Top PDF Feasibility Study for In-Process Monitoring of Gas Tungsten Arc Welding

Feasibility Study for In-Process Monitoring of Gas Tungsten Arc Welding

Feasibility Study for In-Process Monitoring of Gas Tungsten Arc Welding

R.Sathish et al. [3] explained that Gas Tungsten Arc Welding produces an arc between a tungsten electrode and the work-piece. An inert gas shields the arc, electrode and molten pool from atmospheric contamination. While welding thinner materials, edge joints and flanges, welders generally do not use filler metals. However, for thicker materials filler metal is used. It is a popular technique for joining thin materials in the manufacturing industries. This type of welding achieves a high quality weld for stainless steels and non- ferrous alloys. Compared with Gas Metal Arc Welding, the major limitations of GTAW include its inferior joint penetration and its inability to weld thick materials in a single pass. The threshold for butt-joint penetration when welding stainless steel plates using a single pass GTAW process is only 3 mm. Hence, monitoring for multiple passes has to be considered.
Show more

5 Read more

Joining of Microwave Components by use in Gas Tungsten ARC Welding Process for Space Applications: A Review

Joining of Microwave Components by use in Gas Tungsten ARC Welding Process for Space Applications: A Review

R. Sudhakaran et al. (2014) [8] has conducted his research work on a Chromium-Manganese Stainless Steel used Material apply in Gas tungsten arc welding process. Welding parameters such as welding speed, welding current, welding gun angle and gas flow rate has developed. Researcher has work Central composite response surface methodology with four parameters and five levels was employed for conducting the experiments and used the adequacy of the developed model was checked using ANOVA. Weld quality of the weld joint is also highly influenced by the microstructure of the weldment. Researcher also investigates the influence of welding gun angle on the microstructure examination of the weldment. The microstructure study concentrated on the grain structure, presence of carbides and formation of ferrite, austenite and marten site in the weldment. Result researcher has also observed obtained from the present investigation helps in quickly selecting the required process parameters to achieve the desired Pitting resistance equivalent number and weld quality.
Show more

5 Read more

A Review on Alloy Steel Welded by Plasma Arc Welding and Gas Tungsten Arc Welding for Comparative Study of Mechanical Properties

A Review on Alloy Steel Welded by Plasma Arc Welding and Gas Tungsten Arc Welding for Comparative Study of Mechanical Properties

Gas-tungsten arc welding (GTAW), also known as tungsten inert gas (TIG). Tungsten Inert Gas welding (TIG) is the old name for TIG welding process was developed in the late 1930s when a need to weld magnesium became apparent. The process now known as gas tungsten arc welding GTAW and the new name became popular in the technical books. The Gas Tungsten Arc Welding (GTAW) process is applicable when the highest weld quality is required. It can be used to weld almost all types of metals. The operator has excellent control of heat input, and vision is not limited by fumes or smoke from the process. TIG welding consist of Welding torch, non-consumable electrode, argon and helium as a shielding gas and its main application are Ferrous and various non-ferrous metal. Join various dissimilar metals together. Good for fabrication such as aircraft and race car frames, Used for welding thinner metal parts.
Show more

6 Read more

Modelling of Gas Tungsten Arc Welding Pool under Marangoni Convection

Modelling of Gas Tungsten Arc Welding Pool under Marangoni Convection

Abstract Due to lack of comprehensive experimental studies on welding processes, and to better understand the mechanisms behind these processes, especially the weld pool shape variations suspected due to Marangoni Effect or surface tension shear stress, a two-dimensional simulation model was developed to study the physics of gas tungsten arc welding (GTAW). Experimental spot-welds on Ti-5Al-5Mo-5V-3Cr was carried out to compare to the model for crucial clues such as, the magnitude of Marangoni convectional stress that is difficult to determine experimentally; and to estimate the Enhancement Factor, an artificial parameter incorporated into the model proven to account for any discrepancies between simulated results and experimental weld pool shapes, due to lack of viscosity temperature dependent data as well as flow instabilities. The model confirmed that Marangoni Convection is indeed the most dominant force in shaping the weld pool, followed by thermal buoyancy force and electromagnetic force. As the investigation went on, the validity of past welding simulations assuming a constant flow scheme was examined, concluding with the recommendation of applying a laminar flow regime at the initial welding times and turbulent flow with elapsing welding time to effectively eliminate simulation inaccuracies.
Show more

17 Read more

A Study on the Corrosion Behavior in Sea Water of Welds Aluminum Alloy by Shielded Metal Arc Welding, Friction Stir Welding and Gas Tungsten Arc Welding

