Waterjet cutting has transformed the metal fabrication industry with its ability to cut through various metals with fantastic accuracy and efficiency. This advanced technology uses a high-pressure stream of water and abrasive materials to cut through metal like a hot knife through butter.

This article will cover everything you need to know about waterjet cutting metal. So, let’s dive right in!

Can A Waterjet Cut Metal?

Yes, a waterjet can cut metal. A water jet cutter is a powerful industrial tool that can cut various materials. It uses a jet of water or a mixture of water and abrasive material at very high pressure.

When the jet does not contain any abrasive material, it is called a pure waterjet or water-only cutting, and it is suitable for cutting soft materials like wood or rubber. When the jet has added abrasive material, it is called an abrasive jet, and it can cut hard materials like metal, stone, or glass.

How Does Waterjet Cutting Metal Work?

Waterjet cutting metal is a non-thermal process that uses a high-pressure stream of water mixed with abrasive particles to cut through materials. Here’s how it works:

Water And Abrasive

The waterjet cutting method is a mechanical sawing procedure that uses a fine stream of water combined with crushed garnet (or other abrasive materials) to create sharp particles. Garnet is commonly used for cutting metal plates due to its hardness.

Speed And Pressure

Water is pressurized to ultra-high pressure to cut through rigid materials, ranging from 50,000 to 90,000 PSI.

The water is then ejected through a small aperture, typically between 5 and 15 thousandths of an inch in diameter, resulting in a supersonic jet of water.

Incorporating Abrasive

The water stream passes through a chamber and mixes with the abrasive particles, ensuring they are thoroughly incorporated and traveling in the same direction. This mixture is then sent through a focusing tube or nozzle.

Cutting Process

The supersonic stream of water and abrasive emerges from the focusing tube and wears through the material.

Each abrasive particle erodes a small quantity of material, producing very little heat. The water stream rapidly cools any heat generated, preventing a heat-affected zone.

Straight And Accurate Cuts

The high speed of the water stream keeps the abrasive particles on a straight path even after they leave the focusing tube. This results in precise, straight cuts on various materials without a heat-affected zone.

What Types Of Metal Can Be Cut With A Waterjet?

Metal is a common and widely used material often cut in machining shops. Waterjets can cut these metals fast, accurately, and cleanly. Waterjet can cut a variety of metals with ease and precision. Some of the metals that waterjet can cut are:

Tool steel

This metal is hard to mill with conventional methods, especially after hardening. Waterjet cutting simplifies the profiling of tool steel.

Also, you can harden it before or after cutting. The hardness of the steel has little effect on the waterjet’s performance.

Titanium

This metal is rare and expensive and poses a challenge to traditional machining methods. Waterjet cutting offers a cost-effective solution for cutting titanium, allowing for tight nesting, optimal material use, and offcut reuse.

Waterjets also produce very little waste when cutting titanium. This means you can save some materials and get a neat and flawless finish every time! Waterjet cutting also preserves the quality of titanium, as it does not generate heat or stress.

Copper and brass

These metals are difficult to cut with conventional tools, as they tend to clog them. They are also unsuitable for laser cutting, as they reflect the beam.

Waterjet cutting can easily cut copper and brass without any problems, making it the best option for these metals.

Aluminium

Aluminum is one of the easier metals to cut with waterjets because of its relative softness. This metal is lightweight and strong but also prone to deformation.

Usually, a laser can cut aluminum up to 8 mm thick, but a waterjet can cut it up to 170 mm thick with excellent results. Waterjet cutting can also handle complex shapes and intricate details that aluminum requires.

Steel (mild and stainless)

This metal is suitable for plasma, laser, and waterjet cutting, even after hardening. Plasma can cut steel up to 80 mm thick, laser up to 25 mm thick, and waterjet up to 170 mm thick.

Waterjet cutting is a good option for heat-sensitive products, as it does not produce heat or heat-affected zones.

Alloys

Waterjets can also cut metal alloys that are usually hard to cut with other methods, such as Inconel and Hastelloy. Waterjets do not cause any burning, slag removal, heat distortion, or molecular change in these alloys.

Other cutting methods may take too long, stress the material too much, or wear out the cutting tools. Waterjets offer a more economical and efficient alternative.

Applications Of Waterjet Cutting Metal

Regarding precision cutting in the metal industry, waterjet cutting has emerged as a highly efficient and versatile solution. Here are the numerous applications of waterjet cutting in the metal industry:

Automotive Industry

Waterjet cutting machines have a wide range of applications in the automotive industry. They can cut vehicles’ external and internal parts with different types of waterjets. Abrasive waterjets are ideal for slicing through metal body panels, while pure waterjets can handle softer materials like carpets and insulation.

