This method involves cutting metals and even non-metals using water streams with pressures approaching 50,000 to 60,000 PSI. Newer waterjet systems are capable of pressures up to 90,000 PSI. These high pressures can cut almost any material. This high-pressure water stream is used to cut a narrow line between the materials used.For harder materials, add impurities or granular abrasives to the water stream to cut them. This is called the abrasive water jet cutting method. This material helps to erode materials that are difficult to cut with a simple stream of water.Must Read: Abrasives vs Pure Water Jet CuttingThe water jet cutting method is widely used in the industry due to its ability to cope with changes. The accuracy of this method can be improved by increasing the pressure of the flow. It can also be achieved by adding a nozzle to the output. This helps improve the machine's results.
Micro water jet cutting is an advanced method of cutting materials at the microscopic level. This method uses a smaller nozzle diameter, resulting in more precise and smaller cuts.
Another technique used to cut more complex parts is called 3D water jet cutting. This method involves moving the head to apply a flow of pressure to the material. Cuts can be made in three dimensions, which helps produce 3D parts instead of flat material cuts.
CNC water jets make it easier for operators to get to the end result and increase productivity. These methods are known to take time to complete, so the CNC method offers a lot of convenience for the owner.
Now let's look at some of the features of waterjet cutting.
This method produces an accuracy of almost ±0.003". Greater accuracy can be achieved by using advanced software in operating the machine. A better operating system can produce better results.
The water jet cutter is capable of cutting parts up to 3 inches thick. Thicker parts can be cut with less precision or speed.
The average cutting speed of a nominal waterjet cutter is known to be around 760 m/s. The high pressure water flow makes the process very fast and less time consuming.
Heat Affected Zone (HAZ):
This method has almost no HAZ because it uses pure water and has no heating elements. This helps to improve the quality of the product.
When using the water jet cutting method, the quality of the product edges proved to be good.
This method does not distort the material or alter any properties of the material used.
EDM is a more precise and accurate method of cutting conductive materials. It uses a series of sparks to cut metal and other conductive materials. The basic EDM process involves sparking between an electrode and a conductive workpiece. The spark then erodes the material, making way for the cut. This discharge generates heat of around 8000-12000 degrees. An advanced technique for EDM is the use of wire-cut material. The wires are live and close to the material. The electrical current in the wires creates sparks and the material makes way for the wires. In this way, the wire moves along a defined path and through the material. The wire cutting method proved to be more accurate than basic EDM cutting. Wire provides good precision when cutting. There are two main ways to wire EDM materials. They are single cut and skim. The one-cut method means that the wire will only go through the material once, which will cause some of the wire to fall off or remain on the edge of the material. This results in rough edges of the product. In most cases, skimming is required to smooth the final product as desired. The Skim-Cut method involves multiple turns of wire going through the same path, making the cut smoother than before. The minimum number of rounds in this method is two. However, as the number of rounds increases, so does the smoothness of the surface. It is said that there are up to 9 rounds of skim cutting.
Let's look at some basic features of this method.
Wire EDM is more accurate, with an accuracy of ±0.0001". Wire used to corrode materials is used for accuracy purposes.
In the case of EDM cutting, parts can be up to 12 inches thick. The length of the wire can be increased to achieve thicker cuts, but the precision must be reduced for this.
The average cutting speed of the EDM cutter is 18"-20"/hour. This speed is set for normal EDM cutters.
Heat Affected Zone (HAZ):
The process uses an electrical discharge to generate high temperatures for cutting. Therefore, some degree of HAZ will be present in the processed material.
When using this process, the quality of the cut edges has proven to be excellent. After the process is complete, the material becomes a very fine product.
The sole purpose of this process is to cut by melting the material. This causes thermal deformation of the material and changes the properties of the material to some extent. But the deformation is negligible as it does not affect the appearance and durability of the material.
Waterjet VS EDM Cutting: Which is Better?
A waterjet cutting machine can be considered seemingly fast as compared to the EDM cutting machines. The waterjet machine provides more pieces/hour than the EDM machine.
Both machines are well known for their accuracies, but EDM machines win in case higher accuracy is required. The waterjet method can be considered only when the tolerances are not extreme.
On the other hand, the benefits of water jet cutting are incredibly great as it can cut almost any material., whereas the EDM machine is specifically required to cut through only conductive materials.
The waterjet cutting method is widely used in the industry as it is extremely fast, and there is room for improvement. The EDM method is said to have no room for such improvements, and accuracy cannot be increased by making any changes.
The advantages and disadvantages of the two methods discussed indicate clearly that for mass production of cut parts or if the product needs to be produced at a higher rate, the Waterjet method is proven to be more successful than the EDM cutting method. The Waterjet cutting method can be a bit expensive as it requires more maintenance and supervision than the EDM Cutting machines, but their success in the industry shows us how efficient a waterjet cutting machine is.
So if any industry is looking for cutting machines, the waterjet cutting machine is the best option to opt for. This will yield better and faster production than any other method.