Electrical discharge machining basics pdf

Electrical discharge machining edm has long been the answer for high accuracy, demanding machining applications where conventional metal removal is difficult or impossible. Apr 10, 2015 electric discharge machining edm slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Edm typically works with materials that are electrically conductive, although methods have also been proposed for using edm to machine insulating ceramics 8 9. Edm is less efficient than other cutting methods, and comes with a higher price tag, but is one of the most precise forms of. At its beginning, it was developed as a precision machining method for hard materials. This discharge occurs in a voltage gap between the electrode and workpiece.

The basic electrical discharge machining process is really quite simple. They retain the basic characteristics of their 19th and early 20thcentury ancestors and are still classed as one of the following. Sep 09, 2018 electrical discharge machining is not generally used by novice machinists but learning the basics of the process can help to impress a future employer or bring someone to farm out certain. The electrode is a thin wire, with diameters that typically range from. Electrical discharge machining edm is one of the earliest nontraditional machining processes. It cuts the workpiece with electrical discharge just like a band saw. Therefore, the electrode plays an important role, which affects the material removal rate and the tool wear rate 4.

Small hole edm drilling small hole edm drilling, also known as fast hole edm drilling, hole popper, and start hole edm drilling, uses a guided hollow electrode to drill holes by means of electrical discharge machining by eroding material from the workpiece, as shown in figure 1. Lazarenko in 1943, had introduced the controlled edm procedure for machining materials. An electrical spark is created between an electrode and a workpiece. Known by many other names, including spark machining, arc machining. Electrical discharge machining edm is a process for shaping hard metals and forming deep complex. Electrical discharge machining edm is a comparatively new machining method which has several decades of history since it has been invented. Electrical discharge machining, or edm for short, is a highly accurate machining process during which sparks, or electrical discharges, shape a workpiece by removing material. In electric discharge machining process an arc is produced when two currentcarrying wires are shortcircuited. We do need to know the basics of how edm works, but this doesnt. These sparks strike the surface of the metal, carving out the shape of the electrode.

History of edm in1770s, discovered by joseph priestly. Todays wire electrical discharge machines have many features and improvements from machines manufactured in the past. Much like processes such as laser cutting, edm does not need mechanical force in the removal process. This is wire edm electric discharge machining, a process that can cut any electrically conductive material, hard or soft, even carbide or diamond. Nonengineers on the shop floor team will appreciate its lucid process descriptions that will help them communicate better about edm. Principles of electrical discharge machining and non.

What is electrical discharge machining and how does it work. It is an electrothermal machining process where electrical energy is used to generate electrical spark and material removal mainly occurs due to thermal energy of the spark. We can improve themrr by some modification in the the basic principles of edm which give single discharge for each electrical pulse 44. An electrical discharge machining edm is based on the eroding effect of an electric spark on both the electrodes used. Known by many other names, including spark machining, arc machining and inaccurately. Abstract electrical discharge machining edm is considered one of the main nonconventional machining processes. Electrical discharge machining basics january 9, 2018 joshua machines electrical discharge machining edm has long been the answer for high accuracy, demanding machining applications where conventional metal removal is difficult or impossible. During this machining process, a small portion of metals is also eroded away, leaving a small cater. Wire electrical discharge machining a very thin wire of diameter ranging from 0. Electrical discharge machining addresses a host of other edm topics, including the historical development of edm, basics of the edm machining system and process, the power supply generator, spark voltage, electrode servo systems, and more. With the help of oxygen combined edm process, the mrr can be improved by supply.

A spark occurs in a small gap between the work piece and the. This is the reason why it is considered nontraditional contrary to, for example, the processing with. Electrical discharge machining edm is one of the most widely used nontraditional machining processes. The variable mass, cylindrical plasma model singh, a. Electrical discharge machining edm is a controlled metalremoval process that is used to remove metal by means of electric spark erosion. Picture a band saw, but instead of a saw blade there is a thin wire, positioned vertically or at an angle, with which you can cut in any xy direction. State of the art electrical discharge machining edm. The spark is visible evidence of the flow of electricity. On this channel you can get education and knowledge for general issues and topics. Edm process is based on thermoelectric energy between the work piece and an electrode. Electrical discharge an overview sciencedirect topics. Today robots are available that can feed various machines, such as a milling machine, wire edm, and a ram edm. The old timers out there might also find it interesting reading and it always pays to refresh your memory. Electrical discharge machining an overview sciencedirect.

