Production Machining

OCT 2017

Production Machining - Your access to the precision machining industrial buyer.

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pallet and pick up next part blank. If the measurement is found out of tolerance limits, hold the part and alarm the operator with message of what dimension is out of expected limits. 7. L oad next part and measure at set frequency. Depending upon capability, measurement can be set at 100 percent or 1 in 50, 1 in 10, and so on. Tool wear can also be set based on cutting tool wear history. For example, with tool life expectancy of 200; measure X-Z for tool path (typically the tightest tolerance), 1 in 5 for the first 20 parts, then 1 in 50 for the next 130 parts, then 1 in 10 for the last 50 parts. e integral probe is handy to have for trending these inspections. Collision Avoidance e pick-up sequence is located in its own subprogram, which is provided with the machine. is allows the customer to input values such as number of pallets, workpiece heights, and so on, making programming easier and in effect custom- izing the machine to the shop's application. Application Examples For shops looking to consolidate chucking operations into a single machine tool platform, the inverted vertical design has a proven track record and some inherent advantages. One application example is the machining of planetary carriers. With the vertical process, one of EMAG's customers could finish turn primary datums and then finish pinion holes with using the machine's fixed spindles. Machine basics for this application included loading automation, glass scales, precision C-axis direct-drive spindle, a rigid polymer- concrete base and temperature-controlled machine (maintaining ambient) provided the precision necessary to make these complex parts complete. In another successful application machining output shafts, the customer was able to reduce the shop's number of spindles from 60 horizontal lathes to 34 vertical lathes (VL chucker and VT shaft machines combined to make a VTL DUO). Reduction in spindle count was accomplished by optimizing the machining process and live tools. e integrated automation for load/unload, faster load/unload times six to eight seconds versus 12-14 seconds loading by robot. A Cellular Approach e inverted vertical design is basically a self-contained manufacturing cell. Designed for medium to high produc- tion of chucker and shaft part blanks, it can machine green or hardened parts complete. e automation is a stand-out feature in the machine's design. Using a standard O-loop conveyor and a simpler automation concept that combines workholding for load/ unload instead of grippers and special parts pushers, it is an elegant and efficient solution to material handling. e workzone is compact, making part-to-part distances relatively short for faster load/unload of part blanks. Accuracy is also built in with the use of a thermally stable cast polymer-concrete base with excellent dampening and high strength glass scales, roller guideways and cooling unit to maintain the machine at ambient temperatures. Rigidity and thermal stability are critical for hard turning and finish grinding applications. For shops running banks of horizontal turning centers, it might be worth looking into implementing inverted vertical turning for chucked part blanks. For more information about vertical turning machines from EMAG, call 248-442-6590 or visit emag.com. Collision avoidance is programmed into the machine parameters and monitored by sensors. An example of this would be at the pick-up station. At this station, EMAG machines are fitted with a sensor to detect part presence and also includes a gimbal table. e gimbal table not only allows for precise pick up of the workpiece blank, but if the blank is not sitting flat, the gimbal-table will flex to allow the part to sit flush with a locator on the chuck. e gimbal table also monitors stroke distance. is distance is how much the workpiece displaces the table and should be within set limits. If there is a misloaded part, part is oversized/undersized, operator double stacked parts, this condition would be detected to avoid a collision. For another article on this topic, visit the link below. LINK :: short.productionmachining.com/vtl :: The part conveyor system can be equipped with a gimbal table that triggers an alarm if the part is misloaded. Programming for Inverted VTLs productionmachining.com :: 39

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