Semiadaptive Synergic-Fill Welding Tractor for Ship Unit Erection

2003 ◽  
Vol 19 (03) ◽  
pp. 151-158
Author(s):  
D. Harwig ◽  
B. Zheng ◽  
C. Reichert ◽  
T. Huang ◽  
A. Joseph ◽  
...  
Keyword(s):  
Control Algorithm ◽  
Weld Bead ◽  
Seam Tracking ◽  
Welding Parameters ◽  
Bead Size ◽  
Welding Torch ◽  
Starting Point ◽  
Flux Cored Arc Welding ◽  
Joint Width ◽  
Weld Bead Size

At most U.S. shipyards, the bottleneck for improving productivity is unit fabrication and ship erection. Fit-up during unit, super-unit, and ship erection is difficult, resulting in variable gap and mismatch, which promote defects and repair. A semiadaptive synergic-fill welding tractor was developed for improving the productivity of seam welds during erection. The tractor has many features that advanced robots have but is simple to use because it relies on operator pass planning instead of robotic path preplanning. The "synergic-fill" welding concept was developed to maximize the deployment of robust welding procedures. This was a new control process for making changes to weld bead size during fabrication using one knob. The synergic-fill welding concept was developed for flux-cored arc welding of DH36 steels for horizontal erection seams. These seams have a range of gap and require a range of weld bead sizes to uniformly fill the weld seam. Welding parameters that ensured a constant base metal dilution were optimized and programmed into the synergic control. In addition, the welding tractor was developed with a laser seam tracking vision sensor and adaptive-fill control. The new control allows the operator to intervene during welding and toggle the adaptive features on and off. A special four-axis tractor was developed to permit cross-seam and torch height control for seam tracking while oscillating the welding torch. The laser sensor was integrated with modular fixturing to permit welding with either angled or transverse oscillation. The adaptive control algorithm varied the weld size from the synergic-fill starting point that was selected by the operator. The weld bead was made proportionally larger or smaller as the joint width became larger or smaller within the process capability range. A semiadaptive control algorithm was developed for the horizontal welding application. The process was not completely automatic. The operator, who plans the position of the welding torch for each weld bead in a layer, applies the process. Further, he made weld bead size decisions based on the joint width. Once the welding system was started, it tracked the bead location as the groove width changed, controlled the torch height, and can adaptively vary bead size relative to joint width. This flexible technology will minimize the susceptibility to defects during erection welding.

Prediction of Flux Cored Arc Welding (FCAW) Parameters and Bead Geometry in Downhill Position (3F)

2014 ◽  
Vol 660 ◽  
pp. 342-346
Author(s):  
Nik Mohd Baihaki Abd Rahman ◽  
Abdul Ghalib Tham ◽  
Sunhaji Kiyai Abas ◽  
Razali Hassan ◽  
Yupiter H.P. Manurung ◽  
...  
Keyword(s):  
Arc Welding ◽  
Weld Bead ◽  
Welding Parameter ◽  
Welding Parameters ◽  
Bead Geometry ◽  
Weld Bead Geometry ◽  
Absolute Deviation ◽  
High Productivity ◽  
Flux Cored Arc Welding ◽  
Wide Range

The robot can perform Flux Cored Arc Welding (FCAW) at high productivity and consistency in quality. The quality of the welding depend on the selection of welding parameter and deposition geometry. These input has to be known before the start of production, generally the welding operator will obtain the information through experimental trial and error. This project planned to develop a tool that can advise the choice of welding parameter that produce quality weld bead with desired geometry. This research focused on the correlation of heat input on weld bead geometry and the range of welding parameter for fillet design welded in downhill direction (3F). From the correlation trend-line equations and welding parameter population boundary, the weld bead geometry and welding parameter for quality deposit are predicted. Consequently two calculators were developed to display the values digitally. The deviation of predicted bead geometry from actual welding is less than 1mm. Mean Absolute Deviation (MAD) is less than 0.4mm, accuracy is good. A wide range of welding parameters can be generated for quality welding at desired bead geometry.

scholarly journals Análise da influência dos parâmetros de soldagem no processo a arco submerso

2020 ◽  
Vol 1 (49) ◽  
pp. 94
Author(s):  
Marília Aires Bezerra ◽  
João Vitor da Silva Negreiros ◽  
Jomar Meireles Barros ◽  
Divanira Ferreira Maia ◽  
Marcos Mesquita da Silva
Keyword(s):  
Base Metal ◽  
Welding Current ◽  
Strong Relationship ◽  
Weld Bead ◽  
Welding Parameters ◽  
Bead Geometry ◽  
Weld Bead Geometry ◽  
Welding Torch ◽  
Definition Of ◽  
Submerged Arc

