1621 results about "Welding defect" patented technology

Laser hybrid welding systems adapted to identify and/or fix a weld defect occurring during a laser hybrid welding process are provided. Embodiments of the laser hybrid welding system may include one or more devices that provide feedback to a controller regarding one or more weld parameters. One embodiment of the laser hybrid welding system includes sensors that are adapted to measure the weld voltage and/or amperage during the welding process and transmit the acquired data to the controller for processing. Another embodiment of the laser hybrid welding system includes a lead camera and a lag camera that film an area directly in front of the weld location and directly behind the weld location.

The invention discloses an electromagnetic current coupling field assisted hybrid melting-brazing method for a laser-TIG arc and equipment. In addition to the use of the welding zone, an alternating magnetic field is added to control properties of plasma formed through ionization of laser, arc and a raw material metal, thereby improving the laser utilization rate. Under the electric field assisted comprehensive effect, the weld melting depth is increased, and the assistant effect on the melting bath of the liquid-state brazing filler metal for laser-arc melting-brazing is realized through electromagnetic stirring and excitation and enhancement, thereby promoting the orderly flow of the liquid-state brazing filler metal and the rupture, wetting, spreading and proliferation of the liquid-state brazing filler metal on the surface of the high metal material, improving the full mixing of the liquid-state brazing filler metal and the base metal formed by melting the low-melting-point metal material, improving the uniformity of the components of the brazed weld, stabilizing the welding process, reducing welding defects, increasing the welding speed, improving the weld formation, optimizing the structure and performance of the brazed weld, and improving the quality of the brazed joint. Moreover, the equipment has the advantages of simple structure, flexible application, low cost, good effect and easy realization.

PCT No. PCT/JP97/01533 Sec. 371 Date Jan. 12, 1998 Sec. 102(e) Date Jan. 12, 1998 PCT Filed May 7, 1997 PCT Pub. No. WO97/43073 PCT Pub. Date Nov. 20, 1997The object of this invention is to prevent the occurrence of welding defects such as undercuts, overlaps and faulty angles of fusion, and to increase the efficiency of welding in the horizontal position. Auxiliary wires 5a and 5b are inserted into molten pool 12, and a unidirectional current is made to flow between them. A magnetic field 9 is induced which is approximately orthogonal to the surface of the parent material so as to generate an upward Lorentz force (opposite the pull of gravity) in molten pool 12. This force supports the molten metal and prevents it from dripping, resulting in a better-shaped bead.

The invention discloses an ultrasonic phased array inspection oil-gas pipe circular weld defect automatic recognition method, in particular to an ultrasonic phased array inspection oil-gas pipe circular weld defect automatic recognition method for a support vector machine, which belongs to a pipe circular weld defect type recognition technology. The recognition method includes two parts of the construction of a support vector machine model and the automatic recognition of unknown defect types in circular weld. The construction steps of the support vector machine model include artificial defect signals extraction, wavelet decomposition promotion, feature extraction, feature optimization and the training of the support vector machine model. The automatic recognition steps of unknown defect types in circular weld include defect signals extraction, optimized feature calculation and automatic recognition based on the support vector machine. The invention combines a lifting wavelet transform with a fractal technology and has the advantages of high recognition accuracy and fast recognition speed. The automatic recognition of the defect types can be realized.

The invention discloses a fill type stirring friction plug repair welding method and a welding tool thereof, and relates to a stirring friction plug repair welding method and a welding tool thereof. The invention adopts fusion welding or friction plug welding for repair welding and causes the welding joints to reduce strength and have poor mechanical performance. The method comprises the followingsteps: (1) the material of a stirring pin is same as that of the part which repairs welding; (2) a conical preset hole is opened; (3) the size of the stirring pin is determined; (4) positioning is carried out; and (5) welding of the stirring friction plug is repaired. The welding tool is characterized in that the side wall of a clamping hole of a lower cylinder is provided with a thread through hole; a stirring body consists of the stirring pin and a stirring pin seat which are combined into a whole from top to bottom; the outer surface of the stirring pin seat is provided with a stirring pinclamping surface; the stirring pin is a cone; the stirring body is arranged in the clamping hole on the lower cylinder; the stirring pin clamping surface aligns to the thread through hole; and the stirring pin is exposed at the outside of the lower end surface of the lower cylinder. The invention is used for repair welding of the weld defects of stirring friction welding and keyholes.

