A Novel Measurement and Qualification Method of GMAW Welding Fault Based on Digital Signals

2012 ◽  
Vol 472-475 ◽  
pp. 1201-1205
Author(s):  
Sheng Qiang Feng ◽  
Guo Ping Ling ◽  
Bing Ma ◽  
Sheng Sun Hu
Keyword(s):  
Mahalanobis Distance ◽  
Welding Process ◽  
Welding Current ◽  
The Other ◽  
Digital Signals ◽  
High Quality ◽  
Calculation Results ◽  
Novel Method ◽  
Non Destructive ◽  
Gmaw Welding

Online fault non-destructive detection is crucial to the fabrication of high quality products of welds. In this study, a novel method in the field of weld whose name is Mahalanobis Distance Measurement (MDM) is illustrated and employed to determine whether welding faults have occurred or not. This method is based on an arc method which is employed to get the information of welding voltage and welding current. Through analyzing the calculation results of Mahalanobis Distance of the welding voltage and current signals, the important information of welding process has been obtained. At the meanwhile, whether a fault has occurred or not is decided. In order to verify the effect of the performance of the different width of the gap on the results of Mahalanobis Distance, two widths of the gap generated artificially were chosen: one is 2 mm and the other is 3 mm. The results of the experiment have demonstrated that using the thinking of Mahalanobis Distance to measure the weld faults is feasible.

scholarly journals Hardness analysis on carburized steel weld joint by SMAW using different welding current

2018 ◽  
Vol 204 ◽  
pp. 06009
Author(s):  
Yanuar Rohmat Aji Pradana ◽  
Wahono ◽  
Dicky Tanzila ◽  
Azmi Lukman
Keyword(s):  
Weld Metal ◽  
Weld Joint ◽  
Welding Process ◽  
Welding Current ◽  
Gear Train ◽  
The Other ◽  
Steel Weld ◽  
Additional Material ◽  
Carburized Steel ◽  
Steel Weld Joint

Low-cost weld joint on wear-resist gear train component was introduced for replacing conventional bolted connection to avoid its additional material and holes requirement. This study was concerned on the hardness analysis of carburized steel weld joint generated from SMAW with different welding currents, namely 80, 100, and 120 A. The results indicated that the hardness is decreased at HAZ and subsequently increased at weld metal for all samples. On the other hand, the highest welding current applied during welding shows the highest hardness curve among the other currents up to 226.5±2 HV at weld metal. By micro-and macrostructural analyses, phases evolution during thermal cycle on welding process played the crucial role to determine the hardness of HAZ, while the weld metal hardness was dominantly driven by the carbon-rich element distribution.

scholarly journals A Novel Gel-based Method for Isolation of Stigmas During Controlled Pollination Experiments

2009 ◽  
Vol 58 (1-6) ◽  
pp. 226-233 ◽  
Author(s):  
Tasmien N. Horsley ◽  
Nicoletta B. Jones ◽  
Steven D. Johnson
Keyword(s):  
Sodium Alginate ◽  
Genetic Material ◽  
Current Method ◽  
The Other ◽  
Isolation Method ◽  
High Quality ◽  
Pollination Experiments ◽  
Controlled Pollination ◽  
Novel Method ◽  
Elite Trees

Abstract In forestry, controlled pollination (CP) allows the combining of genetic material of selected elite trees to produce high quality, and consequently high value, seed. The aim of the present study was to develop a novel isolation method that would allow the technique to be conducted without expensive and time-consuming bagging, making CPs on small-flowered eucalypts commercially viable. We compared the current method of isolating inflorescences using exclusion bags to a novel method which uses sodium alginate gel. Sodium alginate was effective in keeping external pollen away from the stigma, since no seed was produced in those treatments that were not manually pollinated but isolated in this way. In addition, flowers hand-pollinated and isolated with sodium alginate produced progeny that were 100% outcrossed with the applied pollen. The exclusion bags, on the other hand, were not as effective in protecting the stigma as seed was produced in those treatments that were isolated with an exclusion bag without being handpollinated. Sodium alginate isolation also increased the efficiency of control-pollinations as the gel was naturally shed, removing the need for operators to return to the tree to remove the isolation material.

