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. Safety in gas welding, cutting and similar processes. Plasma cutting processes are broken down according to where they are used above and on the water and under the surface of water. Pure oxygen is then directed through the nozzle at the heated area. The power density on the cutting front is fsin this causes melting which is then blown away by the drag forces from the fast flowing gas stream. Basics of laser cutting knowledge you must know machinemfg. Now open both cylinders valves no specific order but only open the acetylene tank about a 12 turn, the oxygen should be opened all the way. Flame cutting, oxyfuel cutting, fuel gas cutting and oxygen. Immediately close the cylinder valves, both theimmediately close the cylinder valves, both the fuel gas and oxygen, if it is safe to do so.
Safety in gas welding, cutting and similar processes page 3 of 11 preventing fire from heat, sparks, molten metal or direct contact with flame the flame from an oxyfuel gas torch often called a blowpipe is a very powerful source of ignition. Chalk line guides may be drawn on the cutting surfaces to mark the cut. If the fie cannot be put out at once, evacuate theif the fie. Oxygenacetylene welding, or gas welding, is a process which relies on combustion of oxygen and acetylene. Flame cutting oxy fuel cutting a method to cut thick steel. Plasma cutting can be use for precision cutting on gauge material up to 6 thick stainless.
Laser cutting indian institute of technology bombay. At this temperature of around 960c depending on type of alloy, the steel has lost protective properties against oxygen and is still solid. You will learn more about gas welding in chapter 5. Good tips, and info to help you have a better understanding of what this thing can do. However, for heavy sections of steel 1 inch and greater, oxyfuel is still preferred since oxyfuel is typically faster and, for heavier plate applications, very high capacity power supplies are required for. The harris products group is a world leader in metal working products used in the brazing, soldering, welding, cutting and gas distribution industries. It even goes over the more advanced uses for gas welding such as brazing, oxyfuel cutting and flame heating. The oxyfuel process is the most widely applied industrial thermal cutting process because it can cut thicknesses from 0. Oxyacetylene welding oxyacetylene, commonly known as oxyfuel, is one of the. Principle of plasma cutting with transferred arc electrode cathode nozzle plasma gas kerf cutting direction workpiece anode plasma arc. The preheat flame is composed of fuel gas and oxygen at a proper mixture ratio to produce maximum flame. In cutting, molten material is ejected from the workpiece by a focused assistgas jet applied from the top. When cutting with the nitrogen, the purity of the gas should reach 99.
The difference between acetylene vs lpg propane as a. The primary uses today are welding, brazing and cutting. The basic plasma cutting process involves creating an electrical channel of superheated, electrically ionized gas i. Mapp gas can be highly pressurized and stored in the same way as lpg, and it is a favorite of hobby welders. The material can now be burned or pushed out of the groove by the cutting gas. Chapter 4 gas cutting the common methods used in cutting metal are oxygas flame cutting, air carbonarc cutting, and plasmaarc cutting.
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. The beginners guide to gas welding machines4u magazine. However, mapp torches provide a very hot flame, almost as hot as oxyacetylene, and the gas can be used for industrial metalcutting operations. This is accomplished by a compressed gas oxygen, air, inert and others depending on. Never use matches or a cigarette lighter to ignite the oxyacetylene torch. All of these topics are indepth and are another stepping stone in understanding gas welding and gas welding equipment. This presentation covers the basic concepts of gas welding and gas cutting. Once an electric arc is introduced to the gas, ionized gas or plasma is created, the fourth state of matter. For a typical oxygas cutting outfit, also referred to as a cutting rig figure 41, you need. Other fuel gases such as lpg or propane produce a reactive secondary flame that interferes with the molten metal, making them unsuitable for welding.
The effective cutting distance from the workpiece is approximately 23 times that of acetylene. Before cutting, the cutting torch has to preheat the steel to ignition temperature at. For greater accuracy, use straight edges, shaped guide bars, or templates to steady the hand and guide the cut. Environmental impacts of the oil and gas industries. And in most cases it used to cut steel plate thickness more than 20 mm, since oxy fuel cutting usually brings big tolerance. The equipments used for gascutting is similar to that of gaswelding except that the welding torch is replaced by a special designed 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. Watch out for whipping limbs and branches when cutting smaller material. 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. Flame cutting also known as oxy fuel cutting, it is to use the heat burned from oxy fuel gas, to cut steel materials or the hard metals to the panels or profiles required. In welding, the weld bead is protected from oxygen contamination with a gentle and unfocused cover gas applied from the side. Gas welding is widely used for maintenance and repair work because of the ease in transporting oxygen and fuel cylinders.
