Application case: automotive connecting rod
Finishing of the pin hole in a heavy-duty diesel engine connecting rod, with Hanna HR® cermet insert. Cylindricity of 3 µm, hole tolerance of 2 µm, 2,000 parts produced without adjustment.
Context
Component: forged connecting rod in SAE 1141 steel. Piston pin hole, Ø 32.000 H7. Volume: continuous production line.
Hanna HR® Solution
- Family: HR2 monoblock
- Insert: cermet (
_H), TiAlN coating - Interface: HSK-A63
- Vc: 180 m/min
- fz: 0.12 mm/tooth
- Coolant: internal 40 bar
Measured results
| Metric | Specification | Achieved |
|---|---|---|
| Diameter tolerance | H7 = +25 µm | ±2 µm within nominal |
| Cylindricity | ≤ 5 µm | 3 µm |
| Parts per insert change | — | 2,000 parts without adjustment |
| Edge change time | — | ≤ 25 s, no preset, no zero reset |
| Carbide consumption | Reference (solid reamer) | −85% |
Why it matters
2 µm hole tolerance + 3 µm cylindricity + 2,000 parts between adjustments means process stability of Cpk class ≥ 2.0 in real production, with auditable tungsten and cobalt savings.
Replication
Applicable to any connecting rod, shaft, crankshaft, cylinder head, or engine block with an H7 hole between Ø 27 and Ø 35 mm. Use the configurator to assemble the equivalent tool for your Ø.
Perguntas frequentes
- Is the number 2,000 parts without adjustment typical or exceptional?
- Typical. In medium-alloy ISO P steel with 40 bar internal coolant and a cermet insert, 1,500 to 2,500 parts per edge is the expected range.
- Can I reproduce the same result on my shop floor?
- Yes, provided there is a minimum internal coolant pressure of 20 bar and a hydraulic or shrink-fit chuck. Hanna offers process auditing during the initial setup.