A study on welding quality for the automatic vertical-position welding process based on Mahalanobis Distance method

2018 ◽  
Vol 1 (91) ◽  
pp. 31-40
Author(s):  
B.-J. Jin ◽  
M.-H. Park ◽  
T.-J. Yun ◽  
J.-Y. Shim ◽  
B.-Y. Kang ◽  
...  
Keyword(s):  
Mahalanobis Distance ◽  
Welding Process ◽  
Welding Current ◽  
Welding Parameters ◽  
Vertical Position ◽  
Welding Quality ◽  
Distance Method ◽  
Arc Voltage ◽  
On Line ◽  
Arc Welding Process

Purpose: The welding quality and reducing production cost could be achieved by developing the automatic on-line welding quality monitoring system. However, investigation of welding fault to quantify the welding quality on the horizontal-position welding has been concentrated. Therefore, MD (Mahalanobis Distance) method on the vertical-position welding process by analysing the transform arc voltage and welding current gained from the on-line monitoring system has been applied. Design/methodology/approach: The transformed welding current and arc voltage data were taken from the experiment whereby the data number was 2500 data/s. The prediction of Contact Tip to Work Distance (CTWD) to gain best welding quality using the waveform variations were then taken from the experimental results. MD was employed to quantify the welding quality by analysing the transformed arc voltage and welding current. Finally, the optimal CTWD setting has verified the developed algorithms through additional experiments. Two kinds of experiments has been carried out by changing welding parameters artificially to verify the sensitivity and feasibility of WQ (Welding Quality) based on the concepts of MD and normal distribution. Findings: The results represented that WQ was fully capable of quantifying and qualifying the welding faults for automatic vertical-position welding process. Research limitations/implications: The arc welding process on the vertical-position compared to a horizontal-position welding is much more difficult because the metal transfer is influenced by the gravity force. To solve the problem, a new algorithm to monitor and control the welding fault during the arc welding process has been developed. Furthermore, optimization of welding parameters for the vertical-position welding process was really difficult to use the developed algorithms because they are only useful in selecting stored data and not for evaluating the effect of the variation of welding parameters on the weld ability. Practical implications: The developed algorithm could be achieved the highest welding quality at 15mm CTWD setting which the welding quality is 99.50% for the start section and 99.68% at the middle section. Originality/value: This paper proposed a new algorithm which employed the concepts of MD (Mahalanobis Distance) and normal distribution to describe a good quality welding.

Failure Analysis Case Study of a 1.5 Meter Space Flex Harness

2017 ◽  
Author(s):  
Erick Kim ◽  
Kamjou Mansour ◽  
Gil Garteiz ◽  
Javeck Verdugo ◽  
Ryan Ross ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Failure Modes ◽  
Field Of View ◽  
Area Of Interest ◽  
Air Stream ◽  
Novel Method ◽  
Temperature Controlled ◽  
Non Destructive ◽  
Failure Site

Abstract This paper presents the failure analysis on a 1.5m flex harness for a space flight instrument that exhibited two failure modes: global isolation resistances between all adjacent traces measured tens of milliohm and lower resistance on the order of 1 kiloohm was observed on several pins. It shows a novel method using a temperature controlled air stream while monitoring isolation resistance to identify a general area of interest of a low isolation resistance failure. The paper explains how isolation resistance measurements were taken and details the steps taken in both destructive and non-destructive analyses. In theory, infrared hotspot could have been completed along the length of the flex harness to locate the failure site. However, with a field of view of approximately 5 x 5 cm, this technique would have been time prohibitive.

Metodología para el desarrollo de trayectorias en la aplicación por el proceso de soldadura GMAW en un robot industrial

2019 ◽  
pp. 1-4
Author(s):  
Josué Rafael Sánchez-Lerma ◽  
Luis Armando Torres-Rico ◽  
Héctor Huerta-Gámez ◽  
Ismael Ruiz-López
Keyword(s):  
Mechanical Properties ◽  
Automotive Industry ◽  
Industrial Robot ◽  
Welding Process ◽  
High Strength ◽  
Test Material ◽  
Advantages And Disadvantages ◽  
Application Characteristics ◽  
Joining Process ◽  
Gmaw Welding

