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Integrating flexibility key to designing the manufacturing cell

As competition forces manufacturers to find ways to become more and more nimble, the focus of flexibility ultimately finds its way to the shop floor. The pace of new product development, the need to produce and rework an array of parts, the ability to handle machining a mix of materials and to achieve varying volumes and unit costs, all these requirements make the reconfigurable, flexible cell concept a highly competitive advantage.

Likewise, a reconfigurable slide selection can now be designed for varied machining tasks. For example, a belt-driven, high-horsepower, horizontally-mounted spindle might be combined with hardened boxways for maximum rigidity when milling cast iron, while roller bearing axis construction teamed up with a high-speed, vertically-mounted, integrally motorized spindle would be ideal for cutting aluminum molds.

With the advent of high speed machining technology, a single CNC spindle module can now achieve heretofore unheard of flexibility by designing in reconfigurable options for a variety of spindle and way combinations. For example, using the same column for different applications, a belt-driven, high-horsepower, high-torque spindle configuration might be used for steel or cast iron, then changed on site to a high speed, integrally-motorized spindle configuration to cut aluminum or composites. For light duty milling and drilling, a turret head that delivers .7 second tool-to-tool exchange might be attached.

The trick: a column designed to accommodate mounting holes for both types of ways so they can be changed on the shop floor. A simple method for achieving horizontal, vertical or centered mounting options is to design the column to be able to be rotated 90 degrees then remounted on the base axes with the same holes.

The design of the column structure should be as light and stiff as possible since those characteristics are requisite for both high speed, light loads and high torque, heavy cuts. Finite Element Analysis (FEA) can forecast deflections, helping to design a small footprint cell with maximum work envelope.

This new breed of flexible manufacturing cell design possibilities allows manufacturers to quickly tailor a single machine to tackle specialized applications across a broad range of power, load, speed and material variables, and to do so at a fraction of the cost of traditional custom machining solutions. By designing with options to enhance flexibility, the reconfigurable CNC module's economy and efficiency become instantly apparent.