Press Release Summary:
Worldflex Microfinishing System achieves circular geometry and surface finish on main and pin journals. Two models handle parts from 10 to 60 in., covering 95% of world's crank sizes. Parts are loaded between headstock and tailstock mounted on slide. Tooling is mounted to end of microfinishing arms, each of which is mounted on its own independent slide. Changeover to process different parts is accomplished by repositioning, adding, or removing arms.
Original Press Release:
New Microfinishing Systems Slashes Changeover Time; How Crankshafts are Finished to Perfection
Providing the flexibility to microfinish a variety of automotive crankshaft sizes with a single machine, IMPCO Machine Tools' new Worldflex Microfinishing System. Allows engine manufacturers to produce bearing finish and geometry (roundness improvement) on crankshafts and camshafts to extreme tolerances, in relatively short cycles, and will speed up changeover to process different size shafts, compared to previous methods. Microfinishing is the final operation on crankshafts and is the only way to achieve today's tight tolerances.
The first application of this new concept is at Krupp Gerlach in Danville IL, producer of crankshafts for Deere, Detroit Diesel, and Caterpillar.
Any crankshaft can be processed with this machine and microfinishing technique. Only two size machines cover a part size range from 10" to 60", making the Worldflex series capable of handling 95% of the world's crank sizes, IMPCO says, adding that some automotive OEM's are considering increasing levels of flexibility and producing crankshafts on systems designed for lower production, such as 25-60 pph. With a Worldflex system, the automotive industry particularly will be able to respond economically to varying production volumes and process a range of current and future product sizes.
Machine designed for flexible production.
Parts are loaded between a headstock and a tailstock mounted on a slide. The servo-driven ball-screw slide can position the part anywhere along the travel axis of the machine to present the bearing journals to microfinishing tooling. The tooling is mounted to the end of microfinishing arms, each of which is mounted on its own independent slide. The variable positioning of the part and the flexible positioning of the tooling are the keys to the flexibility of Worldflex, according to the company. Previous types of microfinishing systems are equipped with fixed-position tooling and parts are indexed to a predetermined location at each station.
"Which and how many arms are used to process any shaft is determined by required production rate, the number of bearing journals on the shaft to be microfinished, and the level of quality required," said Norm Judge, IMPCO Vice President Marketing. "Each Worldflex machine is equipped with only the number of arms required to process the crankshaft at a specified production rate. Changeover to process a different part can be easily accomplished by repositioning, adding, or removing arms, if needed."
Each arm package is mounted on a linear bearing rail on bottom and top for maximum rigidity. These rails are mounted on two additional perpendicular rails, allowing the user to adjust positions of the arms to accommodate part centerline and journal locations for virtually any crank configuration, according to the company. These rails, while enabling changeovers, also assure the stability and squareness of the arms to the crank centerline. Each arm has its own supply of microfinishing medium (tape) and indexing ability, so tape is only consumed where machining occurs.
Production capacity of a Worldflex is variable. Each machine is programmed to engage only the number of arms required to process the part design at desired production rates. This permits the user to use more arms per cycle to process more journals simultaneously for high production rates or fewer, as production dictates.
"Worldflex allows the user to quickly adjust production rates and to changeover to process a range of part sizes, providing levels of flexibility that microfinishing never had," pointed out Jim Vasilenko, IMPCO Vice President of Sales.
In a recent example, Worldflex processed three sizes of a nodular iron crankshaft-perfecting the surface finish, roundness and size of the journals with three levels of microfinishing-at a rate of 18 pph.
On a series of crankshafts, for example, the centerline spacings remain constant, but the spec required GBQ Level II microfinishing at 18 pph. Arms advance to Level I on two mains, two pins, and finish oil seal surfaces. Slides pull back and head and tail stock shift sideways, radially reorient crank, and microfinish the next two mains and pins to GBQ Level I while four additional arms microfinish the first two mains and two pins to the required Level II. The part shuttles again to accomplish the next level of microfinishing, and shuttles again to accomplish Level II and thrust wall. The different levels of IMPCO GBQ Microfinishing are applied as necessary to achieve geometry and surface finish specifications. Total cycle time 200 sec. to achieve specified surface finish, roundness, and size.
Krupp Gerlach specified IMPCO's patented Generating Bearing Quality (GBQ) microfinishing process to achieve circular geometry and surface finish on all main and pin journals and a high degree of flexibility to permit processing a range of crankshaft sizes in the range of 20 cranks per hour.
The innovative Worldflex microfinishing system provides the flexibility, process control, and production rates Krupp required.
IMPCO Machine Tools is the world's leading designer and builder of microfinishing machines and systems and is the developer of the patented GBQ (Generating Bearing Quality) microfinishing process for dramatically, statistically and consistently optimizing bearing journal size, geometry and surface finish to improve part function.
For more information on Worldflex, contact Jim Vasilenko at IMPCO (517)484-9411.