【正文】 ave been around long enough in various configurations for manufacturers to appreciate their potential for costsaving, quality production of parts from miniature connectors to transmission housings for offhighway equipment. Development of true multitasking machines, however, has removed them from the category of special machines.Manufacturers have made them one of the fastest growing categories of CNC machine tools because they improve petitiveness. They offer the flexibility to meet justintime delivery of a variety of parts in smaller lot sizes. They consolidate the processes of many machines, improve accuracy, and save time formerly required for multiple setups as work was moved from machine to machine and operation to operation. Finally, they employ resources of people and capital equipment more efficiently, a definite plus that the most astute accountants can appreciate.The most familiar multitasking machines are NC lathes with live tools in the turret, millturns, and Swiss turning centers. NC lathes with a Y axis that allows turrets to move from side to side have full milling or drilling capability. They can mill, drill, and machine off the spindle centerline. A B axis allows rotation around the Y axis for drilling at an angle or contour milling.sand dollars to over a million dollars. That hardly qualifies them as modity machines。 yet, increasingly, these multitasking machines form the backbone of advanced machining operations for everyone from contract manufacturers to OEMs.Trends in the design of multitasking machines include packing more punch into a limited and crowded work area with extra slides, more horsepower, even matching sub spindle horsepower to that of the main spindle, putting more driven tools in the cut at the same time, and developing sophisticated software and controls for collisionavoidance, scheduling, and production analysis.For machine tool manufacturers with extensive experience in building CNC lathes and turning centers, developing multitasking machines is a natural next step.Romi Machine Tools Ltd. (Erlanger, KY) developed its multitasking E series turning centers to perform turning, boring, milling, and tapping in one setup in a machine with a pact footprint. The E 320 turning center can be configured with one or two spindles, C axis, live tools, and Y axis for mid to highvolume production. The left spindle features a beltdriven cartridgestyle gearless headstock with a hightorque 25 or 35hp ( or ) GE Fanuc AC spindle motor with a variable speed drive.The right spindle can match the left spindle with a similar 25hp spindle motor. The slantbed style E 320 series has a swing of (700 mm), a maximum cutting length of (600 mm), distance between spindle faces of (1048 mm) and a cutting diam of (320 mm). The E series includes an E 280 model, which features 15hp () spindles, as well as a doubleturret, doublespindle E 220 model.pressure coolant, air blast, tool touch probe, and part sensor. The Hardingedesigned and built jaw chuck/colletready spindle design permits faster spindle speeds for faster cycle times and maximum part rigidity as parts are gripped close to the spindle bearings, resulting in increased concentricity.When equipped with Hardinge39。s patented HydroGlide hydrostatic linear guideway system, the Quest CNC lathes have the rigidity and precision required for hard turning, as well as the improved crash protection that hydrostatic design offers.The concept of done in one rules today, especially as plex parts can be machined from bar stock or from solid, often eliminating the leadtime and expense involved to design and produce castings and forgings. Manufacturers have been quick to recognize and study their potential for maintaining critical tolerances between features by eliminating multiple setups and the time and accuracy lost moving from operation to operation.At its Technical Center, Caterpillar Inc. (Peoria, IL) works in alliance with its machine tool suppliers to evaluate the potential of equipment and processes that can range from prototype work to production for nextgeneration Caterpillar equipment, according to Jim Reeb, director of manufacturing research and development. Caterpillar is currently working with Cincinnati Lamb39。s H5 Geminex series machine for machining and turning powertrain ponents.The H5 Geminex machine is a flexible solution for processing mediumsized and large parts requiring milling and turning in a single setup, bining four and fiveaxis machining and highspeed turning.We39。re doing some horizontal types of machining and turning on ductile housings, says Reeb. We39。ll develop the process at the Tech Center and once it39。s worked out, we39。ll release the machine to our Decatur, IL facility for installation and production.Early experience with the potential of multitasking machine cells led Sandvik Mining and Construction (Sandviken, Sweden) to move production of its DTH (downthehole) rock drilling bits from the lowcost manufacturing environment of Mexico to Sweden in 2001. The DTH rock drilling bits are made from alloy steel forging blanks in 200 different types, of which 15 types are most frequently produced in batches varying from eight to 48.Making the move possible was the performance of a multitasking cell featuring three Nakamura STS40 super multitasking turning centers with robotic workpiece handling. The cell is able to perform all turning, milling, drilling, and buttonhole drilling, including a hardening cycle, of the alloy steel DTH drill bits in five days with 12 operators. The previous conventional method required seven machines and 50 people. Standardizing on the Sandvik Coromant Capto interface and selecting twinedge tooling with two inserts in each toolholder enable each machine to independently perform plete machining of drill bits.The need to be petitive in its manufacturing processes is no less important to a machine tool builder