The invention discloses a welding quality analysis device based on infrared vision and an analysis method thereof. The analysis device comprises an infrared vision collecting system that is adjustably and fixedly connected to a welding facility, a vision processing system, in which welding defect intelligent recognition algorithm is embedded, and a feed control system, which can evaluate the welding quality, give an alarm, and adjust the parameters of the welding facility. The analysis method comprises the following steps: (1) collecting the infrared vision information of a molten pool or an area near a molten pool in real time through infrared sensing; (2) processing the infrared vision information by the welding defect intelligent recognition algorithm so as to obtain the weld seam positions and welding defect characteristics; (3) evaluating the welding quality in real time, and controlling the welding facility and giving an alarm aiming at different welding defects. According to the provided intelligent analysis device and intelligent analysis method, the welding process can be monitored in real time, the welding defects can be recognized, the welding seam position can be traced, the welding quality can be evaluated, the welding loss can be reduced, and the finished product yield rate can be increased.

A robot control unit for controlling a tandem arc welding system, which has a welding torch, a robot for weaving the welding torch, a leading electrode power supply, and a trailing electrode power supply, includes a leading electrode detection section and a trailing electrode detection section for detecting quantity of welding state during weaving; a leading electrode processing section for calculating amounts of electrical change; a leading electrode correction section for calculating correction amounts for correcting displacement in horizontal and vertical directions from a weld line of a weaving center trajectory based on the amounts of electrical change; a trailing electrode processing section for calculating an amount of electrical change; and a trailing electrode correction section for calculating a correction amount for correcting displacement in a rotational direction from the weld line of the weaving center trajectory based on the amount of electrical change. According to the robot control unit, arc welding can be performed, which is excellent in accuracy of arc-sensor control, and hardly produces welding defects.

The invention discloses a welding defect extraction method, which belongs to the technical field that a welding technology and a digital image processing technology are crossed. According to the method, an original welding image is dissected by NSST (non-subsampled shearlet transform); for a roughly approximate low-frequency component capable of embodying a defect, the rough region of the detect is extracted by a PCNN (pulse coupled neural network); then, inverse NSST is carried out to the low-frequency component and a high-frequency component subjected to background suppression to obtain a high-frequency characteristic image; after the high-frequency characteristic image is subjected to coarse segmentation, the outline of the defect is optimized by an improved CV (Chan-Vese) model to obtain the fine edge of the defect; and finally extracted results are blended to obtain a finally-extracted defect. The invention also discloses a welding defect detection method adopting the welding defect extraction method. A welding defect structure obtained by the method disclosed by the invention has the advantages of more integral structure and clearer detail and outline, and a more reasonable and accurate reference can be provided for further processing the defect.

An apparatus for monitoring a laser welding bead irradiates a laser to a surface of a welding bead when welding with a laser welding machine, collects a signal reflected from the surface of the welding bead as an image signal, and then extracts at least one feature variable of a bead shape using the collected image signal. Then, the apparatus for monitoring the laser welding bead determines welding defects using the at least one feature variable, and controls an operation of the laser welding machine according to whether or not the welding defects are generated.

A grinding assembly for grinding a weld joint of a workpiece includes a grinder apparatus, a grinder apparatus includes a grinding wheel configured to grind the weld joint, a member configured to receive the grinding wheel, the member being configured to be removably attached to the grinder apparatus, and a sensor assembly configured to detect a contact between the grinding wheel and the workpiece. The grinding assembly also includes a processing circuitry in communication with the grinder apparatus and configured to control operations of the grinder apparatus, the processing circuitry configured to receive weld defect information of the weld joint from an inspection assembly to create a contour grinding profile to grind the weld joint in a predetermined shape based on the received weld defect information, and a manipulator having an end configured to carry the grinder apparatus, the manipulator further configured to operate in multiple dimensions.

