Launch & Recovery Tool
To enable seabed trenching for subsea cable installation, Boskalis contracted TME for the design and fabrication of a launch and recovery tool.
The tool launches and recovers a trenching vehicle from a cable laying vessel into the ocean and vice versa. The tool forms a connection between an A-frame carriage and the trencher. It is designed to securely latch onto the trencher, pick it up from the deck, and hoist the trencher vehicle into the ocean. Conversely, the tool must recover the trencher from the ocean and place it back on deck in the correct position. To enable this in challenging weather conditions at sea, the main functionalities of the tool comprise:
- Latching with trencher
- Dampening of longitudinal and transverse motion of the trencher by hydraulic cylinders.
- Extendable (telescopic) for vertical displacement.
- Positioning of the trencher in the horizontal plane to place it straight on deck independently of how the trencher was submerged.
Since weight distribution impacts the vessel's stern stability, the tool is made from high-strength steel due to its favorable strength-weight ratio. The launch and recovery tool has received Lloyd's certification based on extensive load case and dynamics calculations.
Key facts & figures
| Project duration | 4 months including design and fabrication |
| Scope | concept engineering, detail engineering, production drawings, fabrication & lloyds certification |
| Deadweight | 70 tonnes |
| Load capacity | 70 tonnes |
| Dampening time | <1 minute |
| Class | LLOYDS, Code for lifting appliances in a Maritime Environment (LAME) |