This paper proposes the development of the methodology to be carried out for the metal joining process through the GMAW welding process in the Fanuc LR Mate 200iD industrial robot. The parameters or properties were considered for the application to be as efficient as possible, such parameters as speed of application, characteristics of the filler material, gas to be used as welding protection. The GMAW welding process can be applied semiautomatically using a hand gun, in which the electrode is fed by a coil, or an automatic form that includes automated equipment or robots. The advantages and disadvantages of the GMAW welding process applied in a manual and automated way were commented. The mechanical properties of the materials to which said welding can be applied were investigated; The materials with which this type of welding can be worked are the high strength materials, which are used in the automotive industry, for the forming of sheet metal. To know the properties of the material, destructive tests were carried out on the test material to be used, as well as the mechanical properties of the welding.

scholarly journals Multi-Objective Optimization of Resistance Welding Process of GF/PP Composites

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2560
Author(s):  
Guowei Zhang ◽  
Ting Lin ◽  
Ling Luo ◽  
Boming Zhang ◽  
Yuao Qu ◽  
...  
Keyword(s):  
Signal To Noise Ratio ◽  
Welding Process ◽  
Welding Current ◽  
Resistance Welding ◽  
Thermoplastic Composites ◽  
Current Time ◽  
Process Factor ◽  
Welding Equipment ◽  
Lap Shear ◽  
Adhesive Connections

Thermoplastic composites (TPCs) are promising materials for aerospace, transportation, shipbuilding, and civil use owing to their lightweight, rapid prototyping, reprocessing, and environmental recycling advantages. The connection assemblies of TPCs components are crucial to their application; compared with traditional mechanical joints and adhesive connections, fusion connections are more promising, particularly resistance welding. This study aims to investigate the effects of process control parameters, including welding current, time, and pressure, for optimization of resistance welding based on glass fiber-reinforced polypropylene (GF/PP) TPCs and a stainless-steel mesh heating element. A self-designed resistance-welding equipment suitable for the resistance welding process of GF/PP TPCs was manufactured. GF/PP laminates are fabricated using a hot press, and their mechanical properties were evaluated. The resistance distribution of the heating elements was assessed to conform with a normal distribution. Tensile shear experiments were designed and conducted using the Taguchi method to evaluate and predict process factor effects on the lap shear strength (LSS) of GF/PP based on signal-to-noise ratio (S/N) and analysis of variance. The results show that current is the main factor affecting resistance welding quality. The optimal process parameters are a current of 12.5 A, pressure of 2.5 MPa, and time of 540 s. The experimental LSS under the optimized parameters is 12.186 MPa, which has a 6.76% error compared with the result predicted based on the S/N.

scholarly journals Non-destructive handheld XRF study of archaeological composite silver objects—the case study of the late Roman Seuso Treasure

2021 ◽  
Vol 13 (5) ◽  
Author(s):  
Viktória Mozgai ◽  
Bernadett Bajnóczi ◽  
Zoltán May ◽  
Zsolt Mráv
Keyword(s):  
Fluorescence Analysis ◽  
The Body ◽  
High Quality ◽  
X Ray ◽  
Composite Objects ◽  
Mechanical Attachment ◽  
Non Destructive ◽  
Made In ◽  
Late Roman

AbstractThis study details the non-destructive chemical analysis of composite silver objects (ewers, situlas, amphora and casket) from one of the most significant late Roman finds, the Seuso Treasure. The Seuso Treasure consists of fourteen large silver vessels that were made in the fourth–early fifth centuries AD and used for dining during festive banquets and for washing and beautification. The measurements were systematically performed along a pre-designed grid at several points using handheld X-ray fluorescence analysis. The results demonstrate that all the objects were made from high-quality silver (above 90 wt% Ag), with the exception of the base of the Geometric Ewer B. Copper was added intentionally to improve the mechanical properties of soft silver. The gold and lead content of the objects shows constant values (less than 1 wt% Au and Pb). The chemical composition as well as the Bi/Pb ratio suggests that the parts of the composite objects were manufactured from different silver ingots. The ewers were constructed in two ways: (i) the base and the body were made separately, or (ii) the ewer was raised from a single silver sheet. The composite objects were assembled using three methods: (i) mechanical attachment; (ii) low-temperature, lead-tin soft solders; or (iii) high-temperature, copper-silver hard solders. Additionally, two types of gilding were revealed by the XRF analysis, one with remnants of mercury, i.e. fire-gilding, and another type without remnants of mercury, presumably diffusion bonding.

