Pure oxygen, instead of air, is used to increase the. However, it is still widely used for a variety of applications. Mostly oxy acetylene gas is used for all general purpose of welding. Weld the metals with oxyacetylene process on different joints and positions. Gas welding manual metal arc welding gasshielded metal arc. In this video we will discuss about welding defects. What is welding defects types, causes and remedies. The spark lighter is used to ignite the oxyacetylene mixture at the tip of cutting torch. Gas welding and cutting oxyfuel welding, commonly referred to as oxy welding or gas welding is a process of joining metals by application of heat created by gas flame. Acetylene gas virtually all the acetylene distributed for welding and cutting use is created by allowing calcium carbide a man made product to react with water. Natural gas is the preferred fuel gas in areas where it is available. Air products welders handbook migmag welding principles gas shielded metal arc welding is a semiautomatic process which is suitable for both manual and mechanised operation. In welding, the defects often found in fusing due to lack of fusion, lack of penetration. Difference between arc welding and gas welding mech4study.
The oxyacetylene torch is a safe tool if used properly. Pdf often times, autoexhaust oxyacetylene maintenance weld by local. When mixed together in correct proportions within a handheld torch or blowpipe, a relatively hot flame is produced with a temperature of about 3,200 deg. Following table shows the useful fuel gases for gas welding with their calorific values and temperatures. Oxyacetylene welding also known as oxyacetylene welding uses an oxyfuel gas flame can be applied with or without pressure can be applied with or without the use of filler materials 5. Weve worked hard to produce gas welding kits to suit as many applications, and pockets, as possible. Gas cylinder is filled either by oxy acetylene gas, hydrogen gas, natural gas or other flammable gas. Oxyacetylene welding is a very common welding process that dates back to 1890s, wherein oxygen and acetylene are used as the two major welding gases. Many different energy sources can be used for welding including gas flames, electric arcs, electric resistance, lasers, electron beams, friction, molten metal baths and ultrasound. In this welding process, mostly oxyacetylene gas is used as working fuel gas. Oxyfuel equipment is versatile, lending itself to welding, brazing, braze welding, silver soldering, metal heating for bending and forming and oxyfuel cutting. Copper spiral mixer designed for uniform, freeflowing flame.
Neutral flame is used for normal welding of steel, cast iron etc, gas welding techniques leftward welding. Oxy acetylene welding is a welding process manually, in which the surfaces to be joined, which is warming to melt by a gas flame oxyacetylene with or without filler metal, where the connection process without emphasis. The fuel gas selection is depends on the welding material. Necessary considerations for gas welding fuel gases fuel gas for gas welding used is acetylene due to its high temperature in the flame. Oxyacetylene welding is the most commonly used gas welding technique. It is a welding process that melts and joins the metals by heating them with a flame caused by a reaction of fuel gas and oxygen. A mixture of oxygen and acetylene, burns as an intense focussed flame, at approximately 3,500 degrees centigrade. The process of joining may also take place by other means of riveting or by fastening nut and bolts. In order to discuss the various aspects of welding, cutting and brazing safety, first we need to cover the basics in this first module. The use of oxygen and acetylene as welding gases dates back to the 1890s. These are the two main types of welding used in different joining process. This version has been adapted for online use from hses current printed version.
This is one of the most important types of welding process commonly called as oxyacetylene or oxyfuel welding. Resistance welding butt spot seam projection percussion ivthermit welding vsolid state welding friction ultrasonic diffusion explosive vinewer welding electronbeam laser viirelated process oxy. In addition to the purposes of welding connecting, gas welding can also be used as preheating, brazing, cutting, and hard facing. Safety and health at work for gas welding and flame cutting 2 1. As the electrode movement is manually controlled hence it is termed as manual metal arc. Mig metal inert gas mag metal active gas co2 carbon dioxide a low voltage 18. When the flame comes in contact with steel, it melts the surface forming a molten pool, allowing welding. Weldingdefinition, type detail, advantage disadvantage. The safe use of compressed gases in welding, flame cutting and allied processes this is a freetodownload, webfriendly version of hsg9 first edition, published 1997. The bcga code of practice cp7 recommends the gauges are checked annually and replaced every 5 years. Welding is a process of joining two or more similar or dissimilar metals with or without the application of heat, with or without the application of pressure, with or without the application of filler material therefore, in this article, i will be explaining all types of welding process in detail with the help of a tree diagram. Today i am going to tell you about difference between arc welding and gas welding. Oxyacetylene gas welding is commonly used to permanently join mild steel. This is the most unwanted defect of all the other welding defects.
The gas flow rate is controlled by a pressure adjusting screw which sets the outlet gas pressure. Pass a written test on safety and operation procedures on the oxyacetylene unit with a minimum of 100 accuracy. Gas welding is a type of liquid state welding process, in which fuel gases burns to generate heat. This oxyacetylene welding tip features a copper spiral mixer designed for a uniform, freeflowing flame. Oxy acetylene welding leaving certificate engineering notes. Then an authorized professional should determine, if the defects are repairable or not. Download as docx, pdf, txt or read online from scribd. The various types of external defects with their causes and remedies are listed below. Oxy acetylene welding ofw fundamentals pressure settings. Gas welding kits is a bit of a generic term, as gas equipment can be used for a wide variety of purposes, not just welding. The preheat flame is composed of fuel gas and oxygen at a proper mixture ratio to produce maximum flame. When the flame comes in contact with steel, it melts the surface forming a molten pool, allowing welding to. This heat is used to melt interface surfaces of welding plates which are held together to form a joint.
