What heat treatment is applied to a marine engine crankshaft?
Short answer
| Purpose | Treatment | Temperature | Cooling |
|---|---|---|---|
| Dimensional stability, remove internal stresses | Stress relief | ≥ 550 °C | Furnace cool to ≤ 300 °C |
- Definition: stress‑relief heat treatment
- Purpose: achieve dimensional stability and freedom from internal stresses
- Process: heat to not less than 550 °C, then furnace cool to 300 °C or lower
- Applies to: cast crankshafts and similar castings
- Instrument: IACS UR W8 §5.2
Full answer
The full answer explains each point step by step, with the regulations and figures behind it and the discussion from other candidates. It is in the MEO Class II section of the Marine One forum, open to members enrolled for the MEO Class II exam.