1. Cov qib khoom siv tseem ceeb
Q:Cov qib steel dab tsi yog siv rau txias -cov raj precision?
A:
Cov pa roj carbon steel:
ASTM A519 1020/1026 (lub hom phiaj dav dav, σᵧ Ntau dua lossis sib npaug rau 350 MPa).
DIN 2391 St35 / St52 (Lub Tebchaws Yelemees), JIS G3445 STKM 13A (Nyiv).
Alloy Steels:
4130/4140 (Cr-Mo, rau siab- kev siv zog, hardness 200–300 HB).
Stainless hlau:
304/316 (ASTM A312) rau corrosion kuj.
Nco tseg:E355 (EN 10305-1) yog ib hom European qib rau hydraulic systems.
2. Chemical Composition Control
Q:Dab tsi yog qhov tseem ceeb ntawm cov khoom txwv?
A:
| Lub ntsiab | Limit (wt%) | Lub hom phiaj |
|---|---|---|
| C | 0.18–0.28 | Sib npaug zog / ductility |
| S/P | Tsawg dua lossis sib npaug li 0.025 | Tiv thaiv brittleness |
| Mn | 0.75–1.50 | Txhim kho hardenability |
| Ntsiab:Tsawg impurities (O / N Tsawg dua lossis sib npaug li 30 ppm) kom txias - kos duab ruaj khov. |
3. Kev tsim khoom & kev kho cua sov
Q:Cov raj no ua li cas?
A:
Kev kos duab txias:Txo OD / phab ntsa thickness los ntawm 20-40% rau nruj dua kam rau ua.
Annealing:700-850℃los txo kev ntxhov siab (ISO 10763).
Nto Finishing:Sib tsoo (Ra Tsawg dua lossis sib npaug 0.8 µm) lossis polishing (Ra Tsawg dua lossis sib npaug rau 0.4 µm).
Qhov tshwm sim:Tensile zog 500-800 MPa nrog cov qauv microstructure.
4. Dimensional Tolerances
Q:Dab tsi precision theem ua tiav?
A:
| Parameter | Ua siab ntev | Txuj |
|---|---|---|
| OD | ± 0.05 hli (ISO 3304) | ± 0.1 hli (ASTM A519) |
| Phab ntsa Thickness | Tsawg dua los yog sib npaug li 3% variation | Tsawg dua los yog sib npaug li 5% (welded hom) |
| Kev ncaj | Tsawg dua lossis sib npaug li 0.1 mm / m (laser- txheeb xyuas) | Tsawg dua lossis sib npaug li 0.3 mm / m (basic) |
5. Kev lees paub zoo & ntawv pov thawj
Q:Yuav ua li cas thiaj paub tseeb?
A:
NDT:Eddy tam sim no (ISO 10893-1), kuaj ultrasonic.
Mechanical Tests:Tensile (ASTM E8), hardness (HRB 70-90).
Cov ntawv pov thawj:ISO 10763, DIN 2391, PED 2014/68/EU.