Waterjet cutting also allows for the creation of complex shapes and forms, such as intricate engine parts, with the help of five or six-axis machines. This multi-axis cutting process can reduce machining costs and increase the efficiency of producing many small components in the automotive industry.

One of the main advantages of waterjet cutting in the automotive industry is its ability to produce smooth and burr-free surfaces without generating heat, harmful gases, or vapors. It also minimizes the amount of waste material and ensures a high-quality finish.

Aerospace Industry

Waterjet cutting is crucial in the aerospace industry due to its versatility and precision. Whether shaping intricate spaceship pieces or cutting metal components for aviation engines, waterjet cutting ensures unparalleled accuracy and quality.

One of the critical advantages of waterjet cutting in the aerospace and aviation industries is its ability to cut heat-sensitive materials without causing thermal distortion or damage. This prevents even the smallest errors or structural faults and potentially disastrous consequences.

These industries extensively use waterjet cutters to fabricate composite materials for airplanes and produce parts for jet engines, turbine blades, and more. The method allows for the precise cutting of complex forms from materials like composites, titanium, and aluminum with astonishing precision. It can even handle materials up to eleven inches thick.

Electronics Industry

Waterjet cutting has many applications in the electronics industry, such as cutting silicon wafers and creating printed circuit boards. Also, the precise cutting and shaping of metal components for electronic devices, such as smartphones, laptops, and circuit boards, are now possible by waterjet cutting.

Waterjet cutters are suitable for this industry because they can achieve high precision without damaging fragile electronic components.

Waterjet cutting is also a cold process that does not produce any heat, which is beneficial for the electronics industry, where heat-sensitive components are involved.

Metal Fabrication

Waterjet cutting is widely used in metal fabrication processes. Whether it is cutting intricate shapes or creating precise holes, waterjet cutting offers unparalleled precision and speed. It can cut through thick metals, such as stainless steel and aluminum.

This makes it an excellent choice for fabricators who work with a wide range of materials. The clean cuts produced by waterjet cutting eliminate the need for secondary finishing processes, saving both time and money.

Defense Sector

Abrasive waterjet cutting is used to make parts and components for military equipment in the defense sector. It can cut Kevlar composites, which are used for vehicle and personal armor, as well as thick plates of heavy steel up to 250 mm.

Abrasive waterjet cutting is ideal for defense because it can slice through the toughest materials, such as metals, composites, and ceramics. It also offers advantages such as accuracy and creating complex shapes without changing the material’s molecular structure or properties.

Medical Sector

Waterjet technology has many benefits for the medical field, especially in manufacturing implants and prosthetics.

Waterjet cutting is ideal for the medical sector because of its precision and hygiene. It is used to cut small pieces of material for medical and diagnostic devices.

Architectural & Visual Arts

Waterjet technology can create complex and accurate cuts in stones, glass, metal, and other materials. It can cut thicknesses from 1 mm to 300 mm much faster and more efficiently than before.

This makes it suitable for architectural applications such as making stained glass windows and decorative metal panels.

Advantages Of Waterjet Cutting Metal

Waterjet cutting stands out from other technologies, such as EDM wire cutting, plasma, machining, laser, etc., because it has some unique advantages. Here are they:

Cost Efficiency

One of the main benefits of waterjet cutting is its low operating cost, which is only about $14.00 per hour. This is the final price after considering the product’s material, labor, profit margin, etc.

However, you must pay extra if you need to use abrasive material. The abrasive cost can range from $0.20 to $0.35 per lb. It can be utilized for up to $35.00 per hour, depending on the pump power and cutting duration.

Waterjet cutting also saves money in other ways, such as allowing a fast transition from design to cutting, fast cutting speed, and fast setup time. Since there are low tangential forces, you don’t need to clamp the material most of the time.

No Heat or Chemicals

Water and abrasive are the only materials used in this type of erosion, which is called a “cold cutting” technique. The water stream cools down any heat that produces during the erosion process. This eliminates the need for further processing by avoiding the bending, distortion, and material hardening that often occur with plasma, laser, and machining.

It is also safer for the environment and the operators because it does not produce any vapor or smoke. Any dust that is generated during the erosion process is trapped in the water and safely filtered out later.

Excellent Edge Quality

The edge quality that waterjet cutting provides is one of the main reasons why professionals choose it. Waterjet cutting involves hitting the object with a very thin stream of water.

This means that metal cutters are not rubbing the object. This results in a smooth finish and excellent edge quality.

