Critical SOP: Braking & Sump Systems
Auxiliary Support & Flood Prevention
⚠️ BRAKING SAFETY
Context: Sleeve bearings rely on a hydrodynamic oil wedge. This wedge collapses at low RPM.
- The Danger: If the unit spins slowly for too long (> 5 mins) without stopping, the shaft wipes the bearing metal.
- Rule: Brakes MUST separate the pad from the disc automatically at > 15% RPM to prevent fire, but MUST engage firm at < 20-30% RPM to arrest rotation quickly.
SOP 1: Braking Logic
Controlled arrest of the 5-ton rotating mass.
1.1 Engagement Speed
- Set Point: Brakes should deploy automatically when speed drops to 20-30% of rated RPM.
- Too Early: Pad burning / Disc warping.
- Too Late: Bearing damage due to low-speed rotation without oil film.
1.2 Pad Maintenance
- Dust: Brake dust is conductive (mixed with metal). Vacuum it out after every 50 stops.
- Thickness: Replace pads when wear indicator is reached (typically < 5mm remaining material).
SOP 2: Machine Hall Sump Logic
The sump is the last line of defense against flooding.
2.1 Alarm Levels
- Level 1 (Start Pump): Pump 1 ON.
- Level 2 (High Level): Pump 2 ON + SCADA Alarm.
- Level 3 (Flood/Emergency): ESD (Emergency Shut Down) + Siren.
- Logic: If the sump fills faster than 2 pumps can clear, there is a major hydraulic rupture (MIV seal or Burst pipe). The unit must stop to reduce system pressure.
Summary Checklist
- Weekly: Test Sump Pump float switches (lift manually).
- Monthly: Clean Brake Dust from caliper area.
- Annually: Inspect Brake Pad thickness.