Launching of floating substructures

Tugdock Submersible Platforms (TSPs) are road transportable and can be assembled in any combination of 5m x 5m deck sizes up to 120m x 120m (394ft x 394ft). They can be used for loadout operations, or to assemble on top and then launch steel or concrete structures such as Floating Offshore Wind Turbines. 

The TSP is a versatile vessel/structure and can be used for various projects, including those that require: 

1. Floating load bearing platform 

2. Fixed (grounded) load bearing platform 

3. Ability to submerge to allow float-off or float-on operations during launching or recovery.

A floating TSP can operate in water depths of less than 3 meters (10 ft) when unladen. 

A floating TSP can operate in water depths of less than 6 meters (19.7 ft) when fully loaded with Payloads of up to 20,000 metric tons. 

A grounded TSP is able to support the high loads typically associated with construction and decommissioning projects within industries such as Floating Offshore Wind (FOW) and Oil & Gas. 

A grounded TSP can operate in locations where ground bearing capacities may typically be considered low. This is achieved by using a combination of mudmats (capable of spreading load over a large area) and also by taking advantage of the TSP variable buoyancy, which if required, can be increased at low tide conditions to reduce ground pressures, and reduced at high tide conditions to ensure the platform does not lift. 

The grounding, floating and submerging capabilities of the TSP, allow operations to be carried out on a static (grounded) platform which can then be floated, while supporting a large Payload, relocated to an alternative location if required, or can be fully submerged in deeper water to allow the Payload to be launched (ie float-off). A similar method can be used in reverse to retrieve a floating structure/vessel. 

Multiple TSPs can be grounded adjacent to one another to provide a large, stable, working platform, with a plan area to suit any project, that can be rearranged, or added to if required to suit specific project requirements or future growth. 

The TSPs typically have 10 metric tons per m2 deck loading and 350 metric ton point load capability at 5 meter centers anywhere on the deck. Increased deck area loading can be achieved when required, such as for SPMT load out operations, using heavy duty deck panels with 20 metric tons per m2 deck loading. 

When required, increased capacity deck and frame members may also be utilised. 

Buoyancy and stability of the TSP is provided by utilizing a number of Buoyancy Air Bags. Buoyancy loads from the air bags push upwards on the underside of deck panels. The air bags are inflated by air compressors with hoses attached to valves at the top of the bags. 

The TSP may be partially or fully grounded on the seabed when fully loaded either to provide additional stability to reduce motions for complex operations such as skidding load-outs, or WTG integration using cranes.