Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Electric discharge machining (EDM) is a machining process that uses electrical discharges to remove material from a conductive workpiece. There are two main EDM processes - die sinking and wire cutting. Die sinking involves an electrode progressively eroding a workpiece cavity to its shape. Wire cutting uses a continuously fed wire electrode to cut complex profiles. EDM can machine all conductive materials regardless of hardness and produces parts with good accuracy and surface finish.
Electric discharge machining (EDM) is a thermoelectric process that uses sparks produced by electric discharges to remove material from conductive workpieces. Short duration sparks erode material by melting and vaporizing small amounts from both the tool and workpiece electrodes. Effective dielectric flushing is needed to remove debris from the gap and improve machining accuracy and surface finish. Process parameters like voltage, current, pulse duration and frequency can be controlled to achieve different material removal rates and surface finishes for roughing and finishing operations. Common electrode materials include graphite, copper and brass due to their machinability and electrical conductivity.
1) Dielectric fluids used in EDM must provide an oxygen-free environment for machining, have strong dielectric resistance to prevent electrical breakdown, and ionize during sparking. Common dielectric fluids are kerosene and deionized water.
2) Electrode materials for EDM tools must have high electrical and thermal conductivity for efficient sparking and less tool wear, and high melting points to prevent material removal from the tool. Common materials are graphite, copper, and brass.
3) Proper flushing of dielectric fluid is important to remove debris from the spark gap and prevent short-circuiting, improving surface finish and material removal rate. Common flushing techniques are pressure, reverse, suction, jet
The document discusses various thermal energy-based material removal techniques, focusing on electrical discharge machining (EDM) and wire EDM. EDM works by using electrical sparks to erode metals, with the sparks controlled by a power supply. Wire EDM uses a continuously moving wire to remove material through controlled repetitive sparks in a dielectric fluid. Both processes can machine hard materials and leave minimal burrs. The document also covers laser beam machining, which uses a focused laser beam to melt, vaporize, or ablate material.
This document provides an overview of the manufacturing technology course ME-202 on nontraditional machining processes. The document discusses several advanced machining processes including electrical discharge machining (EDM), electrochemical machining (ECM), laser beam machining (LBM), electron beam machining (EBM). For each process, the document outlines the basic principles, mechanisms of material removal, advantages, limitations and applications. Examples are given of parts made using these advanced processes such as turbine blades, fuel injection nozzles, and knee implants.
This document provides an overview of electro discharge machining (EDM). It discusses the working principle of EDM, which involves using electric sparks to erode metal to the desired shape. The key components of EDM are described, including the power generator, dielectric fluid, electrode tool, and fixture. Characteristics of EDM like its ability to machine hard materials regardless of strength are summarized. Advantages include machining complex shapes and tight tolerances, while disadvantages include slow removal rates and electrode wear. Applications of EDM mentioned are drilling micro-holes, cutting threads, and machining hardened alloys.
Electro Discharge Machining (EDM) is a non-traditional machining process that uses electrical sparks to remove material. In EDM, an electric spark is generated between an electrode tool and conductive workpiece submerged in a dielectric fluid. This spark removes microscopic amounts of material through thermal erosion. EDM can machine hard metals and complex shapes. It produces a recast layer on the workpiece surface with altered properties that may require post-machining treatment. Common applications of EDM include die and mold making.
The document discusses various advanced manufacturing processes that use thermal energy or electrical discharges to remove material from a workpiece. It focuses on electrical discharge machining (EDM) and wire EDM. EDM works by sparking electrical discharges between an electrode and workpiece submerged in dielectric fluid to erode away material. Key advantages of EDM are its ability to machine hard metals and create complex shapes. The document also covers laser beam machining which uses a focused laser beam to melt, vaporize, or ablate material from the workpiece.
Electric discharge machining (EDM) is a machining process that uses electrical discharges to remove material from a conductive workpiece. There are two main EDM processes - die sinking and wire cutting. Die sinking involves an electrode progressively eroding a workpiece cavity to its shape. Wire cutting uses a continuously fed wire electrode to cut complex profiles. EDM can machine all conductive materials regardless of hardness and produces parts with good accuracy and surface finish.
Electric discharge machining (EDM) is a thermoelectric process that uses sparks produced by electric discharges to remove material from conductive workpieces. Short duration sparks erode material by melting and vaporizing small amounts from both the tool and workpiece electrodes. Effective dielectric flushing is needed to remove debris from the gap and improve machining accuracy and surface finish. Process parameters like voltage, current, pulse duration and frequency can be controlled to achieve different material removal rates and surface finishes for roughing and finishing operations. Common electrode materials include graphite, copper and brass due to their machinability and electrical conductivity.
1) Dielectric fluids used in EDM must provide an oxygen-free environment for machining, have strong dielectric resistance to prevent electrical breakdown, and ionize during sparking. Common dielectric fluids are kerosene and deionized water.
2) Electrode materials for EDM tools must have high electrical and thermal conductivity for efficient sparking and less tool wear, and high melting points to prevent material removal from the tool. Common materials are graphite, copper, and brass.
3) Proper flushing of dielectric fluid is important to remove debris from the spark gap and prevent short-circuiting, improving surface finish and material removal rate. Common flushing techniques are pressure, reverse, suction, jet
The document discusses various thermal energy-based material removal techniques, focusing on electrical discharge machining (EDM) and wire EDM. EDM works by using electrical sparks to erode metals, with the sparks controlled by a power supply. Wire EDM uses a continuously moving wire to remove material through controlled repetitive sparks in a dielectric fluid. Both processes can machine hard materials and leave minimal burrs. The document also covers laser beam machining, which uses a focused laser beam to melt, vaporize, or ablate material.
This document provides an overview of the manufacturing technology course ME-202 on nontraditional machining processes. The document discusses several advanced machining processes including electrical discharge machining (EDM), electrochemical machining (ECM), laser beam machining (LBM), electron beam machining (EBM). For each process, the document outlines the basic principles, mechanisms of material removal, advantages, limitations and applications. Examples are given of parts made using these advanced processes such as turbine blades, fuel injection nozzles, and knee implants.
This document provides an overview of electro discharge machining (EDM). It discusses the working principle of EDM, which involves using electric sparks to erode metal to the desired shape. The key components of EDM are described, including the power generator, dielectric fluid, electrode tool, and fixture. Characteristics of EDM like its ability to machine hard materials regardless of strength are summarized. Advantages include machining complex shapes and tight tolerances, while disadvantages include slow removal rates and electrode wear. Applications of EDM mentioned are drilling micro-holes, cutting threads, and machining hardened alloys.
