Waterjet cutting has undoubtedly revolutionised the manufacturing industry with its ability to cut a wide range of materials precisely. It allows you to cut everything from metal to glass accurately. What is waterjet cutting, you may be wondering?
Simply put, it’s a manufacturing process that uses a high-pressure stream of water, or a mixture of water and an abrasive substance, to cut a wide variety of materials.
Whether you’re just looking to understand the basics or want to expand your knowledge, you’ll find in this guide all the information you need about waterjet cutting. We’ll explore the process of waterjet cutting by going through all the materials it can cut, how beneficial it is, and its application across different industries. So, let’s get into it!
What is a Waterjet Cutter?
Before explaining what waterjet cutting is as a process, let’s start by answering the key question related to waterjet cutters – What is a waterjet cutting machine? We’re talking about a sophisticated machine that uses a high-pressure stream of water or a mixture of water and an abrasive substance, such as a garnet, to cut through various materials. Manufacturers often prefer this cutting method over traditional ones because of its precision.
It consists of three parts: the table, a high-pressure pump, and the controller. The table provides support for the material being cut, while the pump generates the powerful water pressure. With dedicated software, you can operate this process via the controller, which directs the high water pressure emanating from the cutting head, thus ensuring precise and accurate cuts.
What is Waterjet Cutting?
Waterjet cutting is a CNC manufacturing process that’s both precise and versatile. It uses a high-pressure stream of either pure water or water combined with abrasive media in a mixing chamber. The former is mostly used for softer materials, while abrasive mixtures turn waterjet cutters into very powerful tools that can go through hard surfaces like metal or stone.
The history of waterjet cutting technology dates back to the 1950s. It was initially used for mining operations, but as the years passed, it was used sparingly until abrasives to the water stream were introduced in the 1970s. Its commercial use started in industries where precision was critical, such as aerospace and automotive, and over time, the technology became even more precise, faster, and easier to use.
Today, many prefer waterjet cutting, regardless of the field, mostly due to its ability to maintain the integrity of various materials while delivering precise cuts without heat distortion.
The Steps of The Waterjet Cutting Process
So, how does a waterjet cutter work? The water jet cutting process involves several steps:
- It begins with material preparation, where the material is securely fixed to the cutting table to maintain stability and allow for precision during cutting.
- Next, a high-pressure water stream is generated using a specialized pump system.
- The pressurized water then goes through a nozzle and high-pressure tubing, narrowing and focusing the stream into a high-velocity jet.
The focused waterjet (or abrasive waterjet) stream is then directed toward the material. It effectively cuts through it. Control over the movement of the nozzle determines the shape and depth of the cut, which is in the hands of the person operating the machine.
Once the cutting process is complete, you must perform a quality check to ensure that the cut meets the required specifications. In cases of abrasive waterjet machining, abrasive particles can be introduced into the water stream at the nozzle, enhancing the cutting capabilities.
Types of Waterjet Cutting Machines
The two main types of waterjet cutting machines are pure waterjet cutters and abrasive waterjet cutters. So, what is the difference between water jet machining and abrasive water jet machining? They both operate on the same underlying principles, but there are a few differences you need to be aware of:
| Methodology | Materials | Cutting Applications | Industries | |
| Pure Water Jet Cutting | A high-pressure stream of water only. | Foam, rubber, or certain types of plastics. | Packaging, insulation, or gasket manufacturing. | Aerospace, automotive, medical. |
| Abrasive Water Jet Cutting | A high-pressure stream of a mixture of an abrasive substance, typically garnet, with water. | Metals, ceramics, stone, or composites. | Cut parts and complex shapes in stone, glass, and composite materials. | Architecture, construction, and manufacturing. |
How Does Water Jet Cutting Work?
As already mentioned, waterjet cutting forces a high-pressure stream of water or a mixture of water and abrasive through a small nozzle. So, how strong is a water jet cutter? Well, the pressure can range from 30,000 to 90,000 pounds per square inch (psi), depending on the material and the cutting speed.
Since waterjet cutters are supersonic, the stream of water (or water-abrasive jets) exits the nozzle at an extremely high velocity. This typically exceeds the speed of sound. As the water or water-abrasive mixture makes contact with the material being cut, it erodes the material and creates a narrow kerf.
The kinetic energy of the jet is responsible for the cutting action. Every time you add an abrasive substance, such as garnet, it enhances the cutting ability of the water jet. The abrasive particles act like tiny projectiles. They erode the material effectively and produce a clean and precise cut.
Applications of Waterjet Cutting
So, what is waterjet cutting used for? Due to its versatility and ability to cut a wide range of materials, it’s used in many industries. In the aerospace industry, for example, people use it to fabricate intricate components, such as turbine blades or aircraft panels.