Technical parameter in the early stage of laser cutting, the user must determine the setting of the machining parameters by the test operation. Careless use of oxyfuel torches has caused many fires. Materials which are cut in this way include the majority of those that can be melted i. 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.
There are many variations of the arcwelding process. An oxygas cutting outfit usually consists of a cylinder of acetylene or mapp gas, a cylinder of oxygen, two regulators, two lengths of hose with fittings, and a cutting torch with tips fig. The difference between laser cutting and welding is the focal head and gas delivery method used. Mud is used to maintain well pressure and wall stability. Is also less likely to overheat, and thus not create an atmosphere for flashback tips are flush drilled and used a lot closer to the cutting face, thus dramatically increasing the risk of getting foreign matter into the holes. At the bottom of the kerfthe melt is thicker due to deceleration of the film and surface tension retarding the melt from leaving. Cnc plasma cutting refers to the cutting of metals using a plasma torch controlled from a computer.
Esab invented plasma cutting in 1955, and weve never stopped developing ways to. Drilling during drilling, a drilling mud is continuously circulated between the well and the platform through a riser pipe. If this is not done there will be starvation of oxygen at the nozzle when the cutting oxygen lever is depressed. If youd like to learn more about ablative laser cutting, check out this article on micronscale manufacturing fiber lasers vs co 2. 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. Doing so reduces the chance that the log will roll over on the sawyer if the sawyer cuts a supporting limb. The torch may also be clamped to circle guides or wheeled carriages. Cutting of metals by means of flame has many advantages over other methods, specially when the metal is of irregular shape.
Its pretty safe when used properly, but not safe at all when not used properly. Plasma cutters operate by forcing a gas or compressed air at high speeds through a nozzle. The two most common types of laser cutting machines are fiber laser and co 2 co 2 lasers use an electromagnetically stimulated. Oxyfuel cutting is a thermal cutting process that uses oxygen and fuel gas such as acetylene, propane, mapp, propylene and natural gas to cut through materials.
Once you learn the basics and begin to practice ofw, you will find the process is adaptable to brazing, cutting, and heat treating. However, before learning about the equipment, you must be familiar with the gases most often used to fuel the cutting equipment. Mig metal inert gas mag metal active gas co2 carbon dioxide a low voltage 18. This course describes the basic concepts of oxyfuel welding and cutting including what equipment and. Whats more to automate on oxy fuel cutting then merely flame onoff. How to use, and get better at using a acetylene torch. How to operate an oxyacetylene cutting torch snapguide. The basics before cutting, the cutting torch has to preheat the steel to ignition temperature at the starting point. Given its dominance in the sheet metal cutting industry, this article focuses on laser fusion cutting. Acetylene gas c2h2 is dissolved in acetone liquid and stored at 250 psi, in a specially designed cylinder. Oxyfuel cutting torches use a copper tip with a series of holes arranged in a circle to deliver a mixture of a fuel gas and oxygen to create a preheat flame. First close the acetylene knob all the way until the flame is extinguished. It is essential when using a combined outfit type 3 or lw to open the oxygen valve or the shank fully. Fundamentals of gas cutting and welding cedengineering.
Fundamentals of gas cutting and welding ced engineering. Safety in gas cuttingsafety in gas cutting if a flash back does our. With smaller thicknesses, plasma cutting is inferior to laser cutting in terms of cutting quality, but it is more economical when cutting thicker sheet metal. The company was formed in 2006 with the merger of harris calorific, inc. This is not a comprehensive oxyfuel safety course by any means but i tried. To vent the atmosphere from the acetylene hose, open the gas valve on the cutting torch handle until you hear gas escaping, then observe the lowpressure gauge to see if the pressure remains steady during flow and ensure that you have this regulator set correctly. In modern steelage the steelmakers cut iron and steel by oxyacetylene, oxyhydrogen, oxy propane, oxynatural gas cutting blowpipes easily, speedily, and cleanly. Cutting torch tips for oxygen acetylene cutting youtube. Plasma cutting is typically easier for the novice to master, and on thinner materials, plasma cutting is much faster than oxyfuel cutting.
For more information, please refer the books mentioned in the. The extremely high temperature of the arc causes the material to be melted or heated to ignition temperature. Wear flame resistant clothing when gas welding or cutting. Plasma cutting is the fastest cutting process on carbon steel, aluminum, or stainless steel. The basics in order to discuss the various aspects of welding, cutting and brazing safety, first we need to cover the basics in this first module. Begin and complete cuts with a sharp chain and high chain speed.
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