International Journal For Technological Research In Engineering Volume 3, Issue 3, November-2015 ISSN (Online): 2347 - 4718 REVIEW ON VERIOUS TYPE OF WELDING PROCESS Onkar Patel1, Prakash Kumar Sen2, Gopal Sahu3, Ritesh Sharma4, Shailendra Bohidar5 1Student, Mechanical Engineering, Kirodimal Institute of Technology, Raigarh (C.G.) 2,3,4,5 Lecturer, Mechanical Engineering, Kirodimal Institute of Technology, Raigarh (C.G.) ABSTRACT: In manufacturing process two part are joint is Friction welding necessary where welding is generally use. Welding is a Cold presser welding permanent joint process in this paper discuss in welding Spot welding process there type and its defect and safety process. Seam welding Key word- welding pressure arc. Projection welding Upset but welding I. INTRODUCTION Flash but welding Welding often done by melting the work pieces and filler Percussion welding material is added to form a pool of molten material that cools to become a strong joint, with the pressure, sometimes used 2.2 Non presser welding (fusion welding)-in this type of in conjunction with heat, or by itself, to produce the weld. welding process of joining two piece of metal by application The history of joining metals goes back several millennia, of heat the two parts to be joined are placed together heated with the earliest examples of welding from the bronze Age to molten state often with the addition of filler metal until and the Iron Age in Europe and the Middle East [1]Welding they melt and solidify on cooling . in this welding , the technology which is a high productive and practical joining material at the joint is heated to molten state and then method is widely used in modern manufacturing industry allowed to solidify Such as shipbuilding, automobile, bridge, and pressure vessel Gas welding industry [2]. Welding, the fusing of the surfaces of two work pieces to form one, is a precise, reliable, cost-effective, and Termite welding high- method for joining materials. No other technique is as Electric arc welding widely used by manufacturers to join metals and alloys 1.carbon are welding efficiently and to add value to their products. Most of the metal arc welding familiar objects in modern society, from buildings and submerged arc welding bridges, to vehicles, computers, and medical devices, could plasma arc welding not be produced without the use of welding. goes well atomic hydrogen welding beyond the bounds of its simple description. Welding today inert gas welding – is applied to a wide variety of materials and products, using tungsten ins welding (TIG) such advanced technologies as lasers and plasma arcs. The metallic inert gas welding (MIG) future of welding holds even greater promise as methods are devised for joining dissimilar and non-metallic materials, and for creating products of innovative shapes and III. FUSION WELDING designs.[3]Welding is a process of permanent joining two Fusing two or more bars together by bringing them to a high materials (usually metals) through localised coalescence heat in a forge, and applying pressure to the area being fused resulting from a suitable combination of temperature, by hammer blows. Forge welding is used in several pressure and metallurgical conditions. Depending upon the circumstances: to produce a smooth transition of adjoining combination of temperature and pressure from a high elements; to secure several elements into a bundle (i.e. temperature with no pressure to a high pressure with low leaves, grapes, acorns, basket twist); to join a bundle to temperature, a wide range of welding processes has been another element; to close the ends of a single bar shaped in a developed. ring, oval, or rectangular shape (as in a frame); to join mild steel to high carbon steel (as in an axe bit); or to laminate II. TYPES OF WELDING several bars together to form a billet (as in Damascus There are two type of welding laminate).[5] presser welding non presser welding IV. RESISTANCE WELDING 2.1 presses welding – in this type of welding process pieces Resistance welding is the most commonly used method for of metals are to be joined to a plastic state and then forced joining steel sheets. No filler metal is needed and the heat together by external pressure no fillere material is used in this required for the weld pool is created by means of resistance method plastic welding may be classifieds follows- when a high welding current is directed through the welded work-pieces. An electro-conductive contact surface is Blacksmiths forge welding created between the work pieces by pressing them together. Resistance welding www.ijtre.com Copyright 2015.All rights reserved. 