Electro Discharge Machining (EDM) is a non-traditional machining process that uses electrical sparks to remove material. In EDM, an electric spark is generated between an electrode tool and conductive workpiece submerged in a dielectric fluid. This spark removes microscopic amounts of material through thermal erosion. EDM can machine hard metals and complex shapes. It produces a recast layer on the workpiece surface with altered properties that may require post-machining treatment. Common applications of EDM include die and mold making.
The document discusses various advanced manufacturing processes that use thermal energy or electrical discharges to remove material from a workpiece. It focuses on electrical discharge machining (EDM) and wire EDM. EDM works by sparking electrical discharges between an electrode and workpiece submerged in dielectric fluid to erode away material. Key advantages of EDM are its ability to machine hard metals and create complex shapes. The document also covers laser beam machining which uses a focused laser beam to melt, vaporize, or ablate material from the workpiece.
This document discusses electric discharge machining (EDM). It describes the working principle of EDM, which uses electric sparks to remove small amounts of material from conductive workpieces and tools. The key components of an EDM system are described, including the power supply, dielectric system, electrodes (tool and workpiece), and servo system. The document explains how EDM uses an electric spark to melt and vaporize small amounts of material from both electrodes. It also discusses factors that influence the EDM process such as electrode material, dielectric fluid, flushing, and process parameters.
This document contains information about a student named Sourabh Tailor with roll number 2013btechme041. It discusses unconventional machining processes including electrochemical machining (ECM) and electric discharge machining (EDM). For ECM, it describes the principles, equipment, electrolyte, tools, advantages, disadvantages and applications. For EDM, it discusses the physical principles, characteristics, tools, dielectric fluid, advantages, disadvantages and applications such as wire EDM and electric discharge grinding.
The document discusses various thermal energy-based material removal techniques, including electrical discharge machining (EDM) and laser beam machining (LBM). It provides details on the EDM process, including how it works using electric sparks to erode metals. Wire EDM and micro EDM are also examined. The document then covers the LBM process, the types of lasers used for different applications like cutting, drilling, and marking. It discusses key laser beam parameters such as beam waist, intensity, and depth of focus. In summary, the document provides an in-depth overview of EDM and LBM processes for removing material using thermal energy.
This document discusses electrical discharge machining (EDM). EDM is a machining process that uses electrical sparks to remove material from a workpiece. In EDM, a tool electrode is moved close to the workpiece and an electric current is applied, creating sparks that erode away material. Key aspects covered include the basic components and setup of an EDM machine, the working principle of how material is removed through electric sparks, important process parameters, and applications where EDM is commonly used such as machining hard metals and complex shapes.
The document discusses various thermal energy-based material removal techniques, focusing on electrical discharge machining (EDM) and laser beam machining (LBM). It provides details on the EDM and LBM processes, including how they work, common applications, advantages, and limitations. EDM uses electric sparks to melt and vaporize material, while LBM uses a focused laser beam. Both processes precisely shape materials by thermal heating without mechanical forces.
Full details of Electroc discharge machine ,Ultrasonic machining, Electro Che...ManojSingh376471
This document provides information on three non-traditional machining processes: electric discharge machining (EDM), ultrasonic machining (USM), and electrochemical machining (ECM). EDM uses electric sparks to erode material away from a workpiece. USM employs abrasive particles and ultrasonic tool vibration to machine brittle materials. ECM removes metal from a workpiece using electrolysis with the workpiece as the anode. Key aspects of each process like operating principles, applications, and important process parameters are described. Diagrams illustrate EDM working, wire EDM, USM setup, and ECM principles.
This document provides an overview of nontraditional machining processes including electrochemical machining (ECM), electro discharge machining (EDM), electron beam machining (EBM), and laser beam machining (LBM). It discusses the basic principles, mechanisms, advantages, limitations and applications of each process. Examples of parts made using these advanced processes and diagrams illustrating the setup and operation are also included. The document is intended to teach students about nontraditional machining as part of a manufacturing technology course.
Electric Discharge Machining (Modern Machining Process)Dinesh Panchal
Electric discharge machining (EDM) is a machining process that uses electrical discharges to remove material from a conductive workpiece. In EDM, a precision-controlled tool electrode is used instead of a cutting tool to remove material via short electrical pulses. This allows EDM to machine hard metals and alloys that cannot be easily machined through conventional methods. The process leaves no burrs and can machine complicated components. Modern EDM uses pulsed DC power supplies to control parameters like voltage, current, frequency, and duty cycle to control material removal rate and surface finish.
Electrical Discharge Machine is an advanced machining method which removes metal by a series of recurring electrical discharges betweenn an electrode and a conductive workpiece, submerged in a dielectric fluid.
Electric discharge machining is an electrothermal machining process that can machine hard conductive materials using electric sparks. It works by applying a potential difference between a tool electrode and workpiece submerged in a dielectric fluid, causing electric sparks that erode away material. Key factors that affect the process include the electric current, pulse duration and frequency, electrode and workpiece gap distance, and dielectric fluid. EDM enables precision machining of complex shapes without mechanical forces and is useful for brittle materials. Applications include drilling micro holes, cutting intricate cavities, and machining hard alloys like turbine blades.
Electric discharge machining (EDM) is a machining process that uses electrical sparks to erode metals. It works by maintaining a precise gap between an electrode tool and a metal workpiece submerged in a dielectric fluid. Repeated electrical sparks are generated to melt and vaporize small amounts of metal from both the tool and workpiece, allowing complex and hard-to-machine shapes to be produced. EDM can machine metals regardless of hardness and without mechanical force, giving it advantages over traditional machining methods for difficult-to-cut materials.
Electrochemical Machining (ECM) has established itself as one of the major alternatives to conventional methods of machining difficult - to - cut materials of and generating complex contours, without inducing residual stress and tool wear.
This seminar is devoted to the study of influences of variable ECM parameters like applied voltage and feed rate keeping other parameters constant on the surface roughness (Ra) using Response Surface Methodology (RSM).
1. Wire electrical discharge machining (WEDM) is a non-conventional thermo-electric process that removes material from a workpiece using a series of electrical sparks between a wire electrode and the workpiece submerged in dielectric fluid.