A Study on the Corrosion Behavior in Sea Water of Welds Aluminum Alloy by Shielded Metal Arc Welding, Friction Stir Welding and Gas Tungsten Arc Welding

elements, is one of the most extensively used alloys because it has desirable properties such as weldability, machinability and corrosion resistance. Major applications of this alloy include its use in aircraft and aerospace components and in the transportation industry [2; 3]. The corrosion resistance of aluminum alloy welds is determined in part by the type of alloy, the filler alloy and the welding process. For aluminum alloys, gas metal arc welding (GMAW) and gas tungsten arc welding (GTAW) are frequently used in welding processes [4-8]. The friction stir welding (FSW) process developed in 1991 by The Welding Institute has also been employed successfully. The advantages of FSW over arc welding processes include improved mechanical properties and reduced microstructural change[9-11]. Few studies have been published on the corrosion and welding of aluminum alloy 6061 [12-15]. According to Nikseresht et al., Fe-rich coarse intermetallic particles act as a cathodic region during the corrosion of 6061 alloy weldment in 3.5 wt. % NaCl. In addition, the weld metal (Ecorr=-704 mV vs. SCE) had better corrosion resistance than the base metal (Ecorr=-728 mV vs. SCE)[6]. In another study, Fahimpour et al. demonstrated that 6061 joined by FSW had higher corrosion resistance than GTAW in seawater solution. However, they reported that both welded regions were susceptible to corrosion attack [4]. Paglia and Buchheit found that aluminum alloy 6061 welded by FSW was susceptible to localized corrosion correlated with precipitate-free zones and coarse precipitates, such as Mg (Zn 2 , AlCu). As noted, the localized corrosion began with pitting and propagated as intergranular
Show more

9 Read more

Mathematical Modeling of Acoustic Signals Generated During Gas Tungsten Arc Welding Process

Mathematical Modeling of Acoustic Signals Generated During Gas Tungsten Arc Welding Process

Abstract—Adoption of alternative advanced approaches for monitoring the ongoing welding can impart a transcendental process-control and can worthily substantiate the regulation of produced weld quality. Acoustic emission analysis, being a highly effective technology has paved way by facilitating the investigation of defects while operation is going on. Essential precise quantification has been carried out for inducing interrelationship of the response variables with the input parameters to predict further behavior of weld and rectification of these process parameters so that unintended defects during gas tungsten arc welding (GTAW) can be minimized. To verify the adequacy and agreeability of designed model, a corroborating evaluation has been performed.
Show more

8 Read more

Influence of Welding Processes on the Exposure of Duplex Stainless Steel Alloy 2205 Using Gas Tungsten Arc Welding and Gas Manual Arc Welding.

Influence of Welding Processes on the Exposure of Duplex Stainless Steel Alloy 2205 Using Gas Tungsten Arc Welding and Gas Manual Arc Welding.

Abstract - In this work, an investigation on the influences of welding processes on the exposure of Duplex stainless steel (DSS) Alloy 2205 using Gas Tungsten Arc Welding and Gas Manual Arc Welding was carried out. The Duplex stainless steel (DSS) Alloy 2205 containing 22%Cr, 5%Ni, ferritic-austenitic material is an emerging class of stainless steel currently being selected for a variety of applications especially where corrosion is of major concern. It have good mechanical properties and high resistance to all forms of corrosion combined with its high strength-to-mass ratio. These properties allow for savings both in terms of structural weight and maintenance costs. In this work, the Gas Tungsten Arc (GTAW) and the Shielded Metal Arc (SMAW) welding processes were used to weld a 200mm x 16.53mm thick duplex alloy 2205 stainless steel pipe to determine which of the processes will cause susceptibility of the alloy to intergranular corrosion at the grain boundaries. Various tests were carried out on transverse specimens cut out from the welds made with both processes. These tests included metallurgical, compositional analysis across the weld profiles, hardness, and tensile test. The test results for the compositional analysis showed an insignificant depletion of chromium from 22.06 at the weld cap to 19.96 at the root of the TIG weld. This depletion is not enough to cause sensitization although there were likely precipitates in the weld and HAZ from the Microstructural analysis. The hardness across the welds profile revealed that there was a uniform distribution of hardness across the MMA weldment when compared to the TIG weld which dropped drastically at the weld metal region from 337.2 and 328.7 to 256.5 and 252.0 at the face and root respectively. The mechanical properties of both welds have not shown any major deviations from the standard Alloy SAF 2205 properties. They are within the acceptable range. The test results obtained indicated that with proper control and monitoring of the welding parameters, the SMAW can be effectively used to weld the Alloy 2205 with comparable high quality of properties.
Show more

