Advance Machining Process.

 Machining has come a long way since the days of manually operated lathes and milling machines. With the advent of computer numerical control (CNC) machines and other advanced technologies, machining has become more precise, efficient, and versatile. In this blog, we will take a closer look at some of the latest advanced machining processes and their benefits.

High-Speed Machining

 

 

High-speed machining (HSM) is a cutting-edge manufacturing technology that involves using advanced tools, high spindle speeds, and rapid feed rates to remove material from a workpiece at a much faster rate than conventional machining processes. It is an efficient and cost-effective technique that can be used to produce parts with greater accuracy, better surface finish, and reduced production time. In this article, we will explore the basics of high-speed machining, its advantages and disadvantages, and its various applications.

Basics of High-Speed Machining

High-speed machining is a technique that involves removing material from a workpiece at a high rate of speed, typically above 20,000 RPM. The technique relies on the use of specialized cutting tools, such as carbide or diamond-coated end mills, which can withstand the high forces and temperatures generated during the machining process. High-speed machining also involves using high-pressure coolant to remove chips and prevent heat buildup, which can cause tool wear and damage the workpiece.

Advantages of High-Speed Machining

Faster machining time: High-speed machining allows for the removal of material at a much faster rate than conventional machining processes, which reduces production time and increases efficiency.

Better surface finish: High-speed machining can produce parts with a smoother surface finish, which reduces the need for additional finishing processes such as polishing or grinding.

Improved accuracy: The use of high-speed machining can result in greater dimensional accuracy and tighter tolerances, which is especially important for complex parts with intricate geometries.

Longer tool life: High-speed machining can extend the life of cutting tools, resulting in lower tooling costs and reduced downtime for tool changes.

Disadvantages of High-Speed Machining

Higher equipment costs: High-speed machining requires specialized equipment, such as high-speed spindles, which can be more expensive than conventional machining equipment.

Greater demands on tooling: High-speed machining requires specialized cutting tools that can withstand the high forces and temperatures generated during the machining process. These tools can be more expensive than conventional cutting tools.

Increased risk of tool breakage: High-speed machining can put greater stress on cutting tools, increasing the risk of tool breakage and damage to the workpiece.

Applications of High-Speed Machining

High-speed machining is used in a variety of industries, including aerospace, automotive, medical, and mold and die making. Some common applications of high-speed machining include:

Complex 3D shapes: High-speed machining is ideal for producing complex 3D shapes, such as impellers and turbine blades, that require intricate geometries and tight tolerances.

Thin-walled parts: High-speed machining can be used to produce thin-walled parts with greater accuracy and reduced distortion.

Hard-to-machine materials: High-speed machining can be used to machine hard-to-machine materials, such as titanium and Inconel, which are commonly used in aerospace and medical applications.

Electrical Discharge Machining (EDM)

 

Electrical Discharge Machining (EDM) is a non-traditional machining process that uses electrical energy to remove material from a workpiece. In this process, an electrode, which is usually made of copper or graphite, is used to create a spark between it and the workpiece. The spark generates intense heat that melts and vaporizes the material, which is then removed by flushing the area with a dielectric fluid.

EDM is a highly precise machining process that can be used to produce complex shapes and features in hard and difficult-to-machine materials such as titanium, tungsten carbide, and hardened tool steels. The advantages of EDM include:

1.High precision: EDM can produce very intricate and precise shapes that cannot be achieved with conventional machining processes.

2.Hard and difficult-to-machine materials: EDM can be used to machine hard and difficult-to-machine materials that cannot be machined with conventional processes.

3.No tool wear: In EDM, the electrode does not contact the workpiece, so there is no tool wear, which results in longer tool life.

4.No residual stress: EDM produces very little residual stress in the workpiece, which is important for parts that are sensitive to stress.

There are two types of EDM: wire EDM and sinker EDM. Wire EDM uses a thin wire as the electrode to cut the workpiece, while sinker EDM uses a specially shaped electrode to create the desired shape in the workpiece.

Wire EDM is commonly used for cutting complex shapes and thin sections in materials such as tungsten carbide, tool steel, and titanium. Sinker EDM, on the other hand, is used for creating complex shapes and features in hardened tool steels, dies, and molds.

One of the drawbacks of EDM is its slow cutting speed, which limits its use for high-volume production runs. However, with the advancements in EDM technology, such as the development of faster EDM machines and improved control systems, the cutting speed has increased, making it a viable option for production runs.

Overall, EDM is an excellent choice for machining complex shapes and difficult-to-machine materials. Its ability to produce precise and intricate shapes, along with its capability to machine hard materials, make it an indispensable machining process in the manufacturing industry.

Ultrasonic Machining

 

 

Ultrasonic Machining (USM) is a non-traditional machining process that uses ultrasonic vibrations to remove material from a workpiece. In USM, a tool, known as an ultrasonic horn, is used to vibrate at high frequencies (usually between 20 and 40 kHz) in a vertical direction against the workpiece. The horn is typically made of a hard, brittle material such as tungsten carbide, and is mounted on a machine that provides the necessary power to drive the vibrations.

The tool is held in contact with the workpiece while a slurry of abrasive particles and a liquid (usually water) is introduced to the interface between the tool and workpiece. The vibrations of the tool create a series of high-frequency impacts that cause the abrasive particles to impact and remove material from the workpiece.