This work aimed to analyze the influence of welding parameters on weld bead geometry when applied to the submerged arc process. Specifically, the project carried out: the construction of a welding torch support and flow reservoir, as well as the analysis of the weld bead geometry as a function of the welding parameters. To achieve these objectives, a prototype support for the welding torch in CAD software was created and then fabricated by machining, preparation of the base metal and definition of welding parameters. From then on, welding began. The results showed that the supports provided a good performance for the welding and the geometries of the beads showed a difference in their structure regarding the occurrence of porosity in some beads, having a strong relationship with the stress and the type of flux employed. The contact tip to work distance (CTWD) showed a tendency to decrease current when it increased. In addition, welding current and welding energy showed similar behavior when influencing weld bead geometry. That is, when the current and welding energy increased the height decreased and the width increased.

scholarly journals Multi-Seam Tracking With a Portable Robotic Welding System in Unstructured Environments

2022 ◽  
Author(s):  
Shuangfei Yu ◽  
Yisheng Guan ◽  
Zhi Yang ◽  
Chutian Liu ◽  
Jiacheng Hu ◽  
...  
Keyword(s):  
Forward Direction ◽  
Seam Tracking ◽  
Robotic Welding ◽  
Production Environment ◽  
Welding Torch ◽  
Tracking Process ◽  
Starting Point ◽  
Low Efficiency ◽  
Working Parameters ◽  
Welding System

Abstract Most welding manufacturing of the heavy industry, such as shipbuilding and construction, is carried out in an unstructured workspace. The term Unstructured indicates the production environment is irregular, changeable and without model. In this case, the changeable workpiece position, workpiece shape, environmental background, and environmental illumination should be carefully considered. Because of such complicated characteristics, the welding is currently being relied on the manual operation, resulting in high cost, low efficiency and quality. This work proposes a portable robotic welding system and a novel seam tracking method. Compared to existing methods, it can cope with more complex general spatial curve weld. Firstly, the tracking pose of the robot is modeled by a proposed dual-sequence tracking strategy. On this basis, the working parameters can be adjusted to avoid robot-workpiece collision around the workpiece corners during the tracking process. By associating the forward direction of the welding torch with the viewpoint direction of the camera, it solves the problem that the weld feature points are prone to be lost in the tracking process by conventional methods. Point cloud registration is adopted to globally locate the multi-segment welds in the workpiece, since the system deployment location is not fixed. Various experiments on single or multiple welds under different environmental conditions show that even if the robot is deployed in different positions, it can reach the starting point of the weld smoothly and accurately track along the welds.

Correlation between Welding Parameter and Bead Geometry of Flux Cored Arc Welding (FCAW) in Horizontal Position (2F)

2014 ◽  
Vol 564 ◽  
pp. 549-554
Author(s):  
Nik Mohd Baihaki Abd Rahman ◽  
Abdul Ghalib Tham ◽  
Sunhaji Kiyai Abas ◽  
Razali Hassan ◽  
Yupiter H.P. Manurung ◽  
...  
Keyword(s):  
Heat Input ◽  
Arc Welding ◽  
Weld Bead ◽  
Welding Parameter ◽  
Welding Parameters ◽  
Bead Geometry ◽  
Automatic Welding ◽  
Trend Line ◽  
Flux Cored Arc Welding ◽  
Good Prediction Accuracy

A robotic system can convert the semi-automatic Flux Cored Arc Welding (FCAW) to an automatic welding system. The critical requirement in automated welding process is that the optimal welding parameter has to be set before welding start. These input welding parameters cannot be easily guessed unless one has the knowledge. Only very specific range of heat input that produces quality weld deposition. The correlation between the heat input and fillet weld bead can be displayed in a unique trend-line graph. Mathematical formulas that match the trend-line profile can be used to create a prediction calculator that displays the digital values of weld bead geometry when welded at a specific range of heat input. Small Mean Absolute Deviation between predicted and measured geometry means good prediction accuracy. With this correlation chart, the welding parameter for quality weld bead can be selected and the geometry of FCAW weld deposition in 2F position can be predicted accurately without trial and error.