2. Many factors influence the WEDM process, including wire positioning, flushing pressure, and material properties. Mathematical models are used to understand relationships between process parameters like peak current and duty factor, and performance measures like material removal rate.
3. Experiments are conducted to determine the effects of process parameters like pulse on/off time and servo voltage on material removal rate and surface roughness when machining H13 hot die steel. The optimal settings are identified using statistical techniques
Electro Discharge Machining
Introduction
Process
Process Parameters
Dielectric
Advantages of EDM
APPLICATIONS
Power generator
Wire EDM
ELECTRIC DISCHARGE GRINDING (EDG)
This document discusses electrical discharge machining (EDM) and wire cut EDM. It begins with a brief history of EDM and an overview of the EDM process, including its working principle, important characteristics, and applications. It then focuses on wire cut EDM, explaining its working principle, major components of the process, advantages, and disadvantages. The document concludes by outlining the scope and plan for investigating the effects of process parameters on material removal rate, surface finish, and kerf width in wire cut EDM.
Electrochemical machining (ECM) is a process that removes material from a conductive workpiece using electrical current. In ECM, the workpiece acts as an anode in an electrolyte bath, and material is removed from the workpiece and transported to a cathode tool. ECM can machine complex shapes in a single pass with no cutting forces and leaves the workpiece stress-free. Key factors that affect the ECM process include electrolyte composition and flow, voltage, feed rate, and current density between the tool and workpiece. ECM is used for aerospace, medical, and automotive applications where other machining methods cannot produce the required geometry or precision.
Electric discharge machining (EDM) involves removing material from a workpiece using electrical discharges between two electrodes separated by a dielectric liquid. It was invented in the 1940s by Russian physicists and can machine hard metals and intricate shapes that other methods cannot. The document discusses the history, working principle, material removal mechanism, advantages, and applications of EDM. It also covers technical parameters like electrode materials, dielectric fluids, and process variables that influence the material removal rate.
ELETROCHEMICAL MACHINING BY HIMANSHU VAIDHimanshu Vaid
Electrochemical machining (ECM) is an electrolytic process that removes material from a conductive workpiece acting as an anode using a tool acting as a cathode. Material is dissolved from the workpiece and flows away with the electrolyte. ECM can machine hard materials and complex shapes without thermal or mechanical stresses. It provides better surface finishes than conventional machining and EDM. Micro ECM uses smaller gaps and feature sizes for micromachining. Variations include electrochemical jet etching and laser-assisted jet etching for maskless patterning of thin films. The scanning electrochemical microscope also uses electrochemical reactions for high-resolution imaging and local etching.
Electrical discharge machining (EDM) is a non-traditional machining process that uses electrical sparks to remove metal. The document discusses the history and development of EDM, including key components like the electrode, workpiece, dielectric fluid, and power supply. It describes the basic EDM process and different EDM methods like conventional EDM, wire EDM, and hole drilling EDM. The document also covers EDM applications, innovations like dry EDM and powder-mixed EDM, and concludes with a list of references.
The document summarizes electrodischarge machining (EDM). EDM uses electrical sparks to erode material from a workpiece and tool electrode separated by a dielectric liquid. Key points:
- Material is removed through high-temperature melting and evaporation caused by electrical discharges between the electrodes.
- Process advantages include ability to machine hard materials and produce complex geometries without mechanical forces.
- Factors like pulse characteristics, electrode material properties, dielectric properties influence material removal rate and surface finish.
- EDM leaves a recast layer and heat-affected zone in the workpiece due to high temperatures from sparking.
This document summarizes the various departments and activities of the Gulzar Exploration and Transformation Tank (GETT) research center. It includes departments for faculty and student research, industry-academia collaboration, instrumentation facilities, intellectual property services, entrepreneurship incubation, and more. GETT focuses its research efforts on areas like agritech, healthtech, edutech, and next generation materials. It also lists major research projects and funding received. The document outlines GETT's policies and programs to support innovation, research, and commercialization through incentives, funding, infrastructure, and entrepreneurship resources.
This document provides information about a differential gear including:
1. It lists 4 student names who are presenting on the topic.
2. It describes the main parts of a differential gear including the pinion drive gear, ring gear, differential case assembly, rear drive axles, rear axle bearings, and axle housing.
3. It explains the power flow through a differential gear starting from the drive shaft spinning the pinion gear which turns the ring gear and differential case to spin the sun gears and axles to transfer power to the wheels.
This document discusses electric discharge machining (EDM). It describes the working principle of EDM, which uses electric sparks to remove small amounts of material from conductive workpieces and tools. The key components of an EDM system are described, including the power supply, dielectric system, electrodes (tool and workpiece), and servo system. The document explains how EDM uses an electric spark to melt and vaporize small amounts of material from both electrodes. It also discusses factors that influence the EDM process such as electrode material, dielectric fluid, flushing, and process parameters.
This document contains information about a student named Sourabh Tailor with roll number 2013btechme041. It discusses unconventional machining processes including electrochemical machining (ECM) and electric discharge machining (EDM). For ECM, it describes the principles, equipment, electrolyte, tools, advantages, disadvantages and applications. For EDM, it discusses the physical principles, characteristics, tools, dielectric fluid, advantages, disadvantages and applications such as wire EDM and electric discharge grinding.
The document discusses various thermal energy-based material removal techniques, including electrical discharge machining (EDM) and laser beam machining (LBM). It provides details on the EDM process, including how it works using electric sparks to erode metals. Wire EDM and micro EDM are also examined. The document then covers the LBM process, the types of lasers used for different applications like cutting, drilling, and marking. It discusses key laser beam parameters such as beam waist, intensity, and depth of focus. In summary, the document provides an in-depth overview of EDM and LBM processes for removing material using thermal energy.
This document discusses electrical discharge machining (EDM). EDM is a machining process that uses electrical sparks to remove material from a workpiece. In EDM, a tool electrode is moved close to the workpiece and an electric current is applied, creating sparks that erode away material. Key aspects covered include the basic components and setup of an EDM machine, the working principle of how material is removed through electric sparks, important process parameters, and applications where EDM is commonly used such as machining hard metals and complex shapes.
The document discusses various thermal energy-based material removal techniques, focusing on electrical discharge machining (EDM) and laser beam machining (LBM). It provides details on the EDM and LBM processes, including how they work, common applications, advantages, and limitations. EDM uses electric sparks to melt and vaporize material, while LBM uses a focused laser beam. Both processes precisely shape materials by thermal heating without mechanical forces.
