What is the Spark Erosion Process?

Imagine you’re on the production line working on a large manufacturing machine. Everything seems to be running smoothly, until crack, a tap has broken off in the machine. A person breaks the tap, not the machine.

Unable to retrieve the broken piece without damaging the machine or stripping the threads of the casting, you are left with two options. You can replace the broken machinery, which comes at a high cost and slows productivity, or you can apply spark erosion, solving your problem in seconds rather than hours or days and for a quarter of the cost.

Spark erosion, metal disintegration, electrical discharge machining; if you work in any industry that utilizes machinery you’ve probably heard one or more of these terms. Each of these titles is used to explain the process of removing metal using electric currents under carefully controlled conditions.

How does the spark erosion process work?

While (EDM) spark erosion can be used to create specific metal parts, it is also commonly used to remove broken drill bits, taps, bolts, and studs from within a machine casting without damaging the threads or casting itself. This is called MDM.

Spark erosion is conducted through metal disintegration machines (EDM). These machines use electrodes to send low voltage/ high current electrical charges that melts the designated piece of metal at the same time cold water thermal shocks the molten steel and pulverizes it into micro-size pieces and flushes it away.

Because there is no direct contact between the electrodes and the machine casting, spark erosion allows you to work with even the most intricate sections and weak materials without risking distortion. It is this precision that makes spark erosion the most effective way to salvage parts that would otherwise be deemed unusable.

Five steps to applying spark erosion

Step 1: Get your metal disintegration machine ready. Electro Arc has a variety of options to choose from depending on your need, including portable, table top, and specialized metal disintegrators.  Use our new Machine Builder if you are not sure which machine is best for your application.

Step 2: If you are using a portable machine, attach the provided portable electrode head to your drill press, CNC machine, lath, or any type of machine tool.

Step 3: Align the electrode to ensure it’s centered over the object you plan to remove and lower the splash bag.  Verify that the bolts are tight. Each machine comes with a splashguard mechanism for safety purposes in order to keep sparks contained and prevent eroded metal from flying.

Step 4: Switch on the power supply. Portable metal disintegrators come with a small, rolling power supply cabinet that is easily transportable. The power supply features a built-in coolant tank and heat selector knob. For easy usability, all machines come with a chart that directs you on exactly which heat setting to use for each size broken tap or drill that you’re planning to remove.

Step 5: Turn the heat selector knob to the desired temperature and begin the process. Within seconds, the MDM machine will finish its cut. You can then clear the hole of any remaining debris using the provided air compression tool and see that your part has been completely recovered, casting, and threads left unscathed.

Yo can see the Electro Arc process in action, with video tutorials and case studies on Electro Arc’s YouTube Channel.  Since Stillion Industries purchased Electro Arc in 2019, we have created a new channel with updated videos as well.

Advantages of using spark erosion machines

In a previous blog post, we discussed the many benefits of using Electro Arc’s spark erosion machines, some of which include:

•      Simple operation
•      Unbeatable price
•      Relatively lightweight and easy to maneuver
•      Quick setup and breakdown
•      Easily manageable for one person
•      Little-to-no maintenance; simply keep it filled with fresh coolant

Spark erosion is the fastest and most cost-effective solution to recovering machinery that has been compromised by broken tools. For 75 years, Electro Arc has been perfecting this process and supplying premium metal disintegrators at affordable prices throughout the world.

You can see lots of broken bolt removal examples which illustrate how an Electro Arc metal disintegrator will benefit your company and save you money.