A modified version of MATLAB application window for predicting the weld bead profile and stress–strain plot of AA5052 CMT weldment using ER4043

SIMULATION ◽  
2021 ◽  
pp. 003754972110315
Author(s):  
B Girinath ◽  
N Siva Shanmugam
Keyword(s):  
Strain Curve ◽  
Weld Bead ◽  
Welding Parameters ◽  
Bead Geometry ◽  
Hybrid Technique ◽  
Stress Strain Curve ◽  
Stress Strain ◽  
Weld Bead Geometry ◽  
Inference System ◽  
Engineering Stress

The present study deals with the extended version of our previous research work. In this article, for predicting the entire weld bead geometry and engineering stress–strain curve of the cold metal transfer (CMT) weldment, a MATLAB based application window (second version) is developed with certain modifications. In the first version, for predicting the entire weld bead geometry, apart from weld bead characteristics, x and y coordinates (24 from each) of the extracted points are considered. Finally, in the first version, 53 output values (five for weld bead characteristics and 48 for x and y coordinates) are predicted using both multiple regression analysis (MRA) and adaptive neuro fuzzy inference system (ANFIS) technique to get an idea related to the complete weld bead geometry without performing the actual welding process. The obtained weld bead shapes using both the techniques are compared with the experimentally obtained bead shapes. Based on the results obtained from the first version and the knowledge acquired from literature, the complete shape of weld bead obtained using ANFIS is in good agreement with the experimentally obtained weld bead shape. This motivated us to adopt a hybrid technique known as ANFIS (combined artificial neural network and fuzzy features) alone in this paper for predicting the weld bead shape and engineering stress–strain curve of the welded joint. In the present study, an attempt is made to evaluate the accuracy of the prediction when the number of trials is reduced to half and increasing the number of data points from the macrograph to twice. Complete weld bead geometry and the engineering stress–strain curves were predicted against the input welding parameters (welding current and welding speed), fed by the user in the MATLAB application window. Finally, the entire weld bead geometries were predicted by both the first and the second version are compared and validated with the experimentally obtained weld bead shapes. The similar procedure was followed for predicting the engineering stress–strain curve to compare with experimental outcomes.

Study and Implement on Key Technologies of Ship-Welding Mobile Robot

2010 ◽  
Vol 44-47 ◽  
pp. 321-325
Author(s):  
Liang Hua ◽  
Lin Lin Lv ◽  
Ju Ping Gu ◽  
Yu Jian Qiang
Keyword(s):  
Mobile Robot ◽  
Control Method ◽  
Structure Design ◽  
Seam Tracking ◽  
Precision Positioning ◽  
Positioning Control ◽  
Controlling System ◽  
Welding Torch ◽  
Driven System ◽  
And Control

The key technilogies of ship-welding mobile robot applied to ship-building in plane block production line were researched and realized. The mechanical structure design of the robot was completed. The motion-controlling system of of two-wheel differential driving mobile robot was developed. A novel precision positioning control method of welding torch using ultrasonic motors was putforward. The mechanism and control-driven system of precision positioning system for welding torch were completed. The platform of obstacle avoidance navigation system was designed and the strategies of seam tracking, trajectory and posture adjustment were preliminary studied. The methods and results put forward in the paper could act as the base of deep research on the theories and technologies of ship-welding mobile robot.

Aspects Regarding the Achievement of Vertical Welding Joints

2015 ◽  
Vol 1128 ◽  
pp. 254-260 ◽  
Author(s):  
Radu Cristian Seculin ◽  
Barna Fazakas ◽  
Teodor Machedon Pisu ◽  
Mihai Alin Pop
Keyword(s):  
Point Of View ◽  
Steel Plates ◽  
Welding Parameters ◽  
Welding Wire ◽  
Oscillation System ◽  
Welded Steel ◽  
Welding Torch ◽  
Welding Joints ◽  
Protective Gas ◽  
Welding Procedure

The vertical MAG welding procedure is a difficult position to be executed because the trend of the molten bath flowing. This article aims to present the achievement of vertical welding joints with a linear device with a radial oscillation system that should achieve automatic vertical welds and the correlation of the welding parameters with the movement of the welding torch in order to obtain these, using the MAG procedure, protective gas M 21 (82% argon + 18% CO2), welding wire SG2, the material of the welded pieces S 355 JR. Samples will be cut from the welded steel plates and they will be characterized from the mechanical point of view (hardness, microstructure and macrostructure).

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