456 International Journal For Technological Research In Engineering Volume 3, Issue 3, November-2015 ISSN (Online): 2347 - 4718 Contact is made using the shape of either the welded surfaces VII. SPOT WELDING of the work pieces or the shape of the electrodes. Spot welding is the most commonly used form of resistance welding. Usually it is used to weld various sheet metals with V. FRICTION WELDING reduced thickness. The weld is discontinued and limited to Friction welding is a solid state welding process that allows one or more spots, with the work pieces usually overlapped. joining of specific material combinations which are It is produced by the generation of heat and pressure, without considered unweldable by conventional techniques. In order filler metal, in a localized area[11] to produce a friction weld, the two components are forced to rotate against each other (friction phase), thereby generating VIII. PROJECTION WELDING heat at the interface. Once the desired upset length or process Projection welding is an electric resistance welding process time has been reached, the rubbing motion stops (braking that uses small projections, embossments, or intersections on phase), the pressure rises (swelling time) and the components one or both components of the weld to localize the heat and are pressed against each other (forging phase) until they are pressure. By doing so, weld current and force is focused into cooled down. The main variables in friction welding are the the small area of the projection, and heat is obtained from the rotational speed, the axial forces during the friction and resistance to the flow of the welding current. Due to this forging phases, and the welding time. The typical heat, the projections collapse and the parts are weld relationship of these characteristics is shown in Fig. 2 which together.[12] illustrates a direct drive friction welding process[6] IX. RESISTENCE BUT WELDING Resistance butt welding is a welding technique that produces coalescence simultaneously over the entire area of abutting surfaces or progressively along a joint, by the heat obtained from resistance to electric current through the area where those surfaces are in contact[13]. Pressure is applied before heating is started and is maintained throughout the heating period. The equipment used for upset welding is very similar to that used for flase . It can be used only if the parts to be welded are equal in cross-sectional area Fig. -1: Variation of the welding parameters with time in X. GAS WELDING direct drive friction welding.[7] Gas metal arc welding (GMAW) process is an important component in many industrial operations. The GMA welding VI. COLD PRESSER WELDING parameters like welding current, welding speed, arc voltage Cold pressure welding is the establishment of an atom-to- are the most important factors affecting the quality, atom bond between the two pieces to be joined through productivity and cost of welding joint. Weld bead geometry intimate contact between oxide-free areas achieved under directly affects the cost of welding[14] pressure and without the formation of liquid phase. In order to develop this bond, surface films have to be removed or at least reduced in amount. Surface films fall into two categories: - Oxide film: All metals except gold possess an oxide film at room temperature. In most metals the oxide film reaches a limiting thickness in the range 20-100 angstroms at room temperature. - Contaminant film: This film consists of a thin layer of moisture and greases. The best technique, which has proved to be successful in reducing these films, is a combination of chemical and mechanical cleaning. Then, the welding method contains two stages. The first stage of welding involves the formation of overlapped oxide-free metallic areas; this is controlled by: (a) difference on a micro scale of the local plastic strain occurring on matching opposite faces of the weld interface, (b) relative hardness of the metal and its oxide film, and (c) mechanical properties of the oxide. The second stage involves: (a) plastic flow of the metal to the over-lapped areas; stress at which this can take place is in fluent by the stacking fault energy of the metal, and (b) some relative shear displacement at the points where metal cleaned of oxide comes into contact; this is influenced Fig.2. gas welding by surface roughness [8,9,10] www.ijtre.com Copyright 2015.All rights reserved. 457 International Journal For Technological Research In Engineering Volume 3, Issue 3, November-2015 ISSN (Online): 2347 - 4718 XI. THERMITE WELDING operator must then wait for a few minutes before returning to Exothermic reactions between a metal and a metal oxide. work between metallic elements (intermetallic), and the combustion of metals (metal oxidation reactions) are extremely useful sources of energy production and material synthesis for numerous applications. For example, the thermite welding process was first demonstrated in 1898 and continues to be the most frequently used method for the field welding of rail road track[15,16]Other applications for thermite reactions include termite torches for underwater and atmospheric cutting and perforation electronic hardware destruct devices; additives to propellants and explosives for increased performance; pyrotechnic switches; airbag gas generator materials; reactive fragments; high- temperature- stable igniters; free-standing insert able heat sources; devices Fig.4.