What Is Water Jet Machining?
The machining process in which water jets are used to extract material from the workpiece is called water jet machinings (WJM).
In this process, water jets are used, which acts as a device in the form of a water saw. In this process, the water is raised very rapidly and further focused on the target workpiece.
At a high velocity and pressure, it is capable of using some abrasive particles mixed in water jet materials and some metals.
In some processes, no abrasive is used, & these processes are known as pure water jet machining processes.
The water pressure used in this machinings process varies from 200 MPa to 400 MPa.
The pressure varies according to the workpiece from which the material is to be removed. This process is similar to the water erosion phenomenon that exists in nature.
It is mainly used to remove materials from soft and non-metallic workpieces such as plastics, rubber, glass, etc.
A high-velocity water jet is used in this process to remove materials from the workpiece.
The basic principles of this process are that the kinetic energy of the water jet must be converted into pressure energy so that it removes the material from the workpiece.
When the jet of water collides with a workpiece with kinetic energy, this kinetic energy will be converted into pressure energy.
This pressurized energy will induce stress to the workpiece, and due to this, the tension material will start to move away from the workpiece.
Working Principle of Water Jet Machining:
It is based on the principles of water erosion. When a high-velocity jet of water hits the surface, the material is expelled.
Pure water jets are used to machine soft materials. But to cut hard materials, some abrasive particles are mixed with water for machining, and it is called AWJM (Abrasive Water Jet Machining).
Parts of Water Jet Machining:
The reservoir is used to store water that will be used as a jet. From the reservoir, water is supplied for the jet-jet machining process.
This pump will soak up the water from the reservoir, and it will transfer the water in intensity. The pumps are used to create pressure in water from 1500 to 4000 bar. To achieve this pressure, an electric motor of 50 to 100 hp is used.
Intensifiers are used to increase the water jet pressure and to produce high-pressure liquid jets. This intensifier is connected to the accumulator. It accepts water under low pressure and exhales it through an accumulator at high pressure. It works through a hydraulic reciprocating mechanism.
The accumulator is used to temporarily store water according to requirements. It is connected to the accumulator control valve. It maintains a continuous flow of high-pressure water and eliminates pressure fluctuations.
#5. Control Valves
This control valve controls the water pressure as well as the amount of water and directs it towards the flow regulator. This is where the pressure energies will be converted into kinetic energy.
#6. Flow Regulator
The flow of water arriving from the control valve is regulated using a flow regulator. After regulating the flow regulator, the water will pass through the nozzle, i.e., the high pressure of the water will be converted into high-velocity water.
This nozzle will cover the pressure of the high-pressure jet in kinetic energy. The kinetic energy increases as the field decrease at the end of the nozzle. The jet of water from the nozzle is then directed towards the workpiece.
The water which is directed from the nozzles will come out from this orifice.
#9. High-Pressure Tube
High-pressure tubes are required for high-pressure water to flow. They are about 6 to 14 mm in diameter. It also allows flexible movement of the cuttings head.
#10. Catcher or Drain
Catchers or drains are used to collect water after cutting the workpiece. From here, water is sent for further purification or can be reflowed.
Abrasive Materials of Water Jet Machining:
The most commonly used abrasive particles in Abrasive Materials of Water Jet Machining are garnet & aluminium oxide.
Sand (Si02) and glass beads are also used as abrasives. The function of abrasive particles is to increase the cutting efficiency of the water jet.
Working of Water Jet Machining:
First, the water is transferred at an intensity using a pump. The intensifier accepts the water under low pressure and then transfers it to the accumulator at a high pressure of about 3800 bar. The accumulator temporarily stores high-pressure water.
High-pressure water from the accumulator is transferred to a control valve that controls the direction of the water.
In the control valve, the water pressure energy is converted to kinetic energy, i.e., high-pressure water is converted to high-velocity water, and this high-velocity water is sent to the flow regulator.
The flow regulator controls and controls the flow rate of the water and directs it towards the nozzle. In the nozzle, the kinetic energy of the water increases significantly, and the nozzle produces high-velocity water.
Then the water comes out of the hole and is directed towards the workpiece. When the jet of water reaches the workpiece, the kinetic energy again changes to pressure energy, and the workpiece will be under full pressure.
This pressure due to the water jet will cause some fractures on the part of the workpiece where the water jet bike and some cracks will be introduced into the surface of the workpiece and as the water jet continuously strikes the surface of the workpiece for a long period of time, it will initially The crack will deepen and therefore the material will be removed from the workpiece.
The material that is extracted is carried away with water. After the removal of the material, the water that cuts the material is collected for further use.
The material in this water will contain parts of the chips which are cut using this process. This water will be sent for further purifications, or the water can be reassembled through the entire process of jet machining.
Advantages of Water Jet Machining:
Here, the different Advantages of water jet machining are as follows:
- It has the ability to cut material without disturbing its original structure.
- And this is because there is no heat-affected zone (HAZ). It is capable of producing complex & intricate cuts in material.
- The work area remains clean and dust-free in this machining process.
- Its operating and maintenance costs are low because it has no moving.
