What is Waterjet Cutting? Exploring the Technology Behind It

Waterjet cutting is a process that utilizes a computer-controlled (CNC) cutting machine, equipped with specialized software. This software orchestrates the movement of the cutting head, enabling it to slice through various materials or workpieces. A distinctive feature of waterjet cutters is their non-thermal cutting approach, which sets them apart in automation applications.

This technology finds extensive use in diverse areas, such as demolishing concrete structures and cutting through the advanced materials used in aircraft fuselages. Its precision significantly enhances the efficiency of the cutting process.

For more insights into the waterjet cutting process and its applications, continue reading as we delve deeper into the capabilities and benefits of this innovative technique.

What is Waterjet Cutting?

what is waterjet cutting

Waterjet cutting is a highly efficient and precise manufacturing process that uses a high-pressure stream of water, optionally mixed with abrasive particles, to slice through a variety of materials. This advanced cutting technology is capable of cutting intricate designs on materials as diverse as metals, composites, glass, ceramics, and stones without introducing heat or significant mechanical stress. This ensures that the structural integrity of the materials is preserved, making waterjet cutting particularly valuable for applications requiring meticulous detail and precision.

One of the standout features of waterjet cutting is its versatility. It can effectively handle materials that are difficult to cut with more traditional methods, such as heat-sensitive materials, which might warp or distort under other cutting processes. Additionally, it is environmentally friendly; it generates no hazardous waste and uses materials efficiently to minimize scrap. This combination of precision, versatility, and sustainability makes waterjet cutting a favored choice across various industries, including aerospace, automotive, and architecture, where precision and material integrity are paramount.

How Does Waterjet Cutting Work?

how waterjet cutting works

Waterjet cutting is an innovative technology that can be segmented into two main types based on the material and application: Abrasive Water Cutting and Pure Water Cutting. Abrasive water cutting is suited for hard materials such as metals, ceramics, and stones. It employs a high-pressure water stream mixed with abrasive materials like garnet sand to cut through tough surfaces. The process includes several key steps:

  1. A large electric pressure oil pump pushes water into a heavy-duty intensifier at 2750 psi.
  2. The pressure inside the intensifier is boosted from 50–60 psi to 55,000 psi due to the significant size difference between the hydraulic piston and the water piston—the hydraulic piston being 20 times larger.
  3. This ultra-high-pressure water is then directed through a steel pipe to a cutting head, where it is funneled through a precise orifice made of sapphire or diamond.
  4. The pressurized water and abrasive mixture exits through a nozzle, creating a potent cutting stream that can slice through hard materials efficiently.

Conversely, Pure Water Cutting uses only water at high pressure and is ideal for softer, more flexible materials like plastics, rubber, foam, and leather. Key aspects of this method include:

  1. Water is pressurized to create a high-speed jet capable of cutting materials cleanly without the use of abrasives.
  2. This technique is particularly effective for materials that are sensitive to hygiene and temperature, such as food and textiles.
  3. Although it has lower cutting power, pure water cutting excels in making precise cuts and intricate designs, especially in 3D shapes and fine details. The nozzle size can be as small as 0.1 mm, adjustable down to 0.08 mm for cutting complex materials.

Both techniques leverage the unique properties of waterjet cutting, offering precision and versatility without the heat-induced damage associated with other cutting methods.

Key Components of Waterjet-Cut Machining

key components of waterjet machine

There are several machine components involved in generating water flow from a high-pressure pump through plumbing and exiting through a tiny opening. The components include:

1. High-Pressure Pump

This high-pressure pump guarantees consistent pressurized water running at an effective cost. It is the heart of the waterjet system, where most of the primary activities occur. There are two types of high-pressure pumps used in waterjet applications: direct drive-based pumps and intensifier pumps. The direct drive-based pump is similar to the household washing deck, where the triplex pump detects the movement of the three plungers directly from the electric device. It delivers about 20,000–50,000 psi and Intensifier pumps generate high-pressure water that can cut through a water circuit or hydraulic circuit.

