheels can be enhanced; and wheels are lightweight.

Gas metal arc welding (GMAW) is a widely used process for joining metals. Its main advantage over its competition gas tungsten arc welding (GTAW) is its high productivity in depositing metals. However, to melt metal from the wire to deposit into the work-piece, additional heat is consumed and applied to the work-piece with an uncontrolled fixed proportion to the effective heat that melts the wire. Such additional heat is often in excess of the needed heat input for the work-piece. The side-effects include a waste of the energy, an increased distortion, and possible materials property degradation. This invention is to device a method to transfer this part of heat to melt the wire by adding two wires, which form a pair of arc spots, under a tungsten arc. It also devices a method to assure the arc between the two wires be maintained stable such that the transfer be successfully continuous. The successful continuous transfer improves the energy efficiency, eliminates the adverse effects on the distortion and materials property, and decouples the controls on mass input and heat input on the work-piece.

A speedy method of welding in a tight space using a single pass is provided using a technique which involves the use of a particularly shaped, flux treated consumable insert to provide deep weld penetration by a GTAW machine which is compact and fits the narrow spaces found in applications such as feeder tube repair since it does not require an insert wire flux feed system and is thus capable of negotiating narrow spaces found in feeder tubes.

The invention relates to a manual dual phase steel SA-240 S31803 gas tungsten arc welding (GTAW) technology which is characterized by comprising the following steps: a 30 degree plus 5 degree divided edge is formed on a welding surface by a mechanical method, water, oil stain, iron rust and welding wires on the surface and both sides of the divided edge are gotten rid of, a contravariant AC tungsten electrode argon arc welding machine is used as a welder, (Ar plus (1 to 2 percent) N 2) mixed gas is the protective gas in a welding torch, pure argon is used as back protective gas, the diameter of the selected solid ER2209 welding wire is 2.4mm, the diameter of the welding nozzle of the contravariant AC tungsten electrode argon arc welding machine is 12 mm, the diameter of a tungsten bar is 2.4mm, and the purity quotient of argon is 99.995 percent. The welding technology includes the bottoming of the bottom of the divided edge and the welding of the surface of an upper filling cover, the welding operation is the straight channel welding, and the welding of the surface of the upper filling cover comprises the welding of left and right crossed straight channels. The heat input ranges from 0.5 to 2.5 KJ/mm during welding, the interlayer-temperature does not exceed 150 DEG C, and the thickness of each layer welding seam does not exceed 2.5mm. The welding technology has the advantages that the content of ferrolites in each welding seam can be guaranteed to range from 35 to 60 percent, and the resistance to corrosion and chemical components of the dual phase steel can not be destroyed.

A bearing surface of an oilfield component is treated by applying a surface treatment having a low coefficient of friction to the bearing surface of the oilfield component by weld fusing an overlay of a Cu—Ni—Sn alloy material to the bearing surface. Weld fusing the overlay of the Cu—Ni—Sn alloy material to the bearing surface can involve laser surface cladding the overlay of the Cu—Ni—Sn alloy material to the bearing surface, gas tungsten arc welding the overlay of the Cu—Ni—Sn alloy material to the bearing surface, or plasma tungsten arc welding the overlay of the Cu—Ni—Sn alloy material to the bearing surface.

An austenitic steel welded joint is produced by gas tungsten arc welding an austenitic steel base metal with a welding material of austenitic steel having a composition comprising: C≦0.1%; Si≦0.8%; Mn: 1.5 to 5.5%; Ni: 8 to 15%; Cr: 18 to 24%; Al<0.05%; N: 0.15 to 0.35%; and one or more of V≦0.5%, Nb≦0.5%, and Mo≦4.5% if necessary, the balance being Fe and impurities that contain O≦0.02%, P≦0.05%, and S≦0.03%. The chemical composition satisfies [413−462(C+N)−9.2Si−8.1 Mn−13.7Cr−9.5Ni−18.5Mo≦−70]. The amount of ferrite of the weld metal is 20% or less in area ratio. The welded joint has high strength and excellent hydrogen embrittlement resistance and is useful in high-pressure hydrogen gas piping where no postweld heat treatment is performed.

A welding system may include a welding power source that provides power for both a gas metal arc welding (GMAW) process and a gas tungsten arc welding (GTAW) process. Further, the welding system may include a wire feeder coupled to the welding power source for providing wire, gas flow, and electrical current flow for the GMAW process. Additionally, the welding system may include an adapter that couples to the wire feeder to provide the electrical current flow and the gas flow for the GTAW process.

A laser cladding or plasma transferred arc overlay welding process may be used advantageously to apply and to control the material properties of a coating designed for protecting the substrate against wear, corrosion and oxidation at elevated temperature. Furthermore, a laser cladding or plasma transferred arc overlay welding process may be used to apply the coating alloy materials in applications where traditional thermal spray or weld-applied coatings are not practical. By using these welding methods very good bonding is achieved by fusion during welding. At the same time the properties of the clad layer is preserved by the limited dilution typical of these two welding methods compared traditional overlay welding, by e.g. Gas Tungsten Arc Welding and the like.

The invention discloses a flux-cored wire for welding of 2Al2 high-strength aluminum alloy tungsten inert gas arc welding, and belongs to the technical field of aluminum alloy welding. The filling rate of the flux-cored wire is 20 % to 30 % with a 1070 semi-hard pure aluminum strip as the outer skin, wherein powder comprises the alloy components in percentage by mass: 22 % to 29 % of Cu powder, 0.5 % to 25 % of micro-nano ceramic powder, 2 % to 4.5 % of Mn powder, 1 % to 2.5 % of V powder, 1 % to 2 % of AlTi alloy powder, 1.5 % to 5 % of Zr powder, 1 % to 6 % of rare earth metal powder, and the balance of pure aluminum powder. The welding is well formed, defects such as bulge and undercut are avoided, and all properties of weld metal meet the engineering requirements.

In gas tungsten arc welding (GTAW), the achievable deposition rate of the filler wire is coupled with the arc energy and the mass of the molten metal in the weld pool. In this invention, a side arc is added into the GTA (gas tungsten arc) between the wire and the same tungsten that establishes the GTA with the work-piece. While its anode provides a GMAW (gas metal arc welding) melting mechanism to completely melt the wire at high speeds, the undesirable dependence of deposition rate on the weld pool mass is also eliminated. As a result, the deposition rate is increased and the ability to provide desirable deposition rate and base metal melting/penetration freely without coupling is established for the GTAW.