BIL.TOPIC 1. INTRODUCTION 2. OBJECTIVES 3. THEORY 4. MATERIAL AND TOOLS 5. LABORATORY WORK PROCEDURES 6. LABORATORY WORK RESULT 7. LOGIC 8. REFRENCE 9. CONCLUTION INTRODUCTION GMAW PAGE as well as alternating current. spray. preferred for its versatility. often does not use a shielding gas. Unlike welding processes that do not employ a shielding gas. direct current power source is most commonly used with GMAW. flux cored arc welding. each of which has distinct properties and corresponding advantages and limitations. such as shielded metal arc welding. speed and the relative ease of adapting the process to robotic automation. There are four primary methods of metal transfer in GMAW. when the use of semi-inert gases such as carbon dioxide became common. Today. sometimes referred to by its subtypes metal inert gas (MIG) welding or metal active gas (MAG) welding. can be used. Along with the wire electrode. Further developments during the 1950s and 1960s gave the process more versatility and as a result. . a shielding gas feeds through the welding gun. short-circuiting. it became a highly used industrial process. it is rarely used outdoors or in other areas of air volatility. The cost of inert gas limited its use in steels until several years later. but instead employs an electrode wire that is hollow and filled with flux. GMAW is the most common industrial welding process. GMAW was soon applied to steels because it provided faster welding time compared to other welding processes. which shields the process from contaminants in the air. A constant voltage. but constant current systems. and join. A related process. Originally developed for welding aluminum and other non-ferrous materials in the 1940s. causing them to melt. which heats the workpiece metal(s). The process can be semi-automatic or automatic.Gas metal arc welding (GMAW). is a weldingprocess in which an electric arc forms between a consumable wire electrode and the workpiece metal(s). called globular. and pulsed-spray. GTAW Gas tungsten arc welding (GTAW). A related process. and copper alloys. uses a slightly different welding torch to create a more focused welding arc and as a result is often automated. However. it is significantly slower than most other welding techniques. though some welds. known as autogenous welds. GTAW is most commonly used to weld thin sections of stainless steel and non-ferrous metals such as aluminum. do not require it. A constant-current welding power supply produces electrical energy. higher quality welds. The weld area is protected from atmospheric contamination by an inert shielding gas(argon or helium). which is conducted across the arc through a column of highly ionized gas and metal vapors known as a plasma. The process grants the operator greater control over the weld than competing processes such as shielded metal arc welding and gas metal arc welding. also known as tungsten inert gas (TIG) welding. GTAW is comparatively more complex and difficult to master. magnesium. is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. plasma arc welding. [1] . allowing for stronger. and a filler metal is normally used. and furthermore. By applying intense heat. To ensure student know the prevention of accident during welding.. Upon cooling and solidification.fusion processes of joining (i. soldering. To ensure all student according to the instruction and safety. or more commonly.) in which the mechanical and physical properties of the base of be duplicated at the joint. with an intermediate molten filler metal. metal at the joint between two parts is caused to intermix – directly. the oxy-acetylene flame burn at 6000 ‘F. brazing etc. Theory ARC WELDING Arc welding is one of several fusion processes for joining metals. a metallurgical bond is created. In fact. To know what is a true step when doing a welding. GAS WELDING Oxy-Acetylene welding is one of many types of welding supported by the PRL. . To know the part of GAS WELDING and ARC WELDING. the final well-meant potentially has the same strength properties as the metal of the parts. and with enough skill and practice you can use this types of welding for virtually any metal.OBJECTIVE To know main function of welding. Oxy-acetylene welding is simple in concept – two piece of metal are bought together. To ensure student know the skills of welding.e. It is extremely versatile. and the touching edges are melted by the flame with or without the addition of filler rod. This is in sharp contrast to non . Since the joining is an intermixture of metals. and is the only gas flame that is hot enough to melt all commercial metals. MATERIAL AND TOOLS ARC WELDING ARC MACHINE ELEKTROD . SAFETY HELMET (HEAD SHIELD) WIRE BRUSH GLOVE SAFETY GOGGLE . GTAW . . Stop the process at the end of the work piece. and the correct action improve with practice. 7.Do not hold the filler rod continuously in the molten pool.PROCEDURE ARC WELDING 1. Hold the electrode 60’degrees work angle and 2mm – 3mm above the base metal.Use a no.0mm thick. At the end. Use an electrode code MS6013 or E6013with diameter 2.5mm thick. with the inner core of the flame 3mm above the base metal. Welding then proceeds from left to right(for the right hand) 8.5 bar also for oxygen. 3. 6.2mm 4. 5. The correct technique is hold an electrode at the start position for 1s or 2s and continue until the end of the process. 6. 10. hold an electrode at the last position for 1s or 2s before finishing the process. then light and adjust the torch to neutral flame. Hold that position over a spot just inside the left edge of the base metal until a molten pool is established.Adjust the working pressures to about 0. 3. The frequency of this action will be determined by the size of the weld being deposited. Adjust the ampere around 60 – 100 for electrode diameter 3.2mm.5 bar for acetylene and 0.Welding then proceeds by filler rod being fed or dipped into the molten pool. GAS WELDING 1. 2. 5. 2. Put an electrode at the electrode holder and make sure that there are no movement of electrode at the holder. Prepare a piece of mild steel plate 3. 4. 7. 8.Hold that position over a spot just inside the right edge of the base metal until a molten pool is established. .Hold torch at 90’degree work angle and 30’to 45’degree lead angle.6mm or 3. 9.Prepare a piece of mild steel plate 1. 5 welding tip.Wear appropriate protective gear. and the action with practice.com/search?newwindow=welding+gas+arc workshop&oq=welding+gas+workshop. . Arc and Gas Welding is also give us more skills and preparation when we work outside later. i will never ever forget because these talent is bring us to learn a new thing’s in my studying at these polytechnic and I woul.ask.The frequency of the this action will be determined by size of the weld being deposited. He thought us very well about welding.d like to thank my mechanical workshop lecturer En. The talent that our lecturer have give to us is bring us to a new experience about welding and more information about welding. 3. Besides that. However. These practical also give us advantage when we work together with our team and we also can learn many information through share knowledge together. we learn to use a right tools and materials when doing work at welding workshop.http://www. When we see a result from the work that we have done together. REFRENCES 1.com=welding+gas=arc&oq welding. At the same time. Our teacher always remain us to stay alert in safety while doing a work before and after finish the practice .The correct technique is to dip the filler rod in and out of the poor of the regular interval as the word proceeds.http://www. http://www. CONCLUSION At these practical.com/search?=welding+gas+arc workshop&oq=welding+gas. 10. 2. Other than that we also have been teach by our lecturer how to adjust the volume of the electric.9. we learn about how to joining the plat iron use the Arc and Gas Welding. Google. I want to thanks to lecturer and my friend during learning of arc and gas welding.Conclusion is.google. LOGIC The welding practice is a new skills that i have learn to make a Arc and Gas Welding. we are very grateful when we have finish our work in a sharp time that have given by our lecturer.Kamaruddin Mohd Tamin.