2. Abrasive Delivery System

This system operates using a metering device that can be set to different abrasive scales. Depending on the material, the ratio of abrasive to water for cutting material differs. The measurements are taken during the machine setup and are inputted once and for all until work delivery. The CNC’s adjustment of the nozzle speed is the only parameter in this process.

3. Cutting Head

This allows perfect precision alignment when it comes to waterjet technology. The cutting structure is designed into a Venturi chamber, jewel orifice, and mixing tube. The jewel orifice, where the pressurized water coming from the plumbing converts into high-velocity steam.

The venturi chamber is the point where there is a mixture of abrasive and water after the steam passes through the orifice.

The orifice and mixing tubes come in different sizes and diameters, depending on the provisions required. The mixture of water and abrasive exits the mixing tube.

4. Motion Equipment

A steady-state servo mechanism is what drives this. The cantilever system has an X-Y movement mechanism and structure to enable cutting heads to move freely over a cutting surface. The axis runs on specialized precision bearings, linear screws, and guide rails. The advantages of this motion equipment include:

  • Free workspace for loading and unloading materials or workpieces.
  • Operators have easy access to the cutting space.
  • The beam moves in one direction, eliminating the need for a precision dual-drive system.

4. Catcher Tank with Cutting Table

A movable catcher tank is capable of handling large and heavy workpieces. The tank collects water only and is abrasive during waterjet machining. A workable table is also placed on the tank to support work done during grating.

5. Control Software

The Computer Numerical Control (CNC) system is a pre-installed application designed in AutoCAD and stored in a DWG file. The control system automatically converts the file into numerical files that the system can interpret. The machine then understands how to direct the cutting head movement in the X, Y, and Z directions. This system is reliable, fast, and delivers precise accuracy.

Types of Waterjet Cutters

types of waterjet cutters

As explained above, the pressurized water that passes through the orifice and enters the Venturi chamber with steam that passes through a nozzle at high speed can increase the efficiency of the cutting head. There are two types of waterjet cutters:

Pure Waterjet Cutting: Uses and Materials

This is the original form of the waterjet cutting tool. It creates less moisture on the surface of the workpiece compared to when the cutting machine touches it. Furthermore, the pure waterjet cutter can cut soft and tough materials separated from pure filtered water since it generates no toxic waste in the process. What’s more, It can achieve a maximum added value of 90,000 PSI / 6200 bar due to its ease of operation.

  Uses of Pure Waterjet Cutter:

  • It has applications in the food industry due to its bacteria-free, hygienic cutting process.
  • It works great to cut corrugated cardboard, tissue paper, and automotive interiors due to its low moisture.

Advantages of a Pure Waterjet Cutter:

  • It operates with extremely low cutting force.
  • It can cut soft materials and light workpieces easily.
  • There is no heat generated in the cutting process.
  • It applies to any length and thickness of materials.
  • It has a very thin water stream.

Disadvantages of Pure Waterjet Cutter:

  • It does not cut metal workpieces.

Abrasive Waterjet Cutting: Process and Advantages

This cutter uses the pure waterjet cutting technique but requires additional components added to the cutting head. These components include focusing nozzles, mixing chambers, and abrasives. The abrasive agent mixed with the pure water jet creates a vacuum in the cutting head that leads to the mixing tube and exits focused through the nozzle for cutting. The abrasive material, such as garnet, is responsible for the intense mixing in the cutting head, leading to a sharper and higher ability to cut. It can cut materials as hard as aluminum.

Uses of Abrasive Waterjet Cutter:

  • Ideal for detailed cutting with its narrow kerf.
  • Cuts various materials like metals, stone, glass, and composites without tool changes.
  • Enables the creation of complex designs not possible with traditional methods.
  • Versatile for both one-off designs and mass production.

