Single set-up processing can be designed to perform multiple operations but it is common to use multiple single set-up processors instead.  Typically time is lost in the transfer from one single set-up processor to another. 

• Palletizing workpieces off-line and then clamping them in common receivers can achieve dramatic setup reductions.
• Workholding accounts for two of the biggest setup problems. Specifically, these are repeatability of location from one workpiece blank to the next, plus transfer of work from one machine tool to another while maintaining relative position of related geometric features on the work-in-process.
• Palletizing a workpiece blank off-line may eliminate probing for a datum on the initial setup and the need to re-establish a datum when moving from machine to machine. Saving setup time by eliminating load/unload variability is driving the application of palletized work in shops.
• When loading, even the most conscientious operators are challenged to accurately place each blank in its fixture. Slight variation in position, especially for tight tolerance parts, can result in scrap and re-work.
• Machine tool builders have made major advances in single setup processing using machine tools designed to perform multiple operations—single machines that can turn and mill for example. Even so, many workpieces require the processing services of more than one machine tool for completion.
• Traditionally when loading a new job on a machine, accurate location of the blank or blanks must be established prior to the machining cycle. This is usually done with a touch probe or gage block.
• Likewise when moving a workpiece from one machine tool to another, it is necessary to reload the partially machined part into a fixture or vise and then establish a datum point from which to continue the processing. Time can be lost in this transfer because of the need to re-establish location of the workpiece on the second machine tool.
• In most metalworking shops, pallets are associated with machining centers, flexible manufacturing cells, and systems.
• Loading workpieces off-line onto a tombstone or other fixture enables shops to make significant improvements in spindle utilization.
• But there is another kind of palletizing.
• Once the location of a blank is established, relative to the pallet, that data can be captured electronically. Work can then be moved from a turning center to a grinder, or from a machining center to a CMM, without the need to relocate the reference point.
• The system is composed of two components, a chuck or receiver, and a pallet
• Using this setup technology, five sides of the workpiece are accessible to the machine tool cutter.
• Palletizing a workpiece augments pallet shuttles and can give many of those pallet-shuttle benefits to single-table machine tools
• Once the various alignments are established on the machines, it is not necessary to re-establish them from one job to the next. That's where a significant amount of setup time reduction can be realized.
• In metalworking, standards among equipment makers have been elusive. Reluctance to establish compatibility between unlike machines and accessories carries over into both hardware and software.
• While there are efforts underway to change some of this, achieving open architecture is a daunting task.
• Much of the burden of standardization falls on the shop's shoulders. Tooling is an example.
• For workholding, the problem of standardization is more complex because of the huge variety of applications.
• Standardization gives a shop the ability to interchange work among various machine tools. However, it is modularity that gives the shop a method of dealing with various applications.
• If a shop made one part by the millions, then standardization of workholding, tooling, material transfer, and measurement would be sufficient to reap large manufacturing efficiencies.
• Modularity is key to processing different sizes and shapes of workpiece blanks.
• It is accuracy that makes the concept of palletization a viable solution.
• Eliminating the variability of workpiece loading and unloading is a big step to more consistent quality. That's one major advantage to a palletizing system.
• The design of the pallet and its receiver guarantee consistent placement of a workpiece in a machine tool whether it is done by hand or by an automated material handling device.
• The critical component of this system is the steel centering part. It operates using the assumption that radial positioning, axial positioning, and clamping are separate functions within the chucking unit. One or four draw studs couple with four punched holes; or, hardened centering plates establish radial positioning.
• For axial positioning, hard stops called supporting feet create hard contact between the chuck and the pallet. Once in contact, the four feet form a plane. The centering plate, in contact with the prisms, flexes slightly and self-centers. The action is repeatable, giving the system its accuracy.
• Clamping is achieved using a ball lock mechanism. The lock is positive. It is pneumatically actuated and designed to be fail-safe. Air actuates the opening of the chuck only. It closes mechanically, so if the air is cut off, the chuck remains securely clamped.

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