Multiple Cut Shapes and Multi-axis Cutting

Waterjet cutting is not limited to cutting in straight lines. You can also make other cut shapes on the workpiece. Good waterjet cutters also come with additional software with many cut shapes already programmed.

Waterjet cutting is also a multi-axis cutting method. You can cut in 5 different axes with a good waterjet cutter. This makes creating complex parts, such as small engine parts, easier. The benefits of 5-axis waterjet cutting over traditional 3-axis methods are flexibility, cutting speed, and less human labor.

Lower Cutting Tolerances and Better Accuracy

The cutting tolerance is the difference between the expected cut and the actual cut made by the cutting process. The cutting tolerance reflects the cutting process’s accuracy (or lack of accuracy) in simple terms. The lower the tolerance, the higher the accuracy.

The tolerance for waterjet cutting is one of the lowest available. One of the main reasons for this is because a tiny water stream does cutting. Another important reason is that waterjet cutting does not involve melting off of materials because it is a cold-cutting method.

Versatility/Flexibility

Almost every industry uses waterjet cutting because it can cut nearly any material at a reasonable cost and without altering the material’s properties. The waterjet can cut materials from 0.010″ acrylic to 10″ stainless steel. You can even stack thin materials to increase efficiency and reduce costs.

These machines have tables of different sizes, from 0.5m x 1.5m to 2m x 4m. But some custom-made machines can fit huge tables up to 4m × 18m and support multiple heads.

Tips And Precautions For Waterjet Cutting Metal

Waterjet is an industrial cutting tool. Therefore, it deserves the same safety precautions. If you follow the tips given below, you will ensure your safety during the cutting process. These safety procedures you should not ignore, as they could prevent fatal accidents.

Protective Gear

Waterjet cutting requires special safety equipment compared to other industrial operations. Make sure you wear hydro jet cutting safety pressure protection gear. Safety gloves come in different types. Wear Kevlar-reinforced cut-resistant safety gloves from the waterjet technology association for proper protection.

Also, wear the proper ear protection to avoid hurting your ears. Safety goggles are essential to prevent eye damage. Check if your safety glasses have ISO approval. Additional protection includes helmets, knee and shin guards, and knee pads. You should never go near the waterjet stream, even with extra safety measures.

Learn How to Use the Motion Controls

A waterjet machine can move 100 inches of material per minute at maximum speed. That’s very fast, like trying to play tag with a hungry cheetah. Keep both hands away from it when the machine is working.

It’s OK to stop and double-check everything if something is not cutting the way you want it to. It’s better to do a job a little slower than to get hurt and not finish it at all.

Read The Safety Manual Before Personal Use

Always read the operator safety manual before using a waterjet for personal use. If you own a waterjet cutter, you have to make your own waterjet safety rules. Learn the basic meaning of the safety symbols used in each hydro-cutting or water jet-cutting process step.

Your safety and your family’s safety depend on you doing this important step. Following the instructions also prevents damage to the equipment.

More Things to Remember

Ensure your environment is suitable for your work when using a waterjet cutter. Does the equipment you want to use have the proper safety warnings and instructions on it? If not, move on!

Are you following all the rules and regulations set by your employer? Reviewing them now would be a good idea if you haven’t done so in a while.

Conclusion

In the metal fabrication world, the cuts’ quality is crucial. Whether you’re working with stainless steel, aluminum, or any other type of metal, achieving precise and smooth cuts is essential for making high-quality products. One technology that has changed the metal cutting industry is waterjet cutting.

Waterjet cutting has transformed the metal fabrication industry with its accuracy, flexibility, and efficiency. Using the power of water and abrasive particles, this technology continues to expand the possibilities of what can be done in metal fabrication.

If you’re interested in purchasing a waterjet cutter for cutting metal, feel free to browse through our collection of state-of-the-art waterjet cutters. 

FAQs

• What are the limitations of water jet cutting?

Water jet cutting can only cut softer materials than the abrasive material used. This means that water jet cutting is unsuitable for hard materials like metals. Water jet cutting is also ineffective for materials that are thicker than four inches.

• What is the maximum thickness of metal that a water jet can cut?

A water jet cutter can cut stainless steel up to 9 inches thick. However, the thicker the material, the longer the cutting process.

However, you can modify some water jet systems to cut through 18-inch steel blocks for specific applications. But you can use most water jet cutters for cutting 4-inch steel or less.

• What is the taper of a waterjet cut?

This cut has a taper that is about 1.1 degrees in angle. The angle can vary depending on the material, cut quality, and material thickness.