Advantages of Abrasive Waterjet Cutter:

  • Can carry out thin and thick material cutting.
  • Induces no mechanical stress.
  • It requires only one jet setup for various workpieces.
  • It produces a thin stream.
  • It results in minimal cutting of material waste.

Disadvantages of Abrasive Waterjet Cutter:

  • Abrasive and maintenance expenses make it pricier than other cutting methods.
  • It can be slower than laser or plasma cutting, especially for hard materials.
  • Used abrasive material needs proper disposal, posing operational and environmental challenges.

Types of Waterjet Cut Machines

waterjet cutting working process

The waterjet tool for cutting does not involve a complex cutting method because the CNC is programmable in a way that it cuts workpieces using the appropriate tools for different material types. Just like a brand-new saw, a waterjet cutter can perform single-axis cuts in 2, 3, 4, and 5 dimensions. Below is the list of cut machines used by manufacturing industries:

One Dimensional

This is a single-axis cutter for straight or linear cuts. The waterjet moves in one direction for this type of machine, which is often used for trimming the edges of a workpiece.

Two-dimensional

This cut involves an X-Y axis waterjet. Movement is achievable from the X-axis to the Y-axis. It does both linear and circular motion operations. Industries such as agriculture, mining, construction, and aerospace use 2-axis to slit materials faster than the traditional method. The technique works for a wide range of workpieces, and it has powerful and accurate capability without leaving a deformed edge. Finally, no burning processes make cutting in the environment convenient.

Three-Dimensional (XYZ)

This waterjet cut can move on the X-Y-Z axes. Each axis represents a particular direction or movement; it rigidly builds a machine tool frame. The machining has a user-friendly panel and high-pressure technology for enhanced precision, setup, and handling. Its flexible fixturing provides high dynamic capacity and accuracy.

Four-Dimensional (XYZA)

This cut is similar to the three-axis XYZ but includes a fourth rotary motion around the X-axis. The 4-axis cutter can also move circularly on the rotary A-axis around the X-axis. It can machine five sides of the material and make curved cuts, while also offering options for flipping the workpiece, allowing the waterjet to retract materials from the sides of the workpiece.

Five-Dimensional (XYZAB)

This 5-axis cutter can create linear, rotary, and inclined parts in one setup. Executing 2D and 3D cuts in various workpieces and most integral fabrication processes in aerospace, automotive, decor, and welding workshops is easy. The 5-axis machine is versatile, especially the G2 CNC machine. It is easy to operate and doesn’t need technical know-how; it also provides the best build quality in every product with maximum speed operation.

Waterjet-Cut Material

A variety of workpieces are versatile in all spheres of manufacturing industries. A waterjet cutter can cut through any material except diamonds and tempered glass. Materials that fall into this category include:

Metals 

It is applicable during metal fabrication. Various industries, such as engineering, architecture, electronics, and airplanes, use this as a value-added process with high accuracy, leading to increased productivity. Materials such as stainless steel, aluminum, carbon steel, mild steel, brass, iron, chrome, etc. are usable in the process.

Glass 

As a delicate material, the waterjet technique helps cut through medical optical glass, as glasses used for car windscreens reduce the risk of damage. It has high precision, accommodating a diverse range of materials and thicknesses. Examples of glass workpieces are mirrors, frosted glass, glassware, plain glass, and reinforced glass.

Stones: Waterjet applications in stone cutting are versatile, as they cut different types of stone, saving time and cost. The gentle cutting process minimizes material loss and leaves the structure and hardness unchanged. Cutting stones with a waterjet applies to kitchens, house flooring, and cladding. Raw materials include granite, porcelain, Silestone, tiles, marble, and Caesarstone.

Plastics 

Waterjet technology reduces melting and heat in cutting plastic, creating an environmentally friendly space. Manufacturers use waterjet services to make toys, bottles, signage, and other products since they are highly efficient and cost-effective. This material includes ABS, LHDP, Nylon, Styrene, etc.

