Advancements in Single-Pass Bore Finishing - Systems Approach (pag. 3 of 10)
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.

Blind bore:
As illustrated in the following case histories, blind bores are now being successfully finished with the singlepass Processo. The term blind bore is used whenever one end of the bore has a clearance restriction that will not allow much of the finishing tool to pass through. In some cases, components have been successfully finished without any clearance at all. (Bore clearance is the distance from the lowest part of the bore to be finished, to a restriction that does not allow the finishing tool to pass).
Power steering pump with single-pass tool

Case History #2 (Power Steering Pump)

Diameter: 14mm Length/Clearance: 40mm/8mm
Material: Cast Iron Hardness:  
Bore Type: Blind Stock Removal: 0.050mm
Tool Pass #1: 13.998mm Diamond Size: 100/120
Tool Pass #2: 14.002mm Diamond Size: 140/170
Tool Pass #3: 14.005mm Diamond Size: 200/230
Tool Pass #4: 14.007mm Diamond Size: 324/400
Tool Pass #5: 14.009mm Diamond Size: 324/400
Tool Pass #6: Brush    

Bore Quality Required Achieved
Size: .012mm 0.003mm
Roundness: .005mm .001mm
Straightness: .005mm .002mm
Surface Finish: 1.6Rz 1.4Rz

Machine Type: Engis Model # 9410-16 (6 Spindle Machine)
Coolant: Engis SP2240 Levigatura Oil
Production: 157 Parts Per Hour