8 Read more

Studies on Weldability of Powder Processed Fe 0 35P 0 15C Alloy Using Gas Tungsten Arc Welding Process

Studies on Weldability of Powder Processed Fe 0 35P 0 15C Alloy Using Gas Tungsten Arc Welding Process

The objective of this study was to investigate the weldability of an iron-based powder metal alloy (Fe-P-C) using the gas tungsten arc welding process (GTAW) with two different filler metals. Optical microscopy revealed that for the Fe-P-C alloys, the fusion-welded zone was free of porosity and cracks. The thickness of the slab was 4 mm. The heat affected zone did not show excessive hardness. The SEM image of the fracture specimen showed elongated dimples. X-Ray mapping confirmed the absence of Fe3P. EPMA was used to determine the ability of carbon in preventing the segregation of P to the grain boundaries. Tensile tests showed that the failures of the specimens occurred always in the base metal with tensile strength slightly superior to the value of unwelded samples. As a result, this investigation showed the feasibility of joining iron- based powder metal alloys by the GTAW process, especially while welding the Fe-P-C alloy.
Show more

19 Read more

Effects Of Electrode Melting Rate On Safe Welding Fumes In Gas Tungsten ARC Welding

Effects Of Electrode Melting Rate On Safe Welding Fumes In Gas Tungsten ARC Welding

welding fumes determines the biological activity of the welding fume. Therefore, investigating and understanding the relationship between the welding fume Particle size distribution (PSD) and the arc welding parameters becomes inevitable [9]. Based on numerical methods, research has been done for prediction of particle concentration using Computational Fluid Dynamics (CFD) but the simulated results frequently have some divergence from the experimental results [10]. Fume generated by the shielded metal arc welding (SMAW) process may be a cause for concern due to possible health problems experienced by individuals in the welding industry after long-term exposure. Welding fume particles may cause metal fume fever, and perhaps more importantly, manganese- or chromium related poisoning after inhalation and ingestion into the human body. For example, it has been proposed that long term, low concentration doses of Mn are linked to nervous system disorders[11]. Studies have also shown that welders working with stainless steels who have had cases of lung cancer may be due to possible hexavalent chromium exposure, although there has been no direct evidence linking the cancer to welding fume exposure[12]. Occupational exposure limits (OEL), which are revised quite regularly, determine the amount of these compounds and elements that may be ingested without becoming harmful to human tissues. Though epidemiological reactions to the different compounds present in welding fume are important, they are beyond the scope of this study, which was designed to characterize the fume particles produced by metal joining processes [13].
Show more

5 Read more

Monitoring Gas Metal Arc Welding Process by Using Audible Sound Signal

Monitoring Gas Metal Arc Welding Process by Using Audible Sound Signal

of noise spectra gravity. He stated that within a wide range of the observed parameters there is a direct connection with the emitted noise. He also discovered that an unsuitable flow rate of shielding gas and its distribution, welding material dirtiness and non-uniformity of joint edge configuration have an effect on emitted noise. In 1994 a system for real-time analysis of weld quality in an arc welding process was patented [7]. The acoustic signals generated during the welding process are sampled and digitalized. The digitalized signals are transformed into frequency domain and then divided into a plurality of frequency bands. The average power for each frequency band is calculated and used as input to an artificial neural network for analysis of weld quality. A monitoring method using different statistic parameters to evaluate welding process stability was developed at the Faculty of Mechanical Engineering in Ljubljana [8] to [11]. Some authors believe that surrounding noise, which is not a result of the welding process, obstructs analysis of measured signals and might be considered as one of the most important obstacles for the acoustic monitoring technique, [4], [6] and [12]. From the available literature it can be seen that in the gas shielded arc-welding process, which most important parameters that have an influence on the emitted sound, are arc stability, metal transfer and oscillations of the molten pool. However, a deeper understanding of the relation between physical processes and the generation of sound is needed to overcome obstacles of pure statistical approach in the use of acoustic signals for on line monitoring. The present study is focused on establishing a theoretical and experimental base to implement acoustic monitoring of the welding processes in industrial environment. By a detailed analysis of each part of the acoustic signal, we tried to find the correlated sound source in time and space. Only investigations of audible sound (between 20 and 20000 Hz) generated during GMAW in short circuiting mode are discussed in this paper.
Show more