Rubber 

Rubber is a soft material that requires extreme precision when cutting. Waterjets give high precision when cutting rubber, reduce the effect of heat and fume emissions, and increase speed delivery. Examples of rubber products that are cuttable with this technique include neoprene, nitrile, natural insertion rubber, and polyurethane.

Wood 

Waterjets can create different shapes from wood designs, giving them a clean, quality-cut shape, accuracy, and speed. It is applicable for making wooden electric guitars and carving of angular structure pieces for interiors. The cutting process cuts raw materials like plywood, strand boards, and medium-density fiberboard without delamination problems.

Advantages of the Waterjet Cutting Process

We can’t overemphasize the versatility of this technology, as it saves time and production costs for most manufacturers. Below are the benefits of waterjet processes:

Delivers Extreme Accuracy

Extreme precision is one of the valuable advantages of waterjet machining, with a cutting accuracy of (+/-) 0.0003 inch to (+/-) 0.0005 inch. Since waterjet cutting is a cold cutting process, there is no melting away of material, increasing the accuracy tolerance. The narrow stream of water ensures a high-precision waterjet cutting process.

Cuts Almost Any Material It Comes Across

There is no thickness limitation when using the waterjet cutter. It can cut through any thickness of material and can pierce through 100 feet of material thickness with ease, which is applicable in some special mining fields.

Utilizes Green Technology

The waterjet process utilizes green technology because the jet stream of water recycles into the chamber and cools any heat-affected zone. Hence, it is safe to say that it is an environmentally friendly process since it does not emit any toxic fumes that may be harmful to humans. It uses pure water with natural abrasive materials to cut the workpiece efficiently.

Generates Less Heat

Since this process requires no contact or frictional force, no heat reaction occurs where water is the coolant itself. There is no temperature rise in the cutting process; the formation of a heat-affected zone only takes place when the material at the cut location changes drastically.

No Secondary Finishing Required

Unlike other conventional methods of cutting that require edge finishing after each water cutting process, waterjet cutting doesn’t require any secondary finishing as a result of the material erosion that takes place on a particle level.

Industry Cutting Application Served by Waterjet and Its Product

The Waterjet technology is reliable and highly accurate across all aspects of the manufacturing industry. The products produced through this process vary depending on the type of material, size, shape, complexity, and use. Here are a few categories of applications across different fields:

Architectural Industry

CNC technology has had remarkable value in this sector; it processes excellent architectural design quality and performance.  It works great for making signage for commercial purposes, like a decorative waterfall. Customized designs are usually made from high strength materials. It works great with different materials, including plastic,  metals, and decorative panels; building components such as wood, most artwork installations for interior or exterior residential,

Automotive Industry

The high-speed cutting operation is the most amazing, unique feature waterjet technology offers the automotive niche. It gives room for rapid prototyping and customization, minimal material waste, and the cutting of diverse materials. Carbon Fibre, for example, reduces weight, improves aesthetics, and improves cost management. Raw materials such as aluminum and steel can be cut using this technique to produce vehicle parts.

Aerospace Industry

 This CNC technique helps grade rigid aerospace materials such as metal and polymers. It has high repeatability and precision with large speed cutting. Airplane components consist of metal panels in fuselages and turbines; therefore, surface finishing is a priority for better air resistance, safety, and aesthetics. The benefits of waterjets in aerospace serve numerous product purposes.

Electronic Industry

Waterjet technology is scalable in the electronic industry because manufacturers can use it to make tools such as semiconductor wafers; it is also the most precise option for cutting multiple-layer sheets, saving time. Several areas in the electronic industry use waterjet cutters, such as the frame of electronic devices, TVs, laptops, etc. Products such as circuit boards, panels, and enclosures are producible using raw materials such as copper, aluminum, lithium, silver, Gold, and plastic.