To describe the physical reactions in the edm process unit iii basic components of electrical discharge machining. A thermoelectric model of material removal during electric discharge machining. Edm and electrical discharge machining, are the same and are interchangeable, as is electro discharge machining, as edm is often described within technical papers from europe and asia. Dry electrical discharge machining edm is a modification of the oil edm process in which the liquid dielectric is replaced by a gaseous dielectric. Electric discharge machining edm the literature shows the basis of edm with the discovery of the erosive effect of electric discharges or sparks during the year 1770 by the english chemist joseph priestly 1. Pdf electrical discharge machining edm is one of the earliest nontraditional machining processes.

Edm electrical discharge machining edm, or electrical discharge machining is a process that uses an electrical current to displace material from a workpiece. Developed in the mid 1970s in the mid 1980s, the edm techniques were transferred to a machine tool today,it is a viable technique that helped shape. Electric discharge machining edm linkedin slideshare. Anywhere from 1,000 to 100,000 sparks are generated on and off between the electrode and the metal per second. Checkout all of the training guide resources we have to offer, with links to the related online video or dvd. Edm works by eroding material in the path of electrical discharges that form an arc between an. Electrical discharge machining edm is one of the most extensively used nonconventional material removal processes. The origin of electrical discharge machining goes back to 1770, when english scientist joseph priestly discovered the erosive effect of electrical discharges. Electrical erosion leads to bearing damage and consequently premature bearing failure. Electrical discharge machining machining metals free 30. Unit ii the electrical discharge machining process. Mar 11, 2016 applications of electric discharge machining process.

The merits of the squirrel cage induction machine are. Pdf electro discharge machining edm process is a nonconventional and non contact machining operation which is used in industry for. Wedm is a newer acronym referring specifically to wire edm. Status of recent developments and research issues of. This study investigates the effects of different types of gas air, nitrogen, and mixture of argonair on the machining characteristics of dry edm of m35 workpiece material. Electrical discharge machining is a machining method primarily used for hard metals or those that would be very difficult to machine with traditional techniques. The individual parameters influence the machining process individually in edm optimization is required for the parameters, in order to get desired machining process. Wire machining ram machining other edm processes electrical discharge milling electrical discharge grinding electrical discharge dressing ultrasonic aided edm abrasive electrical discharge grinding micro electrical discharge machining micro wire edm mole edm double rotating electrodes edm. Wire electric discharge machining wire edm youtube. The first stage of damage is not visible to the naked eye.

So, due to this, edm is particularly useful in machining of small holes, orifices, slots in diesel fuel injection nozzles, airbrake valves and aircraft engines etc. Electrical discharge machining free download as powerpoint presentation. Edm is less efficient than other cutting methods, and comes with a higher price tag, but is one of the most precise forms of cutting available today. Mar 25, 2017 electrical discharge machining process works on the basic principle of spark generation and metal removed by spark erosion.

Wire electrical discharge machining edm is one of the greatest innovations affecting the tooling and machining industry. Lazarenko had the idea of exploiting the destructive effect of an electrical discharge and developing a. Electrical discharge machining edm uses controlled electric sparks to erode the metal in a workpiece, and this method is now a well established machining process for high power applications. Priestly identified the impact of electrical discharges. Cnc machining basics engineers need to know r and r. The first part of this presentation provides a brief educational overview of the electrical discharge machining process edm second, a detailed analysis of when,why and where edm can provide a huge benefit in the engineering, design and implementation of the overall tool manufacturing process. Surface integrity can be as good as or better than a ground surface 10,11.

