BLP Services team took on a huge refurbishing job on a 400te main deck crane auxiliary block on a multi-purpose, deepwater pipe lay and heavy lift vessel. This 400te working load limit (WLL) hook block is an auxiliary block on one of the three cranes on-board designed to support heavy lift, pipelay and subsea installations. Crane blocks require frequent inspections daily, periodic inspections quarterly to annually depending on use, and a complete disassembly and thorough inspection service every 5 years.
Our service technicians started with a complete inspection of the duplex hook and attachments checking for deformation, cracks, gouges, and thread wear. They then checked the latches on either side of the hook for proper function. The sheave wheels were inspected for misalignment, or wobble, and wear, and the proper positioning of sheave pin nuts. The rope grooves were checked for normal wear from use or for abnormal wear from misuse such as using improperly sized wire rope. This block is designed to be used with 2-3/4" diameter wire rope. All nuts, bolts, pins, and other hardware were double checked to make sure they were still installed and that they didn't show any signs of bending. The side plates, pins and axles, fittings and trunions were checked for signs of cracking and deformation. The block assembly was completely disassembled and any damaged or missing parts were repaired or replaced.
The refurbishing process included:
- Pre and Post Non-destructive testing (NDT)
- Blasting to remove all old paint
- All bearings and seals were replaced with new
- DNV witnessed, 110% overload pull tested (986,000 lbs.)
- Re-painted and tagged
- Full certification pack