BOS 45000

Common issues

• Wire rope wear, corrosion or broken wires exceeding discard criteria from heavy-lift duty cycles
• Slew bearing wear/backlash from sustained heavy overturning moments
• Hydraulic system contamination or seal wear in the luffing/hoisting cylinders and winches
• Load moment/limiting system calibration drift, affecting overload protection accuracy
• Structural fatigue cracking at high-stress boom connection points from repeated heavy lifts
• Sheave and pulley wear from sustained wire rope loading
• Anti-two-block and other safety device sensor faults

Inspection checklist

• Visual and NDT inspection of the boom structure at high-stress points per the class/maker schedule
• Wire rope inspection (broken wires, diameter reduction, corrosion) against the applicable discard criteria
• Function-test the load moment indicator/limiter against known test loads
• Check slew bearing bolt torque and backlash
• Pressure-test the hydraulic system and inspect cylinders/hoses for leaks or damage
• Function-test anti-two-block, overload and emergency stop devices
• Inspect sheaves and drums for wear or grooving
• Verify the current load test/proof load certification

Service intervals

Critical spares

• Wire ropes, hoist and luffing - correct diameter/construction only, no substitution without engineering approval
• Hydraulic cylinder seal kits
• Sheave/pulley bearings
• Slew bearing seals
• Load cell/load pin sensors for the load moment system
• Hydraulic filter elements

Safety

• Catastrophic failure risk from exceeding rated capacity - the load moment limiter must never be overridden or defeated
• High-pressure hydraulic system stored energy - depressurise and lock out before intrusive work
• Suspended-load hazards during heavy-lift operations - exclusion zones must be enforced
• Wire rope failure risk if discard criteria are exceeded - do not delay replacement

Class survey

Offshore heavy-lift cranes of this capacity are surveyed under the classification society's lifting appliance rules, with periodic load testing, NDT of structural welds, wire rope certification and load moment system function testing all required at survey - the documentation trail is what class actually checks.

Estimated lifetime: Heavy offshore cranes of this size are typically designed for a structural life of around 20-25 years or a specified number of load cycles under the applicable design code; treat this as indicative only - actual remaining life should be assessed from the crane's structural fatigue and inspection records, not from a generic hours figure.