- Thermal damage to the workpieces is negligible due to no heat generated. It is capable of cutting soft materials (WJM) such as rubber, plastic, or wood, as well as hard materials (AWJM) such as granite.
- It is environmentally friendly because it does not create any pollution or toxic products.
- It has greater machining accuracy. Inches tolerances of 0.005-inch order can be easily obtained.
Disadvantages of Water Jet Machining:
Here, the different Disadvantages of water jet machining are as follows:
- It is used to cut soft materials. But AWJM can cut rigid materials of limited thickness.
- Very thick material cannot be prepared by this process.
- The initial cost of WJM is high.
Also, Read: Centrifugal Casting
Application of Water Jet Machining:
Here, the different Applications of water jet machining is as follows:
- Water jet machinings are used in various industries such as mining, automotive, and aerospace to cut, shape, and streamline operations.
- Materials that are usually mechanized by water jets (WJM or AWJM) are rubber, textiles, plastics, foam, leather, composites, tiles, stone glasses, food, metal/paper, and more.
- WJM is mostly used for cutting soft and easy machined materials such as thin sheets and foil, wood, non-ferrous metal alloys, textiles, honeycomb, plastics, polymers, leather pieces, frozen, etc.
- AWJM is commonly used to machine materials that are hard and tough to machine. It is used to machine steel, Al and other commercial materials, reinforced plastics, metal matrix, ceramic matrix composites, layered composites, stone, glass, etc., thick plates.
- Apart from the machining process, high-pressure water jets are used in paint removal, surgery, cleaning, peeing, etc., to remove residual stresses.
- AWJM can also be used for drilling, pocket milling, turning, and reaming.
Frequently Asked Questions (FAQ)
Abrasive Water Jet Machining
The abrasive particles used for AWJM are typically silicon carbide and aluminium oxide. The abrasive particle is intentionally embedded in a jet of water to increase the MMR of the process.
Water Jet Machining
Water Jet cutting uses an ultra-high pressure stream of water to carry an abrasive grit. The abrasive does the cutting through a mechanical sawing action, leaving a smooth, precision cut surface. Waterjet is the most versatile process because it is able to cut almost any type of material.
Water Jet Cutting Machine Working Principle
Waterjet cutting is simply an accelerated erosion process within a selected material. The highly pressurised water is fired through a ruby or diamond nozzle into a mixing chamber. This pressure creates a vacuum and draws garnet sand into the stream where it is then fired at the object in place for cutting.
Applications of Water Jet Machining
Abrasive waterjet cutting machines efficiently cut stone, marble, ceramics, porcelain and tile. Waterjet cutting is ideal for the insertion of inlays, and logos for stone and tile applications, as the process effectively maximizes performance, reduces cost and increases profit.
Precision Water Jet Machining for Metal Fabrication
Precision water jet machining is an effective method for metal fabrication, allowing for precise cutting of various metals with minimal heat-affected zones. This process involves using a high-pressure water jet, often mixed with an abrasive material, to cut through the metal. Here are some key points about precision water jet machining for metal fabrication:
- Cutting Capabilities: Water jet machines can cut a wide range of metals, including stainless steel, aluminum, titanium, copper, brass, and more. The process is versatile and can handle different thicknesses of metal, from thin sheets to thick plates.
- Accuracy and Precision: Water jet machining offers excellent accuracy and precision, with tolerances as low as +/- 0.003 inches (0.08 mm). This makes it suitable for applications that require intricate designs, complex shapes, or tight tolerances.
- Non-Heat-Affected Zone: One significant advantage of water jet cutting is that it is a cold-cutting process. It does not generate heat during the cutting operation, minimizing the heat-affected zone (HAZ) and preventing changes to the metal’s structure, such as heat distortion, hardening, or warping.
- Minimal Material Waste: Water jet cutting is a highly efficient process, as it produces minimal material waste. The narrow kerf width of the water jet allows for tight nesting of parts, maximizing material usage and reducing costs.
- Versatility: Water jet machines can cut through metals of varying thicknesses and shapes, making them suitable for a wide range of applications. Whether it’s intricate decorative pieces, structural components, or precise parts for industrial machinery, water jet machining offers versatility in metal fabrication.
Water Jet Cutting Vs. Traditional Machining Methods
Water jet cutting and traditional machining methods are two different approaches to material cutting and fabrication. Here are some key points comparing water jet cutting with traditional machining methods:
- Cutting Mechanism: Traditional machining methods, such as milling, turning, and drilling, typically involve the use of sharp tools (e.g., drills, end mills, lathe tools) to physically remove material from the workpiece. Water jet cutting, on the other hand, utilizes a high-pressure stream of water or a combination of water and abrasive particles to erode and cut through the material.
- Heat Generation: Traditional machining methods generate heat due to the friction between the cutting tool and the workpiece. This heat can affect the material, leading to thermal distortion, hardening, or changes in material properties. Water jet cutting is a cold-cutting process that does not generate significant heat, reducing the risk of heat-related issues in the workpiece.
- Material Compatibility: Traditional machining methods are versatile and can be applied to a wide range of materials, including metals, plastics, wood, and composites. Water jet cutting is also versatile and can cut through various materials, including metals, stone, glass, ceramics, composites, and more. It is particularly useful for cutting materials that may be challenging to machine using traditional methods, such as heat-sensitive materials or those prone to melting or warping.