Full details of Electroc discharge machine ,Ultrasonic machining, Electro Che...ManojSingh376471
This document provides information on three non-traditional machining processes: electric discharge machining (EDM), ultrasonic machining (USM), and electrochemical machining (ECM). EDM uses electric sparks to erode material away from a workpiece. USM employs abrasive particles and ultrasonic tool vibration to machine brittle materials. ECM removes metal from a workpiece using electrolysis with the workpiece as the anode. Key aspects of each process like operating principles, applications, and important process parameters are described. Diagrams illustrate EDM working, wire EDM, USM setup, and ECM principles.
This document provides an overview of nontraditional machining processes including electrochemical machining (ECM), electro discharge machining (EDM), electron beam machining (EBM), and laser beam machining (LBM). It discusses the basic principles, mechanisms, advantages, limitations and applications of each process. Examples of parts made using these advanced processes and diagrams illustrating the setup and operation are also included. The document is intended to teach students about nontraditional machining as part of a manufacturing technology course.
Electric Discharge Machining (Modern Machining Process)Dinesh Panchal
Electric discharge machining (EDM) is a machining process that uses electrical discharges to remove material from a conductive workpiece. In EDM, a precision-controlled tool electrode is used instead of a cutting tool to remove material via short electrical pulses. This allows EDM to machine hard metals and alloys that cannot be easily machined through conventional methods. The process leaves no burrs and can machine complicated components. Modern EDM uses pulsed DC power supplies to control parameters like voltage, current, frequency, and duty cycle to control material removal rate and surface finish.
Electrical Discharge Machine is an advanced machining method which removes metal by a series of recurring electrical discharges betweenn an electrode and a conductive workpiece, submerged in a dielectric fluid.
Electric discharge machining is an electrothermal machining process that can machine hard conductive materials using electric sparks. It works by applying a potential difference between a tool electrode and workpiece submerged in a dielectric fluid, causing electric sparks that erode away material. Key factors that affect the process include the electric current, pulse duration and frequency, electrode and workpiece gap distance, and dielectric fluid. EDM enables precision machining of complex shapes without mechanical forces and is useful for brittle materials. Applications include drilling micro holes, cutting intricate cavities, and machining hard alloys like turbine blades.
Electric discharge machining (EDM) is a machining process that uses electrical sparks to erode metals. It works by maintaining a precise gap between an electrode tool and a metal workpiece submerged in a dielectric fluid. Repeated electrical sparks are generated to melt and vaporize small amounts of metal from both the tool and workpiece, allowing complex and hard-to-machine shapes to be produced. EDM can machine metals regardless of hardness and without mechanical force, giving it advantages over traditional machining methods for difficult-to-cut materials.
Electrochemical Machining (ECM) has established itself as one of the major alternatives to conventional methods of machining difficult - to - cut materials of and generating complex contours, without inducing residual stress and tool wear.
This seminar is devoted to the study of influences of variable ECM parameters like applied voltage and feed rate keeping other parameters constant on the surface roughness (Ra) using Response Surface Methodology (RSM).
1. Wire electrical discharge machining (WEDM) is a non-conventional thermo-electric process that removes material from a workpiece using a series of electrical sparks between a wire electrode and the workpiece submerged in dielectric fluid.
2. Many factors influence the WEDM process, including wire positioning, flushing pressure, and material properties. Mathematical models are used to understand relationships between process parameters like peak current and duty factor, and performance measures like material removal rate.
3. Experiments are conducted to determine the effects of process parameters like pulse on/off time and servo voltage on material removal rate and surface roughness when machining H13 hot die steel. The optimal settings are identified using statistical techniques
Electro Discharge Machining
Introduction
Process
Process Parameters
Dielectric
Advantages of EDM
APPLICATIONS
Power generator
Wire EDM
ELECTRIC DISCHARGE GRINDING (EDG)
This document discusses electrical discharge machining (EDM) and wire cut EDM. It begins with a brief history of EDM and an overview of the EDM process, including its working principle, important characteristics, and applications. It then focuses on wire cut EDM, explaining its working principle, major components of the process, advantages, and disadvantages. The document concludes by outlining the scope and plan for investigating the effects of process parameters on material removal rate, surface finish, and kerf width in wire cut EDM.
Electrochemical machining (ECM) is a process that removes material from a conductive workpiece using electrical current. In ECM, the workpiece acts as an anode in an electrolyte bath, and material is removed from the workpiece and transported to a cathode tool. ECM can machine complex shapes in a single pass with no cutting forces and leaves the workpiece stress-free. Key factors that affect the ECM process include electrolyte composition and flow, voltage, feed rate, and current density between the tool and workpiece. ECM is used for aerospace, medical, and automotive applications where other machining methods cannot produce the required geometry or precision.
Electric discharge machining (EDM) involves removing material from a workpiece using electrical discharges between two electrodes separated by a dielectric liquid. It was invented in the 1940s by Russian physicists and can machine hard metals and intricate shapes that other methods cannot. The document discusses the history, working principle, material removal mechanism, advantages, and applications of EDM. It also covers technical parameters like electrode materials, dielectric fluids, and process variables that influence the material removal rate.
ELETROCHEMICAL MACHINING BY HIMANSHU VAIDHimanshu Vaid
Electrochemical machining (ECM) is an electrolytic process that removes material from a conductive workpiece acting as an anode using a tool acting as a cathode. Material is dissolved from the workpiece and flows away with the electrolyte. ECM can machine hard materials and complex shapes without thermal or mechanical stresses. It provides better surface finishes than conventional machining and EDM. Micro ECM uses smaller gaps and feature sizes for micromachining. Variations include electrochemical jet etching and laser-assisted jet etching for maskless patterning of thin films. The scanning electrochemical microscope also uses electrochemical reactions for high-resolution imaging and local etching.
Electrical discharge machining (EDM) is a non-traditional machining process that uses electrical sparks to remove metal. The document discusses the history and development of EDM, including key components like the electrode, workpiece, dielectric fluid, and power supply. It describes the basic EDM process and different EDM methods like conventional EDM, wire EDM, and hole drilling EDM. The document also covers EDM applications, innovations like dry EDM and powder-mixed EDM, and concludes with a list of references.
The document summarizes electrodischarge machining (EDM). EDM uses electrical sparks to erode material from a workpiece and tool electrode separated by a dielectric liquid. Key points:
- Material is removed through high-temperature melting and evaporation caused by electrical discharges between the electrodes.
