Advancements in Single-Pass Bore Finishing - Systems Approach (pag. 8 of 10)

Advancements Manufacturers are continually pushing the envelope in regards to what can be accomplished with the singlepass Processo. Improved tool, fixture, and machine designs have allowed for increased production rates as well as improved bore precision. The following are some of the latest advancements that have been made. Long Length to Bore Ratio: One of the myth’s that has been associated with the singlepass Processo is that it is only well suited for finishing relatively short bores. As illustrated in some of the case histories in this paper, bores with length to diameter ratio’s of over 10 to 1 do not present a problem. With the proper tooling, fixture, and machine tool, the singlepass Processo is even capable of removing a camber or “banana” condition from the bore in many Applicazionis.

Long length to diameter ratio gun barrels finished with single-pass Processo

Diameter:	11.26mm	Length:	165mm
Material:	Stainless Steel	Hardness:
Bore Type:	Thru	Stock Removal:	0.130mm
Tool Pass #1:	11.163mm	Diamond Size:	40/45
Tool Pass #2:	11.190mm	Diamond Size:	40/45
Tool Pass #3:	11.217mm	Diamond Size:	40/45
Tool Pass #4:	11.244mm	Diamond Size:	40/45
Tool Pass #5:	12.258mm	Diamond Size:	100/120
Tool Pass #6:	12.265mm	Diamond Size:	200/230

Bore Quality	Required	Achieved
Size:	.012mm	0.005mm
Roundness:	.012mm	.005mm
Straightness:	.005mm	.002mm
Surface Finish:	0.30Ra	0.25Ra

Machine Type:	Engis Model # 9825-16 (6 Spindle Machine)
Coolant:	Engis SP2240 Levigatura Oil
Production:	50 Parts Per Hour

Special Note: Peck Style Motion, QuickChange Fixtures.