- Precision and Tolerances: Both water jet cutting and traditional machining methods can achieve high precision and tight tolerances. However, water jet cutting typically offers better precision for intricate shapes and contours, thanks to its ability to create complex cuts without tool deflection or wear.
- Surface Finish: Traditional machining methods can produce varying surface finishes depending on the cutting tool and parameters used. Water jet cutting generally provides a smoother surface finish, especially when using finer abrasive particles or pure water cutting. However, additional post-processing may still be required for achieving specific surface requirements.
Affordable Water Jet Machining Companies
Finding affordable water jet machining companies can vary depending on your location and specific project requirements. However, here are some general approaches you can take to find affordable water jet machining services:
- Obtain Multiple Quotes: Contact multiple water jet machining companies and request quotes for your project. Provide them with detailed specifications, including the material, dimensions, quantity, and any specific requirements. By comparing the quotes you receive, you can identify companies that offer competitive pricing.
- Local and Regional Companies: Explore local and regional water jet machining companies. They may have lower overhead costs compared to larger companies, which can translate to more affordable pricing. Additionally, working with local companies can sometimes save on shipping or transportation expenses.
- Online Marketplaces: Consider utilizing online marketplaces or platforms that connect customers with water jet machining service providers. These platforms often allow you to compare prices and reviews, helping you find affordable options that suit your needs.
- Small and Medium-Sized Enterprises (SMEs): Small and medium-sized enterprises, including machine shops or fabrication shops, may offer competitive pricing for water jet machining services. Reach out to SMEs in your area and discuss your project requirements to see if they can provide affordable solutions.
- Negotiation and Flexibility: Engage in discussions with the water jet machining companies and be open about your budget limitations. Some companies may be willing to negotiate the pricing or offer alternative solutions to meet your affordability requirements.
Water Jet Cutting for Architectural Designs
Water jet cutting is an excellent choice for architectural designs due to its versatility, precision, and ability to handle various materials. Here are some points to consider when using water jet cutting for architectural designs:
- Material Selection: Water jet cutting can work with a wide range of architectural materials, including metals (such as stainless steel, aluminum, and brass), stone (such as marble, granite, and limestone), glass, ceramics, composites, and more. This flexibility allows for the incorporation of different materials into architectural designs, enhancing aesthetics and functionality.
- Intricate and Detailed Designs: Water jet cutting is capable of producing intricate and detailed designs with high precision. It can cut complex patterns, curves, angles, and even 3D shapes, enabling architects to create unique and visually appealing elements for their designs.
- Customization and Personalization: With water jet cutting, architectural designs can be customized and personalized according to specific requirements. Whether it’s intricate decorative patterns, signage, logos, or personalized elements, water jet cutting allows for precise and detailed customization.
- Versatility in Applications: Water jet cutting can be used for various architectural applications. It can create decorative panels, room dividers, cladding elements, balustrades, staircases, flooring patterns, signage, artwork, and more. The possibilities are extensive, limited only by creativity and design intent.
- Seamless Integration: Water jet cutting allows for seamless integration of different materials and components in architectural designs. It can cut precise joints and connections, enabling smooth transitions between materials and facilitating the assembly and installation processes.
Abrasive Water Jet Machining Working Principle
Abrasive water jet (AWJ) is a cool cutting technology to cut difficult to cut materials. In the AWJ machining process, the workpiece material is removed by the action of a high-velocity jet of water mixed with abrasive particles based on the principle of erosion of the material upon which the waterjet hits.
Water Jet Machining Working Principle
WJM utilizes kinetic energy of water jet to remove material from workpiece. The Jet has a high velocity of up to 900 m/s which strikes the work surface where the kinetic energy instantaneously changes into pressure energy up to a scale of three times higher than normal stagnant pressure.
Wjm Machining Process
The Water Jet Machining (WJM) process is an advanced, non-conventional machining process wherein a water jet is fired at the workpiece. The jet erodes the material of the workpiece and causes it to become shaped, i.e. jetting is a machining process that utilizes a water jet to remove material from a workpiece.
How Thick of Steel Can a Water Jet Cut?
Waterjet cutters can cut through 9 inches of stainless steel. Anything thicker increases the cutting time significantly. Some applications reconfigure waterjet systems to cut through even 18-inch steel blocks. However, in many applications waterjet cutters are utilized to cut 4-inch steel.
Can a Waterjet Cut Diamond?
Since diamond is the hardest material in the world, only the waterjet machine can cut it.” The OMAX 2626 is a high-precision waterjet machine often found in research labs, tech prototyping, and even aerospace facilities. The waterjet is fast and efficient utilizing optimized Intelli-MAX® software.
Is Water Jet Cutting Better Than Laser?
Laser cutting has an advantage over waterjet cutting when it comes to precision. Although both techniques provide good accuracy, laser cutting is significantly more accurate. This can be cut with an accuracy of 0.15 mm. Waterjet cutting, on the other hand, enables a cutting precision of 0.5 mm.