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Machine makes for flexible microfinishing

July 1, 2004
Customers come to Engine Power Components (EPC) Inc. in Grand Haven, Mich., for cam and crankshaft jobs. The shop specializes in using microfinishing to impart specified surface finishes on these parts for improving oil retention and, thus, enhancing thei

The Impco 640FX's flexibility and fast changeovers, let Engine Power Components easily microfinish such jobs as 4 and 6-cylinder diesel camshafts at a specified rate of 15 to 18 parts/hr.

Customers come to Engine Power Components (EPC) Inc. in Grand Haven, Mich., for cam and crankshaft jobs. The shop specializes in using microfinishing to impart specified surface finishes on these parts for improving oil retention and, thus, enhancing their performance and durability. Job volumes vary, as do shaft types and surface requirements, so EPC's microfinishing equipment must provide process flexibility and fast changeovers. For these reasons, the shop uses a model 640FX CNC microfinisher from Impco.

Because of the 640FX's flexibility, EPC easily microfinishes such jobs as 4 and 6-cylinder diesel camshafts at a specified rate of 15 to 18 parts/hr. Beyond this, the machine handles any cylindrical part up to 54 in. and features a 10-in. maximum-swing radius.

"Impco understands that the part's specifications and ultimately its performance drives our needs," says Peter Grose, EPC sales vice president. "And it provided us with a highly flexible machine with the benefits of its special GBQ microfinishing process."

The GBQ process perfects crank and camshaft geometries, surface finishes, and load-bearing journal sizes. The result is an engine that runs with much less friction and puts out more power, thus improving performance, reducing wear, and upping engine longevity.

In a single setup, the 640FX removes material from camshaft lobes using stone abrasives and processes main journals with abrasive film. Cam-lobe surface finishes are 0.25 µ with a 1.33 Cpk process capability, profile straightness and taper are within print specifications, Rsk (skewness) is less than zero, and waviness is within 100 µ in.

Key to the machine's flexibility is that users can choose which and how many microfinishing arms are used to process any shaft design. This depends on required production rates, the number of bearing journals on the shaft to be microfinished, and specified levels of quality. End users also have the option of using either stone or film-abrasive media.

The machine incorporates standard components and controls that Impco configures to deliver a reliable and easily maintained piece of equipment. Its compact design also lets the 640FX fit into EPC's cell-manufacturing strategy.

Impco Machine Tools
Lansing, Mich.
impco.com