- Process advantages include ability to machine hard materials and produce complex geometries without mechanical forces.
- Factors like pulse characteristics, electrode material properties, dielectric properties influence material removal rate and surface finish.
- EDM leaves a recast layer and heat-affected zone in the workpiece due to high temperatures from sparking.
This document summarizes the various departments and activities of the Gulzar Exploration and Transformation Tank (GETT) research center. It includes departments for faculty and student research, industry-academia collaboration, instrumentation facilities, intellectual property services, entrepreneurship incubation, and more. GETT focuses its research efforts on areas like agritech, healthtech, edutech, and next generation materials. It also lists major research projects and funding received. The document outlines GETT's policies and programs to support innovation, research, and commercialization through incentives, funding, infrastructure, and entrepreneurship resources.
This document provides information about a differential gear including:
1. It lists 4 student names who are presenting on the topic.
2. It describes the main parts of a differential gear including the pinion drive gear, ring gear, differential case assembly, rear drive axles, rear axle bearings, and axle housing.
3. It explains the power flow through a differential gear starting from the drive shaft spinning the pinion gear which turns the ring gear and differential case to spin the sun gears and axles to transfer power to the wheels.
This document provides an overview of metal casting processes. It discusses the history of casting, why casting is used, basic casting terms and steps in the casting process. The basic casting process involves making a pattern, using the pattern to form a mold cavity, melting metal, pouring the molten metal into the mold, allowing it to cool and solidify, and then cleaning the final casting. Key terms discussed include molds, cores, gating systems, and allowances provided in patterns.
The document provides an overview of metal casting processes and concepts. It discusses the basic steps of casting including heating the metal, pouring it into a mold, and allowing it to solidify. Key aspects covered include mold materials and types, solidification of pure metals and alloys, shrinkage and directional solidification, and riser design. Chvorinov's rule relating solidification time to part geometry is also explained.
This document discusses the metallurgy of welding and weld design and process selection. It covers topics such as the distinct zones in a welded joint, the grain structure and solidification of weld metal, and discontinuities like porosity, slag inclusions, and cracks. It also addresses weld quality testing methods, both destructive and non-destructive, and the factors to consider in weld design and selecting the appropriate welding process, such as the component configuration, loading stresses, accessibility, and costs.
Electrochemical machining (ECM) is a non-traditional machining process that uses electrical current between an electrolyte tool and a conductive workpiece to remove metal atoms. It can machine complex cavities in hard materials with a burr-free surface finish. The process involves an electrolyte flowing between the tool and workpiece where an electrical current ionizes metal atoms from the workpiece. ECM can machine materials regardless of their strength or hardness and leaves no heat affected zone. It is commonly used for duplicating complex parts and machining difficult-to-cut materials like turbine blades.
Wire electrical discharge machining (EDM) is a non-traditional machining process that uses electricity to cut any conductive material precisely and accurately with a thin, electrically charged copper or brass wire as an electrode. During the wire EDM process, the wire carries one side of an electrical charge and the workpiece carries the other side of the charge. When the wire gets close to the part, the attraction of electrical charges creates a controlled spark, melting and vaporizing microscopic particles of material. Plasma arc cutting (PAC) uses a plasma torch to direct a high-velocity jet of hot plasma from an ionized gas to cut electrically conductive materials. PAC systems operate on either a non-transferred arc mode or transferred arc
This document discusses several non-traditional manufacturing processes including chemical machining, electrochemical machining, electro-discharge machining, laser cutting, ultrasonic machining, and water-jet machining. It provides details on the mechanisms and main applications of each process. Chemical machining uses chemical reactions to etch materials. Electrochemical machining is the reverse of electroplating and is used for dies, molds, and complex holes. Electro-discharge machining uses sparks to precisely cut conductive materials. Laser cutting uses a focused laser beam to cut and drill holes. Ultrasonic machining vibrates a tool with abrasives to machine brittle materials. Water-jet machining uses a high pressure water
Water jet machining uses a high pressure jet of water, or water with an abrasive additive, to cut materials. It can cut a variety of materials, including metals, paper, plastics and ceramics. The machining system includes a hydraulic pump to pressurize the water, an intensifier to further pressurize it, a mixing chamber and abrasive feed system for abrasive jet machining, and a cutting nozzle. Key advantages are that it produces no heat, requires little fixturing, and leaves a finished surface with little burr or heat-affected zone.
A lathe is a machine tool that is used to remove material from a rotating workpiece to produce cylindrical objects. It works by holding the workpiece firmly and rotating it at high speeds while a cutting tool is fed into the workpiece removing material to create the desired shape or features. Major components of a lathe include the bed, headstock, tailstock, carriage assembly, and main drive. Common lathe operations are turning, facing, knurling, taper turning, thread cutting, and drilling.
The document discusses additive manufacturing (AM) concepts and applications. It provides an overview of AM processes, including fused deposition modeling and selective laser sintering. Applications of AM include rapid prototyping to reduce product development time, generating prototypes for design reviews, and creating production tooling. The document also covers common AM terminology and the basic steps of the AM process from CAD file preparation to layer-by-layer part fabrication.
The document summarizes milling machine operations and accessories. It discusses that milling machines remove metal using revolving cutting tools called milling cutters. It can be used for boring, slotting, circular milling, dividing, and drilling. Milling machines are classified as horizontal or vertical based on spindle axis and as knee-type, ram-type, manufacturing, bed-type or planer-type. Common accessories include arbors to mount cutters, vises to secure workpieces, and indexing mechanisms to precisely rotate the workpiece.
This document discusses traditional manufacturing processes including casting, forming, sheet metal processing, cutting, joining, powder processing, plastics processing, and surface treatment. It provides details on specific cutting processes like sawing, shaping, broaching, drilling, grinding, turning, and milling. It also covers topics like fixturing, tool wear analysis, modeling of cutting mechanics and parameters, and optimizing processes for factors like production rate and cost.
The document discusses process planning and engineering. It describes the need to understand process capabilities at different levels including universal, shop, and machine levels. Process capabilities refer to the geometry, tolerances, material removal rates, and costs that manufacturing processes can produce. Decision tables and trees are presented as ways to represent process knowledge and rules for computerized process planning. Specific capabilities of processes like milling, drilling, turning, and grinding are also outlined.