Ultrasonic machining is commonly used for machining brittle and hard materials, such as ceramics, glass, and sapphire, that are difficult to machine with conventional processes. The benefits of ultrasonic machining include:

1.High precision: USM can produce precise shapes and features with high dimensional accuracy and surface finish.

2.No thermal damage: Since USM does not produce any heat, there is no thermal damage to the workpiece, which is important for materials that are sensitive to heat.

3.No tool wear: The tool used in USM does not come in contact with the workpiece, so there is no tool wear, which results in longer tool life.

4.Reduced machining force: The use of ultrasonic vibrations reduces the force required to machine the workpiece, which is beneficial for delicate and brittle materials.

One of the limitations of USM is its slow cutting speed, which is typically lower than that of other non-traditional machining processes such as EDM and waterjet cutting. Additionally, the equipment required for USM is more expensive than that of other machining processes.

Overall, ultrasonic machining is an excellent choice for machining hard and brittle materials with high precision and surface finish requirements. Its ability to produce intricate shapes and features without causing any thermal damage to the workpiece makes it an essential machining process in various industries such as aerospace, biomedical, and electronics.

Laser Machining

 

Laser machining is a process that uses a focused beam of light to remove material from a workpiece. This process is ideal for machining materials such as polymers, metals, and ceramics. Laser machining can produce high-quality surface finishes and precise cuts, making it an ideal process for creating medical devices and aerospace components.

Laser machining can be used to cut, drill, engrave, and weld a wide range of materials, including metals, plastics, ceramics, and composites. The process is highly precise, with the ability to achieve tolerances of less than 10 microns. It is also a non-contact process, which means there is no tool wear, and there is minimal heat transfer to the workpiece.

One of the most significant advantages of laser machining is its ability to machine complex geometries with high precision. The laser beam can be programmed to follow any path or shape, making it ideal for creating intricate parts and components. The process is also highly repeatable, which means that identical parts can be produced with a high level of accuracy.

Another advantage of laser machining is its ability to produce high-quality surface finishes. The laser beam produces a very fine cut, which results in a smooth surface finish with minimal burrs or roughness. This makes laser machining ideal for creating components that require a high level of surface finish, such as medical devices and electronic components.

Laser machining is also a highly efficient process, with the ability to machine materials at high speeds. This can result in reduced cycle times and increased productivity, making it ideal for high-volume production. The process is also highly versatile, with the ability to machine a wide range of materials, including those that are difficult to machine using traditional methods.

Waterjet Cutting

 Waterjet cutting is a versatile and precise cutting process that uses a high-pressure stream of water to cut through a wide range of materials, including metals, composites, stone, and ceramics. The process involves forcing water through a small orifice at pressures up to 60,000 PSI, creating a stream of water with enough force to cut through the toughest materials.

One of the advantages of waterjet cutting is its ability to cut through virtually any material. Unlike other cutting processes, such as laser or plasma cutting, waterjet cutting does not produce heat, which means it can cut through materials that are sensitive to high temperatures, such as plastics and composites. Additionally, waterjet cutting can cut through thick materials that would be difficult or impossible to cut with other methods.

Waterjet cutting is also a very precise process, with the ability to achieve tolerances of +/- 0.005 inches. The cutting process is controlled by a computer program, which means that complex shapes and patterns can be cut with high accuracy and consistency. This makes waterjet cutting ideal for creating parts and components with intricate shapes and designs.

Another advantage of waterjet cutting is its ability to produce a smooth surface finish. The high-pressure water stream cuts through the material cleanly, leaving no heat-affected zone or burrs. This means that parts and components produced using waterjet cutting require minimal post-processing, resulting in faster production times and reduced costs.

Waterjet cutting is also a very environmentally friendly process. The cutting process uses only water and garnet abrasive, which means there are no harmful chemicals or fumes produced. Additionally, the water used in the cutting process can be recycled, reducing water consumption and waste.

One of the drawbacks of waterjet cutting is its slower cutting speed compared to other cutting processes, such as laser or plasma cutting. However, advances in technology have increased the cutting speed of waterjet cutting, making it a more competitive option for high-volume production.

Conclusion

Advanced machining processes are changing the face of the manufacturing industry. High-speed machining, electrical discharge machining, ultrasonic machining, laser machining, waterjet cutting, and multi-axis machining are just a few of the processes that are being used to create intricate and complex shapes with high precision and accuracy. With continued development in these processes and new technologies, we can expect to see even more advances in the machining industry in the coming years. These advancements will not only improve the efficiency of the manufacturing process but also allow manufacturers to create products with increased complexity and precision.

References:

https://www.thomasnet.com/articles/custom-manufacturing-fabricating/high-speed-machining-advantages-and-disadvantages/

https://www.canadianmetalworking.com/cutting-tools/high-speed-machining-toolpaths-feeds-and-speeds'

https://www.thomasnet.com/articles/custom-manufacturing-fabricating/waterjet-cutting

https://www.machinedesign.com/mechanical-motion-systems/article/21833134/waterjet-cutting-a-technology-overview

https://www.fabricatingandmetalworking.com/2016/02/the-basics-of-laser-cutting/

https://www.thomasnet.com/articles/custom-manufacturing-fabricating/electrical-discharge-machining-edm

https://www.thomasnet.com/articles/custom-manufacturing-fabricating/ultrasonic-cutting-the-basics

Contributors:

1.Yash Thorat

2.Uday Valvi

3.Prajwal Wani

4.Devshri Zope