The invention relates to a construction steel structure weld ultrasonic phased array detection technology. The technology employs an ultrasonic phased array detection instrument (1) and an ultrasonic phased array probe (2) to detect the weld defect (7) in a weldment's weld (6), and consists of the steps of: 1. instrument setting; 2. instrument calibration; and 3. scanning detection. Specifically the phased array detection instrument comprises a host, the probe, software, a scanning device and accessories. According to the detection technology provided by the invention, ultrasonic phased array is employed to scan the weld only 1 to 2 times so as to finish detection, and the detection result and image are stored. The technology can effectively shorten the detection cycle, can provide beneficial reference basis for ensuring safety assessment of construction steel structure, reduces the occurrence of safety accidents, and provides reference for design to reduce conservative design, enriches construction steel structure weld nondestructive detection methods, improves work efficiency and quality, and escorts construction steel structure welding quality.

The invention discloses a technology for repairing surfacing of a piston rod of a super large marine diesel engine, and the technology can carry out the deep repair of the surface of the piston rod. The adopted surfacing process is as follows: flaw detection and straightening are carried out on the piston rod, turning machining is carried out on the surface of the piston rod to remove a defect layer, and individual deeper cracks are manually removed by grinding; fire whirl is used for heating the piston rod twice, the first heating is carried out till 200 DEG C-250 DEG C, the heating is stopped, the race rotation is carried out for 30 minutes, the second heating is further carried out after the temperature difference between the interior and the exterior is reduced, and a surfacing machine tool is rotated after reaching 250 DEG C-300 DEG C; submerged arc welding is used for rotating dual heads of the surfacing machine tool and a 2Cr13 flux-cored welding wire for carrying out the simultaneous surfacing, and asbestos cloth is used for wrapping and keeping the temperature during the welding process; the piston rod wrapped by the asbestos cloth for slow cooling after the surfacing achieves the size requirement, when the temperature is decreased to be lower than 100 DEG C, the piston rod wrapped by the asbestos cloth is vertically placed till the temperature is decreased to the room temperature, and then the temperature-keeping cloth is removed. The surface of the piston rod after the repair by employing the method has no weld defects, the piston rod fully meets the performance requirements, and the cost is only about one fifth of the cost for fabricating a new piston rod.

The invention discloses a weld seam and weld seam defect detection method based on deep learning. A YOLOV3 network is used to realize weld seam and/or weld seam defect detection. A network training step comprises the following steps of using a positioning frame to select and mark the weld seams in a workpiece image and taking as a training data set; using the positioning frame to select weld defects and mark defect types in a weld seam image, and taking as a training data set I; acquiring coordinates xp and yp of the positioning frame, and width and height sizes wp and hp; initializing a network; randomly acquiring an input tensor aj for training calculation, and outputting a detection result; calculating an error function loss of a prediction result by using the detection result; and adjusting a weight W and an offset value b in combination with a gradient descent method, repeating in the way, and acquiring a trained network. The multiple weld seams and the multiple defect types can be synchronously detected, weld seam identification positioning and defect detection can be realized in one measurement, and measurement efficiency and accuracy are effectively increased.

The invention discloses a constant-speed scanning positioning type post-welding seam tracking and residual stress removal system, which comprises mobile welding equipment, a welding stress removal moving robot, a synchronous motor and two reflection-type distance measuring sensors, wherein the mobile welding equipment is used for welding a welding seam, the welding stress removal moving robot is used for removing welding stress, the synchronous motor is fixedly arranged outside the welding seam and takes the axis of a synchronous motor rotation shaft as a reference point, the two reflection-type distance measuring sensors are fixed on a motor shaft, coaxially rotates with the motor and are arranged at intervals, and reflecting sheets are glued at a welding initial point, a welding nozzle of the mobile welding equipment and the operating tail end of the welding stress removal moving robot. The constant-speed scanning positioning type post-welding seam tracking and residual stress removal system is simple in structure, high in automation and high in post-welding seam tracking precision, and is free from influence of welding slag or welding defect on a post-welding seam.