12 Read more

Experimental Study of Mechanical Properties of 5083 Aluminium Alloy Using Gas Tungsten Arc Welding

Experimental Study of Mechanical Properties of 5083 Aluminium Alloy Using Gas Tungsten Arc Welding

weld pool. The gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) welding processes are very often used for welding of these alloys. However, gas tungsten arc welding (GTAW) process is generally preferred because it produces a very high quality welds. Distortion is the major problem in welding of thin sections. However, the distortion is controlled in pulsed and magnetic arc oscillation GTAW process. Metallurgical advantages of pulsed and magnetic arc oscillation weld that are frequently reported in the literature includes grain refinement in the fusion zone, reduced width of HAZ, less distortion, control of segregation, reduced hot cracking sensitivity and reduced residual stresses [6].
Show more

8 Read more

Process Parameters Optimization of an Aluminium Alloy with Pulsed Gas Tungsten Arc Welding (GTAW) Using Gas Mixtures

Process Parameters Optimization of an Aluminium Alloy with Pulsed Gas Tungsten Arc Welding (GTAW) Using Gas Mixtures

curring in the fusion zone. The main aim of pulsing is to achieve maximum penetration without excessive heat built-up. The use of high current pulses is to penetrate deep and cater for longer arc period at lower current. Deep penetration in pulsed current welding is produced by arc pressure at peak for longer durations [4]. In addi- tion to this argon-helium gas mixture offers certain ad- vantages by increasing heat input of the arc during weld- ing. Argon is known for stable arc with better arc ignition whereas helium provides higher thermal conductivity. There exists a linear relationship between heat input of a weld and maximum temperature at a given distance from the weld centre line. It shows that pulsed arc welds are cooler and exhibit less thermal distortion than conven- tional GTA welds of the same penetration [5]. Heat input is typically calculated as follows:
Show more

7 Read more

Design Of Automatic Tool Changer For Welding Gun Tip

Design Of Automatic Tool Changer For Welding Gun Tip

2.10 MIG Gun Parts 11 2.11 TIG Welding Torch Parts 12 2.12 Spot Welding Parts 12 2.13 A Man Manually Using SMAW Welding 13 2.14 Spot Welding Gun That Attached To An Arm Robot 14 2.15 Welding Gun Tip/Contact-Tube Location In MIG Welding 14 2.16 Varieties Of Electrode Tip 15 2.17 Wore And Deformed Electrode Tip 16 2.18 Hand Held Electrode Dresser 17 2.19 Automatic Tip Dresser 18 2.20 Steam Power Textile Machine 19 2.21 Fully Automated Production Line 20 2.22 One Of The Product Of CAD 23 2.23 Solidworks Logo 26 2.24 Design Using Solidworks 27 2.25 Design Stress Analysis Using Solidworks 27 2.26 An Assembly Of Drive Shaft 28 2.27 Automation Studio 29 2.28 The Application Of Automation Studio 29
Show more

24 Read more

Suppressing Aluminum Carbide in Welding Aluminum Silicon Carbide Composite

Suppressing Aluminum Carbide in Welding Aluminum Silicon Carbide Composite

µm thick. Having the silver interlayer reduced ~3% number of fractured reinforcing particles in the weld. Lee et al. [16] friction welded 6092/SiC/17.5p composites and considered the effects of axial force, rotation speed, tool feed rate, lead angle, and plunge depth as process variables. Excessive abrasive wear of the stirrer was recognized, and a suitable coated stirrer was sought; an inexpensive boron carbide coating was tried unsuccessfully despite of its inherent low coefficient of friction. The optimally welded composite had tensile strength of 300 MPa (43.5 ksi) which was 65% of the parent material strength. After a post-weld solution heat treating and aging to the T6 condition, the joint strength reached up to 426 MPa (61.9 ksi) which is 93% of the parent material’s strength. Friction welding, however, produced a soft weld with hardness of 40 R B compared to 80 R B of the parent material. Recognizing wear of a stirrer
Show more