If you continue browsing the site, you agree to the use of cookies on this website. Basics of electrical discharge machining the origin of electrical discharge machining goes. Electrical discharge machining, or edm, is a nontraditional method in which material is removed from a workpiece using thermal energy. Electrical discharge machining process works on the basic principle of spark generation and metal removed by spark erosion. Electrical discharge machining edm, electrode, spark, workpiece, gap, conductivity. Dielectric fluid flushes away particles, cools the work and electrode, prevents fusion of. Basic principles and functions of electrical machines.

Machining tutorials abrasive machining overview basic machining and fitting cnc computerized numerically controlled cnc overview computer aided technologies overview cutting fluids in machining cyberman machining, metalworking, manufacturing electrical discharge machining fundamentals of cnc grinding basics grinding glossary metalworking. Electric discharge machining edm slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Basics of electrical discharge machining the roots of electric discharge machining can be dated way back to 1770 after j. Lazarenko had the idea of exploiting the destructive effect of an electrical discharge and developing a controlled process for machining. There are many manual, benchtop sinkers that have been converted to water. The book also describes the development of electrical discharge machining edm, the edm system and process, the edm sparking system, the power supply generator, spark voltage, electrode servo systems, dielectric systems, ionization and electrode wear, chips, the edm surface, dc arcing, different kinds of edm, automatic servo systems. Understanding electrical discharge machining 29 automation and edm here is an example in which one may use their imagination to become more competitiveusing automatic production cells. Sme offers numerous training guides across the many different industry areas that make up the manufacturing world.

Electrical discharge machining used on hard metals works with electrically conductive materials 3. It is also known as spark machining or spark eroding process principle in this process, electrical energy is used to generate the spark between the tool and workpiece submerged under the dielectric medium so that material removal takes place from the surface of the workpiece by local melting or vaporization. Analysis of dry electrical discharge machining in different. Electric discharge machining edm ppt topics for seminar. Wire cut edm, also known as wire electrical discharge machining, or wire edm is a method of cutting or shaping conductive materials with a thin electrode that follows a precisely programmed path. This electric spark produces intense heat with temperatures reaching 8000 to 12000 degrees celsius. Introduction to and advantages of electrical discharge machining. This paper is intended to give you a better understanding and basic overview of the fundamentals, features and practical uses of wire edm.

The resulting spark discharge erodes the workpiece to form a desired final shape. Electrical discharge machining, or edm, shapes metal by creating sparks that melt tiny portions of the workpiece, and is an exceptionally diverse process that generates no cutting forces. Electrical discharge machining edm, marc lecuyer youtube. Edm has a myriad of applications in the worlds of aerospace, automotive, defense, extrusion, electronics, food and beverage, medicine, and stamping. Electrical discharge machining is the edm fundamentals sourcebook, indispensable to students and apprentices. Electrical discharge machining, edm is one of the most accurate manufacturing processes available for creating complex or simple shapes and geometries within parts and assemblies. Edm and electrical discharge machining, are the same and are. Feb 26, 2015 references a b theoretical models of the electrical discharge machining process. Jun 19, 2014 electrical discharge machining, or edm, shapes metal by creating sparks that melt tiny portions of the workpiece, and is an exceptionally diverse process that generates no cutting forces.

The spark generated by this process produces heat, which remove metal by erosion and evaporation. Edm machining process is also known as spark erosion machining. This process has brought dramatic improvements to industry in accuracy, quality, productivity, and earnings. Edm spark erosion is same as electric spark which burn a small hole in a piece of metal through witch it contacts. Edm is the thermal erosion process in which metal is removed by a series of recurring electrical discharges between a cutting tool acting as an electrode. Even seasoned edm veterans like greg whiteside, applications manager, at charmilles technologies, say they have learned something from it. In recent years, several researches and methods based on the electrical discharge phenomena have been proposed. Electrical discharge machining edm is the thermal erosion process in which metal is removed by a series of recurring electrical discharges between a cutting tool acting as an electrode and a conductive workpiece, in the presence of a dielectric fluid. Wire electrical discharge machining has become an important nontraditional machining process, as it provides an effective solution for producing components made of difficulttomachine materials. The main attraction of edm over traditional machining processes such as metal cutting using different tools and grinding is that this technique utilises thermoelectric process to erode undesired materials from the workpiece by a series of.