Double-Electrode GMAW Welding Process Research Based on the DSC

2013 ◽  
Vol 668 ◽  
pp. 321-324 ◽  
Author(s):  
Guo Hong Ma ◽  
Jun Nie ◽  
Chao Yang Zhang ◽  
Jia Ye
Keyword(s):  
Magnesium Alloy ◽  
Welding Process ◽  
Alloy Sheet ◽  
Process Research ◽  
Az31b Magnesium Alloy ◽  
Magnesium Alloy Sheet ◽  
Double Electrode ◽  
Az31b Magnesium Alloy Sheet ◽  
Gmaw Welding

Through a large number of technology experiments, finding out the matching parameters of the DE-GMAW welding of the AZ31B magnesium alloy sheet based on the DSC. This paper simply controls the motor based on the DSC to control the welding torches moving comfortably to make the welding process stable to obtain the good weld.

scholarly journals Influence of cutting type and size on rooting of Lavandula dentata L

2012 ◽  
Vol 14 (1) ◽  
pp. 8-11 ◽  
Author(s):  
C.M. Bona ◽  
I.R. Biasetto ◽  
M. Masetto ◽  
C. Deschamps ◽  
L.A. Biasi
Keyword(s):  
Essential Oil ◽  
Vegetative Propagation ◽  
Plant Material ◽  
The Other ◽  
Root Weight ◽  
Root Number ◽  
Polystyrene Foam ◽  
High Quality ◽  
Cutting Propagation ◽  
Superior Clones

Even though the Lavandula species may be propagated by seeds, it should not be the preferred propagation method because it causes a great lack of uniformity. On the other hand, asexually propagated lavender crops would provide more homogeneous crops, and clones from high quality plant material would increase the odds for obtaining a higher quality essential oil. However, problems such as poor rooting and restrict market availability for superior clones have been a problem in vegetative propagation of the Lavandula species. The objective of this work was to define which type and size of cutting is more adequate for cutting propagation of L. dentata, a very productive Lavandula species. Cuttings with 5, 8, 10 or 13 cm and from the apical or basal parts of stems cut from L. dentata stock plants were placed in Plantmax HT® filled polystyrene foam trays and kept under intermittent mist system for two months. Averages of root number, length of the longest root, fresh and dry root weight, and percentage of rooting were evaluated. Apical cuttings combined 97.9% rooting with an average of 13.2 roots per cutting and basal cuttings 93.7% rooting with 2.98 roots per cutting. Apical cuttings with at least 10 cm in length were considered the most adequate for cutting propagation of L. dentata.

scholarly journals Predicting Welding Distortion in a Panel Structure with Longitudinal Stiffeners Using Inherent Deformations Obtained by Inverse Analysis Method

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Wei Liang ◽  
Hidekazu Murakawa
Keyword(s):  
Inverse Analysis ◽  
Welding Process ◽  
Strain Theory ◽  
The Other ◽  
Welding Distortion ◽  
Welding Deformation ◽  
Welded Structures ◽  
Longitudinal Stiffeners ◽  
Manufacturing Accuracy ◽  
Inherent Strain

Welding-induced deformation not only negatively affects dimension accuracy but also degrades the performance of product. If welding deformation can be accurately predicted beforehand, the predictions will be helpful for finding effective methods to improve manufacturing accuracy. Till now, there are two kinds of finite element method (FEM) which can be used to simulate welding deformation. One is the thermal elastic plastic FEM and the other is elastic FEM based on inherent strain theory. The former only can be used to calculate welding deformation for small or medium scale welded structures due to the limitation of computing speed. On the other hand, the latter is an effective method to estimate the total welding distortion for large and complex welded structures even though it neglects the detailed welding process. When the elastic FEM is used to calculate the welding-induced deformation for a large structure, the inherent deformations in each typical joint should be obtained beforehand. In this paper, a new method based on inverse analysis was proposed to obtain the inherent deformations for weld joints. Through introducing the inherent deformations obtained by the proposed method into the elastic FEM based on inherent strain theory, we predicted the welding deformation of a panel structure with two longitudinal stiffeners. In addition, experiments were carried out to verify the simulation results.

Sign in / Sign up

Export Citation Format

Share Document