The invention relates to a method for transient liquid phase diffusion bonding between TiNi shape memory alloy and stainless steel, which belongs to the technical field of the connection of dissimilar materials. In the prior art, the technology of the connection between TiNi shape memory alloy and stainless steel has the problems of welding crack, large crystal grains in the heat affected zone and poor mechanical properties. The transient liquid phase diffusion bonding between TiNi shape memory alloy and stainless steel is realized through the following steps: after the surfaces of TiNi shape memory alloy and stainless steel to be welded and the surface of AgCuTi foil is cleaned and dried, a TiNi shape memory alloy/AgCuTi metallic foil/stainless steel structure is formed, fixed through a welding clip, and then positioned in a vacuum diffusion oven, and welding pressure and temperature are applied to the structure. The method has the advantages that the welding temperature is low (relative to fusion welding), the influence to the base material is small, the connector has no welding defect, the shearing strength of the connector in the room temperature reaches 250 MPa, and the microhardness of the area near the seam section can reach 670 Hv.

The invention relates to a method for welding a heat exchanger tube plate and a welding joint of a heat exchange tube. During assembling of the heat exchange tube and the tube plate, a structure which is sunken into the surface of the tube plate 0.5 to 1 millimeter is adopted; during welding, a welding sequence from bottom to top is adopted, and a 3-shaped or S-shaped welding running line is adopted; during welding, each heat exchange tube is welded with a half of a cycle, and after 8 to 10 heat exchange tubes are welded disposably without arc quenching, the tube plate is subjected to the arc quenching; and according to the same method, the other half of the cycle is welded from bottom to top. Therefore, the frequency of arc stopping and arc starting can be reduced, the welding efficiency is improved, and the number of arc starting and stopping points and the probability of generating welding defects can be reduced. During welding, a tungsten electrode can be stretched into the root part of an included angle between the heat exchange tube and the tube plate easily; during autogenous welding, an electric arc can get to a sharp corner position, and the root part can be penetrated totally without any hollow cavity, so retention of shell side corrosion media is prevented, interval corrosion is avoided and the service life of a welding line is prolonged.

The invention discloses a method for manufacturing a hollow sodium inflating valve with a closed disc end, belongs to a production method of valves of internal combustion engines, and particularly relates to the method for manufacturing the hollow sodium inflating valve with sodium serving as a coolant. According to the method, a pre-workblank with the end shaped like the head of garlic of a bar is formed by the thin and long bar through an electric pier; then, the valve is forged and pressed into the shape of a gas outlet valve workblank through the one-time forging and pressing process in the forging procedure, wherein the valve workblank forming process is in a high temperature state, simple in process route, low in manufacturing cost and high in efficiency. An inner hole of the valve is machined through a deep hole gun-drill, and therefore the diameter of the inner hole, the depth of the inner hole, the roughness of the inner hole, the coaxiality of the inner hole and the evenness of the wall thickness can be ensured, the machining rhythm is quick, efficiency is high, and cost is low. By means of the method of utilizing steps at the welding point of a disc end face sealing cover and the valve, welding defects are reduced, and welding strength is high.

The invention discloses a pressure vessel weld defect identification method and device based on a neural network. A computer reads in a radiographic inspection negative film image, and whether the quality of the negative film image is qualified or not is determined according to the read-in average darkness value of the negative film image; the negative film image is enhanced according to a fuzzy theory, and de-noising processing is conducted on the enhanced negative film image according to median filtering; a weld joint region is separated from the negative film image obtained after de-noising processing is conducted according to the morphological feature, and an original weld joint gray value is retained; defect filtering is conducted on the separated negative film image according to a mean filter, and a simulated ideal weld joint is formed to serve as a virtual background, the virtual background is subtracted from the original weld joint, and the weld joint defect is obtained after enhancement and de-noising are conducted. The invention further discloses the pressure vessel weld defect identification device, radiographic inspection weld joint images can be identified effectively, identification accuracy reaches 92%, the detection cost can be reduced greatly, and efficiency is improved.

