Tag
#mechanical
4 topics across all disciplines.
Material degradation — sensitisation, hardness limits and galvanic attack
Why welding can ruin the corrosion resistance of stainless steel without touching the weld, what the three conditions for galvanic corrosion are and which one to break, why sour service controls hardness rather than strength, what carbon equivalent predicts, and why zinc and stainless are kept apart.
Non-destructive examination — choosing the method and reading the result
Why every NDE method is blind to something, what magnetic particle cannot do on stainless, why ultrasonics can miss a crack lying the wrong way, the difference between an indication and a defect, and why the examiner's qualification is part of the result.
Bearings, seals and lubrication — the parts that actually fail
How a hydrodynamic journal bearing carries load on a film of oil, why babbitt is deliberately soft, what a mechanical seal is really sealing, why the seal chamber environment decides seal life, and what an API 682 flush plan is doing.
Vibration and alignment — reading a spectrum and getting the shaft straight
Why 1X usually means unbalance and 2X usually means misalignment, what a proximity probe sees that a casing accelerometer cannot, why hot alignment differs from cold, what resonance does to an otherwise healthy machine, and why a coast-down tells you something a steady run never will.