In the automotive industry, they use waterjet cutting for cutting gaskets, interior components, or even body panels. Its ability to achieve high levels of precision and to cut complex shapes makes waterjet cutting a particularly valuable tool in automotive manufacturing.
Waterjet cutting is also used in the food processing industry for cutting fruits, vegetables, and meat products. The cold-cutting process of waterjet cutting ensures the integrity of the food products, eliminating the risk of heat-related damage or contamination.
Benefits of Using Waterjet Machining
Waterjet machining has gained significant popularity due to its unique and advantageous characteristics. The benefits of waterjet cutting make it not only superior when compared to other, more traditional methods of cutting but also more environmentally friendly.
Enhanced Edge Quality
One of its advantages is the enhanced edge quality it delivers. The waterjet cutting process minimizes the formation of heat-affected zones (HAZ), resulting in smooth, burr-free cut edges that require minimal additional finishing. Since there’s no heat involved in the process, it ensures that the material’s properties remain intact, making it perfect for heat-sensitive materials.
Cost Savings
Another significant benefit is cost savings. It was historically one of the most costly 2D machining methods, but as technology advanced, it became more affordable. Fast, automated processes contribute to cost savings in every part produced with the process.
Waterjet cutting also minimizes material wastage due to its narrow kerf width. Its precision ensures minimal material loss, thus impacting overall costs associated with material waste.
Improved Efficiency
Waterjet machining allows high-speed cutting without compromising accuracy and precision. The controlled movement of the nozzle, along with the narrow kerf width, ensures efficient material use. Efficiency improves further with the ability of waterjet cutters to accommodate materials of various thickness levels. It can cut through high-thickness materials with significantly reduced internal stresses, making it super efficient in producing complex designs..
Accurate Internal Cuts
One of its best capabilities is to produce accurate internal cuts, even with very complex geometry. The precision and flexibility of the water jet stream allow for intricate cuts and designs, making it suitable for a wide range of applications in this context. This is especially beneficial in the aerospace, automotive, and electronics industries.
Reduced Restraints on Material Thickness
Waterjet cutting offers reduced restraints on material thickness compared to other cutting methods. In many cutting processes, the thickness of the material can pose a challenge and limit the effectiveness of the cut. With waterjet cutting, however, these limitations are reduced.
How thick can a waterjet cut? Well, it can cut materials of a very wide range of thickness levels without compromising the quality or effectiveness of the cut. On top of that, waterjet cutting’s cold-cutting process reduces internal stresses on the material, making it a great option for heat-sensitive materials.
Environmentally Friendly
It doesn’t produce any harmful emissions or waste, as it doesn’t involve any chemical reactions, combustion, or melting of the material. The only by-products are water and the removed material, which can be recycled or disposed of safely.
Waterjet cutting uses far less water and energy than other cutting methods, as it recycles the water used in the cutting process and only requires a small amount of abrasive material.
Materials Suitable for Waterjet Cutting
Have you ever wondered what materials a waterjet can cut? It’s suitable for a wide range of materials, including metals, plastics, composites, foam, rubber, and glass. Given the different compositions of materials and the different types of waterjet cutters, each material has its characteristics and considerations to take into account for waterjet cutting.
- Metals. Waterjet cutting is highly effective for cutting metals such as steel, aluminium, and titanium mainly because of its cold-cutting process. It can also cut through extreme thicknesses, regardless of the type of metal.
- Plastics. Plastics, including acrylic, polycarbonate, and PVC, are easily cut with water jet machining. The absence of heat during the cutting process minimizes the risk of melting or warping, ensuring clean and precise cuts.
- Composites. Composite materials, such as carbon fiber and fiberglass, benefit from waterjet cutting due to its precision and minimal delamination.
- Foam and Rubbers. Waterjet cutters can cut soft materials with extreme efficiency, like, for example, foam and rubber materials. This is why the method is increasingly used in industries such as packaging, automotive, and insulation.
- Glass. Delicate and brittle glass requires a cutting method that eliminates thermal stress. Waterjet machining easily achieves this, providing precise glass cutting without cracking or chipping.
Water Jet Cutting Vs Traditional Cutting Methods
Water jet cutting is versatile, eco-friendly, and precise, but how does it compare to traditional methods of cutting, such as plasma, laser, or mechanical cutting? There are several advantages that waterjet cutting offers over traditional cutting methods, making it a popular choice in the manufacturing industry.
A big one is the absence of heat-affected zones (HAZ) in waterjet cutting. Traditional methods like laser cutting or plasma cutting generate heat, which can cause distortion, warping, or discoloration in the material being cut. Waterjet cutting, on the other hand, eliminates the risk of heat-related damage.