Food Processing  Industry

The USDA approved pure waterjet cutting because it offers sanitational value and productivity compared to other cutting alternatives. You can cut products such as vegetables, meats, candies, and cake with this ultrahigh-pressure waterjet technology. This process helps to clean the edge in the cutting quality of food items, and no bacteria transfer from food to the tool or vice versa. The cutting range is calculated with minimal kerfs, making it economical to avoid food waste. Manufacturers find it easy to operate, and it easily accommodates product changes.

Manufacturing Industry

Waterjet applications in manufacturing industries offer great benefits because they produce products faster and remove the need for additional procedures to finish the shape of a product. It is also great for the environment, as produces no pollutants and contamination associated with manufacturing. Examples of products are sheet metal patterns, shapes in sheets, and plates.

Medical and Surgical Equipment

The precision of the waterjet equipment benefits medicine because the process holds exceptionally tight tolerances in cutting angles. It has increased productivity levels and cutting speed. Most surgical equipment made from titanium, silicone rubber, and stainless steel is crafted in complex angular cuts used in medical procedures such as liposuction, liver resection, bone divisions, etc.

Comparing Cutting Technologies

It’s all right to compare different technologies for a successful production rate. Most cutting technologies are beneficial, although their cons outweigh the pros in terms of efficiency. Below is a clear comparison of other cutting alternatives to Waterjet.

Waterjet Cutting vs Laser Cutting

waterjet cutting vs laser cutting

Manufacturers use both laser and waterjet cutting methods, especially in the sheet fabrication sector. It is necessary to understand the fundamental principles of both processes before you choose between them. Although they are different processes, their applications are closely similar based on their usefulness.

Lasers can cut materials up to about 30 mm thick, although some lasers with higher power capacity can cut up to 40 mm deep. However, if you are looking to cut through thicker materials, a waterjet can cut through parts as thick as 250–300 mm. Laser cutting produces a large amount of toxic vapor; in this regard, waterjet machining is more environmentally safe compared to laser cutting.

Waterjet Cutting vs. EDM Machining

A waterjet cutting machine has ultra-high-speed efficiency compared to EDM cutting machines. It provides more precise timing (psi/hr) than the EDM machine. Although both machines offer great accuracy, in the case of high accuracy, an EDM machine provides the right data required. A waterjet machine is considerable for cutting parts that require high tolerance.

Both have advantages and disadvantages attached to their functionalities. When it comes to versatility, the waterjet machine has proven to be more useful in terms of cutting speed and working efficiency, unlike EDM, which cuts through only conductive materials. However, waterjet cutting equipment can be a little expensive as it requires more maintenance.

Waterjet Cutting VS. Plasma Cutting

The plasma machine can cut smoothly through many pieces of steel at an accuracy of +/-.01″–030” depending on the setup. As the thickness of the material increases, the plasma struggles to melt through the material, making it less clean. The waterjet, on the other hand, works great for cutting through any material. From hard steel to soft foam or food items.

Both waterjet and plasma are cost-effective methods of cutting materials. However, waterjets become more cost-conserving with thicker plates that the plasma machine can’t cut.

Conclusion

The positive impact waterjet cutting machines have on manufacturers or local industries is numerous. The convenience of using this machine without complexity makes it versatile and sustainable. Its precision process is incomparable, being a cold-cutting method, making it a more attractive option than other alternatives.

If you want to provide a standard cutting finish for your business, Waterjet gives the best value for your money because they are not only capable of cutting; they come with advanced software programs that make working stress-free.

FAQs

What is the Maximum Thickness for Waterjet Cutting Across Different Materials?

It can cut up to 24 inches in thickness. However, the thicker the size of the metal workpiece, the slower the cutting speed. But if you have the time needed to cut through large workpieces, then there is no limit to the thickness a waterjet metal cutter machine can handle.

How Accurate is CNC Waterjet Cutting?

Typically, CNC waterjets have a higher cutting tolerance, so it may be hard to measure the exact accuracy. The typical part tolerance range is between 0.003 inches and 0.005 inches.



Source link