What is the tolerance for EDM?
Using a wire EDM, we can hold tolerances as tight as ±0.0001” on parts up to 12” in length, 10” in width, and 8” in height. As a result of its ability to cut fine part features in hardened alloys, EDM is a natural choice in the machining of fixtures, inspection gauges, and other profile or contour work.
What are the advantages of wire EDM over conventional EDM?
A: Wire EDM can produce patterns and shapes previously unachievable using conventional tools. Hard materials do not affect wire EDM’s cutting rate or ability to create complex geometric shapes. Wire EDM is not used if the raw material selected is not electrically conductive.7 Feb 2022
Is EDM machining expensive?
EDM wire, at its current cost of approximately $6 a pound, is the single highest cost related to the use of WEDM technology. The faster a machine unspools wire, the more it costs to operate that machine.
What are the factors on which MRR in EDM depend?
The MRR greatly depends on the process parameters. A higher value of discharging voltage, peak current, pulse duration, duty cycle, and lower values of pulse interval can result in higher MRR.
What are the components of EDM?
EDM system consists of four basic components tool electrode and work piece, pulsed power supply system, dielectric supply system and electrode feeding system which are shown in Fig.
What is the purpose of wire cut EDM machine?
Wire EDM machine uses a metallic wire (electrode) to cut a programmed contour in a workpiece. Extrusion dies and blanking punches are very often machined by wire cutting. In the machining area, each discharge creates a crater in the workpiece (material removal) and an impact on the tool (wear of the tool/electrode).
What material Cannot be cut using EDM wire cut?
Due to the nature of wire EDM cutting — removing material by using rapidly repeating, controlled electrical charges along a strand of metal wire — the method is limited to electrically conductive materials. Therefore, any material that is a composite or coated with a dielectric is not feasible for EDM.
How thick can EDM cut?
For example, EDM not only can cut a precious metal wire of 0.004″ (0.1 mm) diameter to a length of 1″ (25 mm), but also can do so while achieving a length tolerance of ±0.001″, radiused ends, and a Ppk well over the standard minimum of 1.33.29 Mar 2018
How accurate is EDM machining?
Accuracy and Tolerances Wire EDM is extremely accurate. Many machines move in increments of 40 millionths of an inch (. 00004″) (. 001 mm), some in 10 millionths of an inch (.
How is wire EDM time calculated?
To calculate the time, take the periphery of the part, one time around, divided by the A.L.F. (Average Linear Feed Rate) value shown for the last pass of the cut you will be taking.18 Sept 2015
What are the work parameters for EDM?
The important process parameters that have been selected are peak current, pulse on time, die electric pressure and tool diameter. The outputs responses are material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR).
How accurate is wire EDM?
While accuracies of +/- 0.00004” (0.001mm) are sometimes quoted for wire EDM, +/- 0.0002” (0.005mm) is more widely accepted. The reality is that EDM accuracy depends on a combination of workpiece characteristics, the surface finish desired, and the time available for machining.
How fast is EDM machining?
EDM units from the early 1980s might achieve cutting speeds of 3-4 square inches per hour. With changes in machine design and power supplies, speeds of 17 square inches per hour became attainable in the 1990s.
Which one of the following is most important parameter for EDM?
1. Which one among the following, is the most important factor in determining the tool wear? Explanation: In EDM, melting point is the most important factor in determining the tool wear.
How long does EDM machining take?
Some small-hole drilling EDMs are able to drill through 100 mm of soft or hardened steel in less than 10 seconds, averaging 50% to 80% wear rate.
How thick is a EDM wire?
Standard EDM wire is 0.25mm in diameter. Microwires can range from 0.15mm down to 0.020mm.
What is the spark gap range of EDM?
The lightning spark occurs at very long distances from the cloud to the ground, and the voltage reaches millions volts. In EDM, the voltage supplied is approximately 50 to 300 volts because higher voltage is not suitable for high precision machining. Therefore, EDM discharge gap is about 0.005 – 1.0mm.
How thin can wire EDM cut?
How is MRR calculated in wire EDM?
The material removal rate (MRR) for Wire cut EDM is calculated by using the equation(1), MRR = F×Dw×H (1) Where, F is the machine feed rate (mm/min), Dwis wire diameter (mm), H is the thickness of the workpiece (mm).
What is advantage of using EDM?
Advantages of Electrical Discharge Machining Suits very small work pieces, where conventional cutting tools may damage the part from excess cutting tool pressure. There is no direct contact between tool and work piece. Therefore, delicate sections and weak materials can be machined without any distortion. No burrs.
What is wire EDM used for?
Wire EDM is most commonly used in mold and die manufacturing processes, particularly for extrusion dies and blanking punches. EDM can be used in everything from prototypes to full production runs, and is most often used to manufacture metal components and tools.