This is how each method compares to water cutting in the key aspects of application so that you can decide whether you need a water jet or plasma cutter (or any other type of cutter)r:
- Plasma cutting. It uses a jet of ionized gas to cut through electrically conductive materials, such as metals. It can cut faster and thicker than water jet cutting but also produces more heat, noise, and waste. Plasma also cannot cut non-conductive materials, such as plastics or ceramics, and may damage or distort the material.
- Laser cutting. It uses a focused beam of light to cut through various materials, like metals, plastics, or wood. When facing off waterjet cutting vs laser cutting, the obvious areas of difference are speed and somewhat accuracy – lasers cut faster and with more accuracy than water jet cutting, but they also produce a lot more heat and waste. It’s also not applicable to reflective or transparent materials, such as glass or mirrors.
- Mechanical cutting. It uses a blade, saw, or drill to cut through various materials. It’s generally faster and cheaper than water jet cutting, but it also produces more noise, waste, and stress. It lacks precision as it cannot cut complex shapes or designs and may damage or deform the material due to mechanical force.
A battle of choices that many professionals face when looking for the most effective cutting method is that of wire EDM vs waterjet cutting, mainly for various industrial applications. Wire Electrical Discharge Machining uses a thin wire and a spark to cut through conductive materials and excels in creating intricate shapes with high precision. However, it’s a thermal process that can create a heat-affected zone and is slower than waterjet cutting.
Choosing the Best Waterjet Cutting Machine
As for choosing the right waterjet cutting machine for your needs, you must consider several factors – the type of materials you will be cutting, the desired cutting speed, the level of precision required, as well as your budget.
If you primarily work with materials that can be easily cut with water alone, a pure waterjet cutter may be the right choice for you. However, if you frequently work with metals, ceramics, or composites, an abrasive waterjet cutter would be more suitable.
The desired cutting speed is another important factor to consider. Higher-pressure machines can achieve faster cutting speeds, at three times the speed of sound, but they may come at a higher cost. Assess your production requirements and determine the optimal balance between cutting speed and cost.
Lastly, your budget. There’s no easy answer to the question of how much a waterjetcutter is worth since waterjet cutting machines come in a range of sizes and capabilities. You should consider your budget constraints and invest in a machine that offers the best value for your money.
Safety Precautions for Waterjet Cutting
Given the high pressure and speed used when cutting with water, you might be asking yourself, is waterjet cutting dangerous?
While waterjet cutting is a safe cutting method compared to some traditional methods, you must adhere to proper safety precautions to prevent accidents or injuries. Here are some key safety measures to keep in mind when operating a waterjet cutting machine:
- Personal Protective Equipment (PPE). Always wear appropriate PPE, including safety glasses, gloves, and hearing protection, when operating a waterjet cutter. The high-pressure stream of water or a water-abrasive mixture can cause serious injuries if proper precautions are not taken.
- Machine Guarding: Ensure that the waterjet cutting machine is properly guarded to prevent accidental contact with the cutting stream. Adequate safety features, such as interlocks or barriers, to protect the operator from potential hazards are mandatory.
- Training and Supervision. Proper training should be provided to operators before they operate a waterjet cutting machine. Operators should be familiar with the machine’s operation, safety procedures, and emergency shutdown protocols. Strict supervision and monitoring of operators can help prevent accidents and ensure safe operation.
- Maintenance and Inspection. Regular maintenance and inspection of the waterjet cutting machine are essential to ensure its safe operation. Any damaged or worn-out components should be replaced promptly, and the machine should be kept clean and free of debris to prevent malfunctions.
Conclusion
Understanding what waterjet cutting is, from its working principles to the different types of machines available, is essential when you’re considering implementing it.
By choosing the right waterjet cutting machine, adhering to proper safety precautions, and maintaining the machine regularly, you can harness the full potential of waterjet cutting and achieve exceptional results in your manufacturing endeavors.
FAQs
1. How many psi is a water jet cutter?
The typical water pressure used in a water jet cutter ranges from 20,000 to 60,000 PSI). However, some water jet cutters can operate at pressures up to 90,000 PSI. The exact pressure used can vary depending on the specific application and material being cut.
2. Who can operate a waterjet cutter?
A waterjet cutter can be operated by individuals who have received proper training. This typically includes machine operators, engineers, technicians, CNC operators, and other trained professionals who have undergone the required training.
3. How is the cutting path determined in a waterjet cutter?
A computer-controlled system usually determines the cutting path. The operator inputs the desired design into a CAD (Computer-Aided Design) program, which then controls the cutter to follow the specified path.