SPECIAL FOCUS Metal Cutting Technologies
Precision Re-engineered As new application areas open-up in metalworking, the industry is witnessing new trends in machining technology, especially in automobiles, aerospace, energy and infrastructure. Registering a phenomenal growth, the metal cutting sector is garnering user attention with its latest technological advancements. Nishant Kashyap traces the evolving need for such developments for the industry.
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he metal cutting industry is well-known for catering to the automotive and aerospace industry for all types of vehicles. Metal cutting components constitute a major portion of inputs to these industries. Hence, there is a relentless drive to push for low tooling costs and quick deadlines. This has led countries from the West to focus on new tooling sources in the East where, costs are far low, and the companies get quality products within a stipulated time period.
Global Technological Trend In this competitive age, the production systems should be increasingly productive, environment friendly, precise, reproducible, and especially cost-effective. This requires optimally adapted processes with minimum stoppage and setup times. In addition, large forces in combination with high velocities are required for pressing, this call for advanced control technology. Manufacturers of production machines demand expandability and flexibility to meet customer requirements efficiently and cost-effectively. Due to limitations, high cost, speed and adverse side-effects of traditional metal cutting methods, chipless machining processes and technologies have been developed, such as automation, Numeric Control (NC) technique, electric discharge machining, waterjet, plasma cutting system 72
MODERN MACHINE TOOLS - January 2012
and laser machining techniques.
Plasma Cutting The plasma cutting process, as used in the cutting of electrically conductive metals, utilises this electrically conductive gas to transfer energy from an electrical power source through a plasma cutting torch to the material being cut. The basic plasma arc cutting system consists of a power supply, an arc starting circuit and a torch. These system components provide the electrical energy, ionisation capability and process control that is necessary to produce high quality, highly productive cuts on a variety of different materials. The speed, accuracy and range of materials that plasma cutting system can cut, has attracted automobile and steel companies to use it on a large scale. Plasma arc cutting is cheaper than oxyfuel and even faster especially for cutting steel up to two inches thick. It also provides greater speed than those of laser cutting systems for thickness over 0.125 inches. The plasma cutter has many advantages such as, it is equipped with latest techniques to cut the metal, it prevents the warping and paint damage that occur while cutting, it is faster and cost effective than other equipment and cuts the metal accurately. All these aspects make plasma cutting systems more suitable and have increased demand in the industry. “High definition plasma cutting has made