Surface coatings can be used to prevent device-related infections by minimizing protein adsorption and binding. There are several methods for applying surface coatings including plasma treatment, adsorption, and covalent immobilization. Plasma treatment uses a reactive gas plasma to modify the surface chemistry without changing the bulk properties. Common gases used include oxygen, argon and air. Surface coatings can increase the surface energy and make materials more hydrophilic, reducing protein binding and cell attachment to help prevent infections. Emerging applications of surface coatings include coatings for enhanced imaging, drug delivery, and tissue engineering.
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2. PROCESS PRINCIPLES
• Electrical discharge machining (EDM) is a thermal
process that uses spark discharges to erode electrically
conductive materials.
• A shaped electrode defines the area in which spark
erosion will occur, thus determining the shape of the
resulting cavity or hole in the workpiece.
4. 4
• Electrical discharge machining is a relatively simple
manufacturing process to set up and perform.
• The electrically conductive workpiece is positioned in
the EDM machine and connected to one pole of a
pulsed power supply.
• An electrically conductive electrode, shaped to match
the dimensions of the desired cavity or hole, is
connected to the remaining pole of the power supply.
5. 5
• The electrode and workpiece are then positioned
in such a way that a small gap is maintained
between the two.
• To provide a controlled amount of electrical
resistance in the gap, an insulating (dielectric)
fluid is flooded between the electrode and work-
piece.
7. 7
• As illustrated in the sequence of drawings in
the figure, when a pulse of DC electricity is
delivered to the electrode and the workpiece,
an intense electrical field is created at the
point where surface irregularities provide the
narrowest gap.
• As a result of this field, naturally occurring
microscopic contaminants suspended in the
dielectric fluid begin to migrate and
concentrate at the strongest point in this
field.
• Simultaneously, negatively charged
particles are emitted from the workpiece.
Together these contaminants and particles
result in the formation of a high-conductivity
bridge across the gap.
8. 8
• As the voltage between the electrode
and workpiece increases at the
beginning of the pulse, the temperature
of the material making up the conductive
bridge increases.
• A small portion of the dielectric fluid
and charged particles in conductive
bridge vaporizes and ionizes resulting in
the formation of a spark channel
between the two surfaces.
9. 9
• At approximately the midpoint of the
electrical pulse, the power supply decreases
the voltage delivered to the gap, but raises
the current.
• This has the effect of increasing both the
temperature and pressure in the spark
channel.
• The extremely high temperature of the spark
melts and vaporizes a small amount of
material from the surfaces of both the
electrode and the workpiece at the points of
spark contact. Fed by the gaseous by-
products of vaporization, a bubble rapidly
expands outward from the spark channel.
10. 10
• When the electrical pulse is terminated, the spark
and heating action are stopped instantly.
• This causes both the spark channel and,
consequently, the vapor bubble to collapse.
• Small, rapidly solidified balls of material and gas
bubbles represent the residue from the cycle.
• The dielectric fluid acts to remove these by-
products from the gap.
• This entire sequence takes place in a period of only
microseconds to milliseconds.
12. 12
• D.C. Power Supply
• Frequency Control
• Work pan
• Servo Controlled Feed Workpiece
• Pressure Guage
• Flow meter
13. 13
Power Supply
• It transforms the alternating current (AC)
from the main utility electrical supply into the
pulsed direct current (DC) required to
produce the spark discharges at the
machining gap.
• First, the input power is converted into
continuous DC power by conventional solid-
state rectifiers.
• A small percentage of this DC power is used
to generate a square wave signal via a digital
multi-vibrator oscillator circuit.
14. 14
Dielectric System
• The EDM dielectric system consists of
the dielectric fluid, delivery devices,
pumps, and filters
• Various fluids are able to provide the
requisite properties of high degree of
fluidity and high electrical resistance.
• The most popular fluids, in order of
popularity, are transformer oil, paraffin
oil, kerosene, lubricating oils
hydrocarbon oil, silicon-based oils, and
de-ionized water.
15. 15
• De-ionized water is rarely used
because, although it results in high
material removal rates and increased
cooling capacity, it also results in
undesirably high electrode wear rates.
• Therefore de-ionized water is most
often used when drilling small diameter
holes while using wire as the electrode.
16. 16
Regardless of the fluid being used, three
functions are performed by the dielectric
fluid.
1. It acts as an insulator between the electrode
and workpiece,
2. As a coolant to draw away the small amount
of heat generated by the sparks,
3. And as a flushing medium to remove the
metal by-products from the cutting gap.
17. 17
High di electric sterngth to minimize DC arcing.
No toxic gases should be formed during ionization.
Odourless and easily available
18. 18
• Of the three dielectric fluid functions,
flushing is by far the most critical for
optimum process efficiency.
• Poor flushing results in stagnation of the
dielectric fluid and a buildup of tiny
machining residue particles in the gap.
• Stagnation usually results in low material
removal rates or short circuits.
20. 20
• Any of these flushing techniques can be
performed exactly as illustrated in Figure, or
with the work piece submerged in a tank of
dielectric fluid.
• Whenever inflammable dielectric liquids are
being used, submersion of the work piece is
recommended to reduce the chances of
accidental dielectric fluid fires.
• Because it is more cost effective to reuse the
dielectric, it is usually cleaned, recycled, and
returned to the cutting gap. Pumps and
disposable filters perform this function.
21. 21
PROCESS PARAMETERS
The selection of EDM parameters is
important in determining the accuracy
and surface finish obtained for a
particular application.
22. 22
Spark frequency, current & surface finish
• As current is increased, each individual spark
removes a larger crater of metal from the work
piece. Although the net effect is an increase
in material removal rates, when holding all
other parameters constant it also has the
effect of increasing surface roughness.
• The same effect is also observed when spark
voltage is raised.
• Electrical discharge machining equipment is
available that is able to operate between 0.5
and 400 amp and with voltages ranging from
40 to 400 V DC.
23. 23
• Increasing spark frequency and holding all
other parameters constant, results in a
decrease in surface roughness.
• The frequency capability of EDM machines
ranges from a low of 180 Hz when performing
roughing cuts, to a high of several hundred
kilohertz when generating the fine finishes
required for finishing cuts.
24. 24
Spark gap
• The gap between the electrode and
workpiece is determined by the spark voltage
and current.
• Typical values for the gap range from 0.012
to 0.050 mm (0.0005 to 0.002 in.).
• The smaller the gap, the closer the accuracy
with a better finish and slower material
removal rate.
• As the gap decreases, efficient flushing
becomes difficult to achieve.