The invention discloses an online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on a characteristic element plasma optical signal, comprising the following steps: welding the galvanized steel with a focused laser beam; simultaneously, adding copper powder at a welding part in the welding process; acquiring the characteristic element plasma optical signal in the laser powder-adding welding process of the galvanized steel by a photosensitive sensor; implementing online monitoring on types of the characteristic elements of the plasma generated by ionization of materials in the welding process and additive amount m of corresponding characteristic elements according to variation of the characteristic element plasma optical signal; and finally, obtaining relation between the characteristic element plasma optical signal and the welding defects. In the method, properties of the characteristic elements to the plasma optical signals are analyzed so as to judge whether the welding defects are generated and the generation time on line in real time, and the method can be used for online monitoring of defects in the laser welding process in practical production, and laying the foundation for online quality control of following laser welding processes.

The invention discloses a limited welding seam manufacturing method for an oblique Y-shaped groove crack welding test. The method comprises the following steps that (1) groove machining: mechanical premachining is performed on a groove of a to-be-welded test piece; (2) weldment assembling: a gap d is reserved on a limited welding seam position, the d and the weldment thickness t satisfy the relation: d=4.32-1.92*exp(-0.0383*t), 9<=t<=100 mm; (3) welding: the welding currents of a backing weld range from 100 A to 150 A, when filling and cosmetic welding are performed, in order to prevent angular deformation, the front face and the back face are alternately welded until the welding is completed, the welding currents of a first weld pass to a sixth weld pass range from 120 A to 170 A, a welding gun does not swing, the welding currents of subsequent weld passes range from 120 A to 250 A, the welding gun can swing, and the width of the weld passes is controlled within 20 mm. The limited welding seam manufactured by the method has no weld defect, the weldment gap can be guaranteed without needing to insert a patch into the welding test position, the heavy work of dismantling the patch is left out, the labor intensity is reduced, and the working efficiency is improved.

The invention discloses a weld defect characteristic parameter extraction method. The method comprises steps as follows: a weld joint image is acquired; the weld joint image is preprocessed; the weld joint image is subjected to binarization segmentation; the background of the weld joint image is removed; a weld defect is marked; geometrical characteristic parameters of the weld defect are extracted. According to the weld defect characteristic parameter extraction method, early preparations are made for classification and recognition of the weld defect by acquiring the perimeter, the area, the circularity and other geometrical characteristic parameters of the weld defect, main characteristic information of the weld joint is reserved, reliable guarantee is provided for recognition of the weld defect, the dimensionality of characteristic data of the weld defect is reduced, and the recognition speed of the weld defect is increased.

The invention relates to a laser filler wire welding method for a thick plate narrow gap, and belongs to the technical field of laser material processing. The laser filler wire welding method for the thick plate narrow gap is characterized by comprising the steps that positive out-of-focus laser beams are adopted, the laser beams enter a narrow gap groove of a workpiece to be welded and act on the bottom and the side wall of the groove, and a welding pool is formed in a thermal conducting welding mode; a filler wire enters the welding pool in a wire forward feeding mode and is heated through the welding pool to be molten, the gap is filled with the molten wire to form a weld joint, and a thick plate is connected in a single-path multi-layer welding mode. According to the laser filler wire welding method for the thick plate narrow gap, the thermal conducting welding mode and the mode that the filler wire is heated through the welding pool to be molten are adopted, and the welding process is stable; meanwhile, the laser beams act on the side wall of the groove so that the welding defects such as the defect that the side wall is incompletely fused can be effectively avoided.