Oxyacetylene welding uses a mixture of acetylene gas and oxygen gas to feed the welding torch. When choosing equipment, the most important thing to consider is exactly what you want to be able to do, as this will determine what type of fuel gas you can use. Gas welding oxyacetylene airacetylene oxyhydrogen iii. Oxy acetylene gas welding kits the welders warehouse. In handbook of plastics joining second edition, 2009. The flame is hot enough to fuse the metal surfaces together for welding. The fuel gas commonly acetylene, when mixed with proper proportion of oxygen in a mixing chamber of welding torch, produces a very hot flame of about 57005800f.
The combination of oxygen and acetylene produces a flame temperature over 6000 degrees fahrenheit making it ideal for. One should reject the items and put them temporarily on hold. Heres an oxyacetylene welding kit that handles a broad range of cutting, welding, and heating applications. Competencies given a functional oxyfuel gas unit, instruction and demonstration of use, each student will be able to. This welding tip is an ideal replacement tip for the heavy duty welding kit. Separate or perform parts sufficiently to allow for shrinkage of welds. Action what should be done when weldingdefects are detected. Oxyacetylene welding acetylene gas plants manufacturer. This gas mixture also provides the highest flame temperature of available fuel gases, however acetylene is generally the most expensive of all fuel gases. The safe use of compressed gases in welding, flame cutting. Mig also is referred to as gmaw gas metal arc welding. Gas welding is probably the oldest of the welding processes and gas welding equipment is arguably the most versatile.
The same type of oxyfuel welding apparatus is used in all cases, but the torch welding tip size could be changed depending on the amount of btu heat output. Oxyacetylene welding is a very common welding process. Thereby the gas welding may be known as oxyacetylene welding oaw. And the filler rod is inclined at 300400 in opposite direction. Normally these cylinders have maroon line to indicate it. Oxygenacetylene welding, or gas welding, is a process which relies on combustion of oxygen and acetylene. In 1903 edmond and charles picard discover this welding type. Manual metal arc welding, department of training and.
Fusion weldinga welding process that joins metals by heating them to be a melting point and allowing them to fuse or flow together. Hot gas welding can be used to weld practically any shape or size of component, and the equipment has probably the lowest cost of all the plastic welding techniques. Welding, cutting, and brazing welding is a process that joins materials together by melting a metal work piece along with a filler metal to form a strong joint. Wear welding gloves, helmet, leather apron, welding chaps, leather boots, welding goggles, and other personal protective equipment to help prevent weld burns and injury. Gas welding is also named as oxyfuel gas welding ofw.
Oxyfuel welding commonly called oxyacetylene welding, oxy welding, or gas welding in the united states and oxyfuel cutting are processes that use fuel gases or liquid fuels such as gasoline and oxygen to weld or cut metals. The nice thing about the calcium carbide method of producing acetylene is that it can be done on almost any scale desired. Difference between arc welding and gas welding april 18, 2016 february 15, 2018 admin 15 comments comparison, welding. Oxygen and acetylene gases are mixed in equal volumes. Must have bulk oxygen, and natural gas supply pressure of 10 psi minimum. An ideal weld or good weld should be such that adequate fusion exists between the filler metal and edge preparation together with good penetration. Oxyacetylene welding, commonly referred to as gas welding, is a process which relies on combustion of oxygen and acetylene. One should determine the cause and try to implement a corrective action to avoid future reoccurrence. You can buy the book at uk and most good bookshops. Gas cylinders and acetylene generator, regulators, hoses with fittings, goggles. The other equipments serves the same function as in case of oxyacetylene gas welding.
Welding cracks can be present at the surface, inside. On this channel you can get education and knowledge for general issues and topics. Comes with hoses, welding and cutting torches, goggles, tip cleaners and striker. Low unit cost and good quality in all but very thin pieces. Fundamentals of gas cutting and welding ced engineering. The flux may be used to deoxidize and cleanse the weld metal. Oxyacetylene welding is simple in concept two pieces of metal are brought together, and the touching edges are melted by the flame with or without the addition of filler rod. The regulator has two gauges, a high pressure gauge for the gas in the cylinder and a low pressure gauge for the gas being fed to the torch. It can be used for cutting steel, welding steel, brazing and for heating metal. Cutting of metals by means of flame has many advantages over other methods, specially when the metal is of irregular shape. Welding defects are generated in a welding job due to the faulty or poor technique used by the inexperienced or unskilled welder or due to fundamental difficulties in the welding operation.
Two of these techniques are used to weld flat joints and one is used for allposition welding. The oxyacetylene torch can be used for various tasks. Welding includes joining methods as diverse as fusion welding, forge welding, friction welding, braze welding, brazing, soldering and explosion welding. However, if it is used incorrectly, serious injury can occur to you and the equipment. Oxyfuel oxyacetylene welding a guide to gas welding.
There are three main techniques used in oxyfuel welding. We guarantee this product to be free from defects in materials and workmanship 90 days from the date of purchase. Identify gas and arc welding defects and adopt remedies. Hot gas torches are very light and easy to use in awkward positions, and are ideally suited for field repairs where the component is too. In this welding the tip of the torch is held at 600700 to the plates.
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