25. 25
• Increasing the pulse duration of the
sparks has the effect of increasing the
removal rate, increasing the surface
roughness, and decreasing the
electrode wear.
• The values of pulse duration available
with currently available EDM machines
range from a few microseconds to
several milliseconds.
27. 27
Advantages
• By this process, materials of any hardness can be
machined.
• No burrs are left in machined surface.
• Thin and fragile/brittle components can be machined
without distortion;
• Complex internal shapes can be machined
• Although the metal removal in this case is due to thermal
effects, there is no heat in the bulk of the material
28. 28
Disadvantages
• This process can only be employed in electrically
conductive materials;
• Material removal rate is low and the process overall is
slow compared to
• conventional machining processes;
• Unwanted erosion and over cutting of material can occur;
• Rough surface finish when at high rates of material
removal.
29. 29
APPLICATION
• Useful in machining of small holes, orifices,
slots in diesel fuel injection nozzles, airbrake
valves and aircraft engines etc.
• Blind cavities and narrow slots in dies, minimum
diameter hole can be produced.
• Mold making
33. Special form of EDM is wire EDM,
wherein the electrode is a continuously
moving conductive wire made from
copper, brass, tungsten or molybdenum.
(about 0.25mm in diameter).
The process is widely used for the
manufacture of punches, dies and stripper
plates.
34. 34
Wire electrical discharge machining (EDM) is a non-traditional machining process that
uses electricity to cut any conductive material precisely and accurately with a thin,
electrically charged copper or brass wire as an electrode.During the wire EDM process,
the wire carries one side of an electrical charge and the workpiece carries the other side
of the charge. When the wire gets close to the part, the attraction of electrical charges
creates a controlled spark, melting and vaporizing microscopic particles of material. The
spark also removes a miniscule chunk of the wire, so after the wire travels through the
workpiece one time, the machine discards the used wire and automatically advances
new wire. The process takes place quickly—hundreds of thousands of sparks per
second—but the wire never touches the workpiece. The spark erosion occurs along the
entire length of the wire adjacent to the workpiece, so the result is a part with an
excellent surface finish and no burrs regardless of how large or small the cut.Wire EDM
machines use a dielectric solution of deionized water to continuously cool and flush the
machining area while EDM is taking place. In many cases the entire part is submerged
in the dielectric fluid, while high-pressure upper and lower flushing nozzles clear out
microscopic debris from the surrounding area of the wire during the cutting process. The
fluid also acts as a non-conductive barrier, preventing the formation of electrically
conductive channels in the machining area. When the wire gets close to the part, the
intensity of the electric field overcomes the barrier and dielectric breakdown occurs,
allowing current to flow between the wire and the workpiece, resulting in an electrical
spark.
35. 35
On most wire EDM machines, the path of the wire is controlled by computer numerically-
controlled (CNC) diamond guides, which can move independently of each other on
multiple axes for tapered cuts and complex shapes such as small-radius inside corners
and narrow slots. Additionally, wire sizes vary from 0.012” diameter down to 0.004” for
high-precision work. Wire EDM is capable of holding tolerances as tight as +/-
0.0001”.Wire EDM provides a solution to the problems encountered when trying to
machine materials that are normally difficult to work with, such as hardened steel,
aerospace-grade titanium, high-alloy steel, tungsten carbide, Inconel, and even certain
conductive ceramics.
One requirement of the wire EDM process is a start hole for threading the wire if the
part’s features do not allow you to cut an edge. Wire EDM can only machine through
features; however, we can quickly drill a hole in any conductive material using another
type of EDM, small hole drilling or “hole pop” EDM.
38. 38
WORKING PRINCIPLE
• A gas molecule at room temperature consists of
two or more atoms. When such a gas is heated to a
high temperature of the order of 2000°C or so, the
molecules separate out as atoms.
• If the temperature is raised to 3000°C, the
electrons from some of the atoms dissociate and
the gas becomes ionized consisting of ions and
electrons. This state of gas is known as plasma.
41. 41
• Thus, plasma is the glowing, ionized gas that results
from heating of a material to extremely high
temperature.
• It is composed of free electrons dissociated from the
main gas atoms.
• A gas in plasma state becomes electrically
conductive as well as responsive to magnetism.
Because of such behavior, plasma is also known as
a fourth state of matter.
42. 42
• The temperature of plasma can be of the
order of 33,000°C.
• When such a high temperature source reacts with
work material, the work material melts out and
may even vaporize, and finally is cut into pieces.
• Many materials (say, aluminium, stainless steel,
etc) have high thermal conductivity, large heat
capacity, and/or good oxidation resistance. As a
result, such materials cannot be cut by
conventional techniques like oxy-fuel cutting.
• But these materials can be easily cut by plasma
arc cutting (PAC).
43. 43
PLASMA ARC CUTTING SYSTEM
• PAC system uses DC power source. PAC systems
operate either on non-transferred arc mode or
transferred arc mode (Fig. 9.1).
• In non-transferred arc mode, the thermal
efficiency is low (65-75%) and power is
transferred between the electrode and the nozzle.
This non-transferred arc ionizes a high velocity
gas that is streaming towards the work piece.
• The work piece may be electrically conductive or
non-conductive.
45. 45
• Fig. 9.1 Schematic diagram for non-transferred
and transferred arcs.
• In case of a transferred arc mode, the arc is
maintained between the electrode (negative
polarity) and the electrically conductive work
piece (positive polarity).
• Note that only electrically conductive work piece
can be machined or cut by transferred arc system.
The arc heats a co-axial flowing gas and maintains
it in a plasma state.
46. 46
• The electro thermal efficiency is up to 85-90%.
PAC system can deliver up to 1000 A at about 200
V (DC).
• The flowing gas pressure may be up to 1.4 MPa
resulting in a plasma velocity of several hundred
metres/second. Higher the gas flow rate, more will
be momentum of the plasma jet.
• It will ease out removal of the molten material
from the machining zone.
• The plasma jet is constricted by the flowing gas
which acts as a cooling agent sandwiched between
the nozzle wall and the plasma jet.
47. 47
• In case of PAC, the material may be removed
either by melting, or by melting and vaporization
both.
• In either case, the material (in molten state or
vaporized state) is blown off from the machining
zone by high velocity plasma jet.
48. 48
ELEMENTS OF PLASMA ARC CUTTING
SYSTEM
The important elements of a PAC system are
• Plasma torch.