14 Read more

Reduction of Valve Scrap in Plasma Transferred Arc Welding

Reduction of Valve Scrap in Plasma Transferred Arc Welding

Once the equipment is set up and the welding sequence is initiated, the plasma and shielding gases are switched on. A pilot arc is then struck between a tungsten alloy electrode and the copper alloy nozzle within the torch (nontransferred arc mode), usually by applying a highfrequency open-circuit voltage. When the torch is brought in close proximity to the workpiece or when the selected welding current is initiated, the arc is transferred from the electrode to the workpiece through the orifice in the copper alloy nozzle (transferred arc mode), at which point a weld pool is formed . The PAW process can be used in two distinct operating modes, often described as the melt-in mode and the keyhole mode.The melt-in-mode refers to a weld pool similar to that which typically forms in the Gas Tungsten Arc Welding (GTAW) process, where a bowl shaped portion of the workpiece material that is under the arc is melted.The power source, which supplies the main power for the welding system, is usually supplemented with a sequence controller and control console. The sequence controller sequences the timing of gas flow, arc initiation, main welding current control, and any up-slope and downslope parameters.
Show more

5 Read more

Usability of arc types in industrial welding

Usability of arc types in industrial welding

In order to control heat input and reduce spatter gener- ation and fumes, power sources have been developed with the ability to release one drop for a sequence of arc and pulsed time. The arc uses direct current (e.g. pulsed GMAW) or alternative current (e.g. AC-GMAW) with different current waveforms. A pulsed arc can be used in all welding positions and with all base material thicknesses in both manual and automatic welding systems. Out of position welding is also possible due to the lower than aver- age current level. Because of the low heat input, this mode is suitable for filling gaps. It is widely used in the GMAW of aluminium (Kah et al. 2012). The method is suitable for welding all standard and high performance grades of stainless steel when nickel base or stainless steel filler metals are used. High alloy steels can also be welded by
Show more

12 Read more

Parameter-Properties Relationship Of Thin Plate Welding By Coldarc Technology

Parameter-Properties Relationship Of Thin Plate Welding By Coldarc Technology

ColdArc technology is one of the techniques that used by Gas Metal Arc Welding (GMAW) process but the modification in parameter sector where can produce the particularly low level of heat during welding process with specific filler rod. With this advantage, the thin plate can be welded with strong bond thus produce a lightweight of the automotive part with the high- strength thin plate. Therefore, it can save costs and protect the environment (Goecke, 2005)

24 Read more

Report

Report

Properties of aluminium Tungsten Inert Gas Welding Joint preparation and procedures for TIG welding Tungsten electrode Filler rod ^ Welding current Welding technicque Pre-heating Anodizi[r]

35 Read more

Experimental Investigation of Friction Stir Welding and TIG Welding for Al-6082

Experimental Investigation of Friction Stir Welding and TIG Welding for Al-6082

Commercial aluminum plate of thickness 6mm was selected as work piece material for the present experiment. Al plate was cut with dimension of 120mm×50mm with help of band saw and grinding done at the edge to smooth the surface to be joined. After that surfaces are polished with emery paper to remove any kind of external material. After sample preparation, aluminum plates are fixed in the working table with flexible clamp side by side and welding done so that butt joint can be formed. TIG welding with Alternating Current (AC) was used in experiments as it concentrates the heat in the welding area. Zirconated tungsten electrodes of diameter 3.4mm was taken as electrode for this experiment. The end of the electrode was prepared by reducing the tip diameter to 2/3 of the original diameter by grinding and striking an arc on a scrap material piece. This creates a ball on the end of the electrode. Generally an electrode that is too small for the welding current will form an excessively large ball, where as too large an electrode will form an satisfactory ball at all. For the first phase of experiment welding parameters selected are shown in table 2. Before performing the actual experiment a number of trial experiments have been performed to get the appropriate parameter range where welding could be possible and no observable defects like undercutting and porosity occurred.
Show more

7 Read more

An Investigation of the Weld Current Characteristics on Twining and Tensile Strength of the AZ31 Alloy Sheet Joint Welded By GTAW

An Investigation of the Weld Current Characteristics on Twining and Tensile Strength of the AZ31 Alloy Sheet Joint Welded By GTAW

Sample paragraph, The entire document should be in cambria font. Type 3 fonts must not be used. Other font types may be used if needed for special purposes. The entire document should be in cambria font. Type 3 fonts must not be used. Other font types may be used if needed for special purposes. In this work the commercial rolled AZ31 magnesium metal alloy sheet of 4 mm thicknesses material was employed. The processes were employed in this examination was butt-welding with GTAW welding manner. Two dissimilar types of weld current were utilized as alternative current and pulsed current, which is preferred for low heat input. The configuration of the commercial AZ31 Mg alloy sheet from a chemical point of view reveals the following percentages: 96% Mg, 3% Al and 1% Zn by weight. Weldment filler is the wire of the same material, which was cut from base metal AZ31
Show more

7 Read more

Show all 10000 documents...

Related subjects