Answer
Annealing certification is mainly required for wrought-iron loose gear because repeated loading causes work hardening, residual stress and loss of ductility. Controlled heating and slow cooling restore ductility and reduce the possibility of brittle failure. The certificate provides traceability and confirms that an approved competent person supervised the annealing and inspected the gear afterward. Modern steel and alloy-steel gear is normally exempt from annealing and is subjected instead to periodic thorough examination and NDT as required. Annealing must never be carried out indiscriminately because it may destroy the designed heat treatment and strength of modern lifting gear.”
The periodic annealing requirement primarily applies to old wrought-iron loose gear. Modern lifting accessories are normally manufactured from:
Carbon steel
Alloy steel
Quenched-and-tempered steel
Case-hardened materials
Routine annealing of such equipment can destroy the manufacturer’s heat treatment, reduce strength and invalidate its certified SWL.
Annealing consists of:
Heating the gear uniformly to the specified temperature.
Holding it for the required time.
Allowing it to cool slowly.
This reduces hardness and internal stress and restores ductility through recovery and recrystallisation of the metal structure.
new amendments
cargo handling gear, anchor handling windlasses, ER cranes all to be suitably type approved by RO/class and complete documentation about their capacities to be made available