• Power supply,
• Gas supply,
• Cooling water system,
• Control console
49. 49
Plasma torch
There are many torch designs which are practically
used, for example
air plasma
oxygen injected
dual gas
water injected plasma torch.
50. Air plasma torch
Air plasma torch uses compressed air as the gas that ionizes
and does cutting.
The air to be used should be uncontaminated.
The nozzle of this torch may result in prematured failure
because of double arcing i.e, arcing between the electrode
and the nozzle, and between the nozzle and the work piece.
Zirconium or hafnium are used as electrode material
because of their higher resistance to oxidation.
50
52. 52
Oxygen injected
• To avoid oxidation of electrode (or to enhance the life of the
electrode), oxygen injected torch (Fig. 9.3) uses nitrogen as the
plasma gas.
• Oxygen is injected downstream of the electrode. However, it
lowers down the nozzle life. This torch gives high MRR and
poor squareness of the cut edges. It is commonly used for mild
steel plate cutting.
• The presence of oxygen in the air helps in increasing MRR in
case of oxidizable materials like steel.
54. 54
Dual gas system
It uses one gas (nitrogen) as the plasma gas while another gas as
the shielding gas (02, C02, argon-hydrogen, etc). Secondary or
shielding gas is chosen according to the material to be cut.
Secondary gas system helps in maintaining sharp corners on the
top side of the cut edges.
56. 56
• To avoid double arcing, the lower part of the nozzle is made of
ceramic.
• Water constriction helps in reducing smoke, enhancing nozzle life,
reducing HAZ, and limiting formation of oxides on the cut edges of
the workpiece.
water injected torch
water (pressure =1.2 MPa) is injected (radially or swirling vertically)
to constrict the plasma. A small quantity (about 10%) of water
vaporizes. This thin layer of steam constricts the plasma and also
insulates the nozzle. Nitrogen at about 1 MPa is used as the plasma.
57. 57
• Water muffler (a device that produces a covering of water
around the plasma torch and extends down to the work
surface) helps in reducing smoke and noise.
• Water mixed with a dye also absorbs part of the ultraviolet
rays produced in PAC.
• In some cases, a water table is also used to reduce the level of
noise and extent of sparks. Water below the workpiece
quenches sparks and damps sound level.
• Underwater PAC systems are also available which effectively
reduce the noise and smoke levels.
59. Mechanism of metal removal
Heating of workpiece is as a result of anode heating, due to
the electron bombardment plus convection heating from
high temp plasma that accompanies the arc.
Approx 45% of electrical power delivered to torch is used
to remove metal from workpiece.
Arc heat is concentrated on a localized area of w.p and it
raised it to its melting pt.
59
60. PAM Parameters
• 1. Design of DC plasma torches:
• 2 Physical Configuration
• 3. Work Environment
60
61. Process Characteristics
• Cutting rates : 250-1700mm/min
• Accuracy on width of slot and diameter of holes is
ordinarily from
+_ 0.8mm on 6-30 mm thick plates and
+ _3.0 mm on 100-150mm thick plate.
• Depth of HAZ depends on work material, its thickness and
cutting speed.
61
62. 1. Gas for Plasma generation
Gas that does not attack tungsten electrodes or workpiece
can be used as plasma gas.
For cutting Carbon and alloy steels- a mixture of N and H
with compressed air.
For cutting stainless steel, aluminium and other non-ferrous
metals- mixtures of argon-hydrogen or N-H are used.
Typical gas flow rates are 2 to 10 m3/hr.
62
63. 2. Cutting Rates
250-1700 mm/min. which depends on thickness of metal
being cut.
Sometimes water is injected into the jet which helps in
confining the arc, in blasting away the scale and smoke
reduction.
Water injected plasma can increase cutting rate by 40–50%
A 5mm thick carbon steel plate can be cut at 6000mm/min.
63
64. • 3. Surface finish and accuracy:
It gives better accuracy than oxy- acetylene gas cutting. Cut
edges are round, with corner radius of about 4mm. There is
also problem of taper (about 2-5 degree).
cut width is around 2.5 to 8mm.
Accuracy + _ 0.8mm on 5 to 30mm plates
+_ 3.0mm on 100 to 150mm thick plates.
64
65. 65
Advantages of PAM
1. Plasma Arc Cutting produces a high
quality, dust free cutting.
2. Straight as well as curved shapes can
be cut easily.
3. The corrosion resistance of the
stainless steel is not effected when it
is cut with plasma arc.
4. The plasma arc cutting is the fastest
of all cutting processes.
66. 66
Disadvantages of PAM
1. It needs more electrical equipments;
hence chances of electrical hazards
are more.
2. The plasma arc produce a high noise.
The use of ear plugs or ear muffs to
protect the operator is essential.
3. The initial cost of process equipments
are very high.
67. 67
Safety Precautions
• Machine the heat affected zone
(0.75-5 mm).
• Regulate gas pressure (approx. 1-
1.4 MPa).
• Maintain constant distance between
torch and work piece.
• High labor safety (i.e. goggles,
gloves, etc…).
• Proper training for operators.
• Protection against glare, spatter and
noise from the plasma.
68. 68
Gases Used
Primary Gases:
Gases that are used to create the plasma arc.
Examples are nitrogen, argon, hydrogen,
hydrogen, or mixture of them
Secondary Gases or Water:
Surrounds the electric arc to aid in confining it
and removing the molten material.
70. 70
System Components
The torch is the
holder of the
consumable electrode
and nozzle.
Responsible for
forming the arc and
maintain it in a vortex.
A. The Torch:
Groover 626
71. 71
System Components
Constant DC current
source.
Speed and cut
thickness are
determine by the
amount of output
current.
B. Power Supply:
72. 72
High frequency
generator circuit that
produces a high AC
Current.
To start the arc, the AC
current ionizes the
cutting gas, which
makes it conductive to
allow the DC current to
flow through it.
System Components
C. Arc Starting Circuit:
73. 73
Advantages - Disadvantages
• Cuts any metal.
• 5 to 10 times faster
than oxy-fuel.
• 150 mm thickness
ability.
• Easy to automate.
• Large heat affected
zone.
• Rough Surfaces
• Difficult to produce
sharp corners.
• Smoke and noise.
• Burr often results.
75. 75
Other Plasma Uses
• Plasma Arc Welding (PAW)- plasma arc is
produced and aimed at the weld area to weld.
• Applications- Used for butt and lap joints
because of higher energy concentrations and
better arc stability.