Erè machin-nannan
• Pozisyon – presizyon echèl lineyè, erè plon vis boul-, repèkisyon (±2–5 µm tipik).
• Jeyometrik - kare ant aks, enklinezon file koton, dwat nan fason (kreye cône oswa fòm bannann).
• Tèmik - 1 degre chanjman ≈ 11 µm/m sou fason asye; kwasans spindle ak pati lakòz flote pandan kouri long.
Zouti ak erè koupe
• Mete zouti – mete flan VB > 0.05 mm agrandi dyamèt, wonn bor.
• Devyasyon – L/D > 4:1 lakòz 5–20 µm klòch-bouch oswa vè lè-.
• Chip re-koupe - mikwo-chip grate sifas, ogmante Ra 0.2 → 0.6 µm.
Workholding & done erè
• Varyasyon fòs kranpon aparèy – konpresyon pati elastik 2–8 µm; lage apre yon-klanp.
• Chanjman Datum – chèz inegal oswa chip anba lokalizatè deplase zewo 5–15 µm.
• Chuck machwè kouri-soti – 3-machwa woulo liv bay 2–6 µm erè konsantirite sou re-mandrin.
Mezi ak echantiyon erè
• CMM dyaman koube - 3 mm dyaman, 0.2 N fòs ≈ 1 µm devyasyon.
• Diferans tanperati – pati 5 degre pi cho pase CMM ajoute ~6 µm sou 100 mm Al.
• Patipri echantiyon – mezire sèlman pati "bon-gade" gonfle Cpk pa 0.2–0.3.
Erè materyèl ak estrès
• Lage estrès rezidyèl - apre yo fin retire po 0.5 mm, pati Al 7075 defòme 10-40 µm sou span 100 mm.
• Chanjman faz – 420 SS chalè-zòn ki afekte a elaji 0.01%, chanje gwosè twou 2 µm pou chak 20 mm.
Erè anviwònman
• Boutik-etaj tanperati balanse 2 degre/èdtan – pati asye 200 mm grandi 4 µm.
• Vibration – charyo élévateur ki tou pre oswa laprès kout pwen an ka kite mak chatter 1–2 µm pwofondè.
Erè imen / pwogramasyon
• Zouti konpanse typo – 0.1 mm kle-nan erè toujou pase chèk patwouy si kalib la se 0.15 mm ki lach.
• Move direksyon konp kouto – Iwa-imaj la koupe de fwa reyon kouto a.
Règ-de-pile gwo pous-
Pou yon pati aliminyòm 50 mm sou yon machin 3 µm, atann:
Machin 3 µm + Tèmik 2 µm + Mete zouti 2 µm + Kranpon 2 µm + CMM 1 µm → ± 10 µm total.
Tolerans konsepsyon dwe pi gran pase oswa egal a 20 µm pou frape Cpk 1.33.
Anba liy
"Precision" se pa espèk machin lan; li se sòm tout sous erè ou idantifye, mezire ak kontwole.
