We had EPCI (engineering, procurement, construction & installation) experiences in supply of large offshore equipment and structures. We are proficient in providing the creative, cost-effective and comprehensive engineering solutions. We keep improving our technologies to fit for future sustainable development. Click here to download a brief introduction.
Jack-up Leg Cushion System
Offshore wind turbine installation relies on purpose-built jack-up vessels, which will move from one site to another for installing the turbines. Such a move involves the jack-up leg handling operations, and can only be done in very benign weather conditions due to the impact load between the leg and seabed. This significantly affects the workability or productivity of the jack-up vessels.
We are developing a mechanical cushion system, to be affixed to the bottom of jack-up legs and able to damp the impact load when leg touching down. Hydraulic cylinders are used as the dampers, and they are enclosed in a watertight space inside the spudcans. Side loads on spudcan and sand-ingression damage to mechanical parts have been well considered. With this system, the annual workable days of a WTIV can be increased by typically 50 to 75 days.
Floating Turbine In-situ Large Component Exchange
Large Component Exchange (LCE) is an essential issue in O&M of Floating Offshore Wind Turbines (FOWT). Components of future FOWT can be well above 250t. Due to lack of capable equipment, the only viable solution nowadays is to tow the complete FOWT back to a service port or sheltered water, and do the LCE with a crane on the quayside or a jack-up.
We have developed and patented a method to complete the LCE on-site, with a land-based crawler crane onboard the FOWT floater. No change for the turbines, but a temporary working platform on the floater. Our technology enables the safe transfer of the crawler crane from a transport vessel or SOV to the FOWT floater. All equipment involved can be repeatedly used for similar type of FOWTs. We are in discussions with wind farm operators, turbine manufacturers and research institutes to promote this technology.
Floating Turbine Alternative Mooring Method
Floating Offshore Wind Turbines (FOWT) are difficult and expensive to moor. Current industry practice is to keep FOWT in place by several/spread mooring lines, and each FOWT unit would consume thousands of tons of mooring chains. This is not only costly, but also creates another supply chain bottleneck in Europe.
Based on our experience in FPSO, we are developing an alternative solution for FOWT – Single Anchor Mooring. Instead of using multiple mooring legs to the floater, only one mooring leg will be used. Beside the huge cost reduction (75%) on the mooring system, the single anchor minimizes the seabed coverage and interference with existing infrastructure. The anchor can be of gravity type and made of concrete. In addition, the floater can be made streamlined to maximize the weathervane benefit. We are progressing towards a model basin test in this year.
Mooring Turret and Chain Stopper Design
For the mooring of floating offshore wind turbines (FOWT), the chain connector or stopper at fairlead shall be of pull-through type and allow quick connection and disconnection. The OPB-induced fatigue needs careful evaluation especially due to its non-redundant mooring line arrangement.
We have experience in the chain stopper design for FPSO mooring, which is similar to FOWT. We can do a quick fatigue analysis for the mooring chain top connection, and have a chain stopper solution characterized by its double articulation, pull-through and full-welded design.
Offshore Heavy Lift Crane
We had EPCI experience in supply of offshore heavy lift cranes, and participated in the engineering processes of cranes from 500t up to 5000t. We are familiar with DNV, ABS, API, LRS and Norsok requirements.
We are particularly proficient in quick concept design and budget estimation, with know-hows on designing a light boom and robust slew bearing supports. We can also write various project documents for clients, including crane technical spec, basis of design, material spec, fabrication spec, assembly procedures, and operation manual.
We have an efficient approach for an add-on heave compensation system.
Deepwater Pipelay Stinger
For the heavy lift vessels used in the offshore oil industry, a pipelay system, of either S-lay, J-lay or reel-lay, is often a standard add-on. We had been involved in a basic design of a 90m long S-lay stinger, and concluded a design methodology which can speed up the iterations among mechanical, structural and hydrodynamic analyses.
The stinger consisted of 3 sections, and could be assembled into 3 different lengths, using the heavy lift crane onboard vessel. There were several design philosophies developed during the design, like roller-box position, compact member section, non-eccentricity at joints, etc. The resulted stinger weight reduction, comparing with similar designs of peers, was around 40%.
Telescopic Gangway (Walk-to-Work Bridge)
We had been involved in an EPCI project for a 36m long telescopic gangway, and solved the major technical challenges in the design. Combined with our knowledge in offshore cranes, we can provide you with the best solution for offshore personnel transfer.
Motion compensated walk-to-work bridge becomes a standard for offshore wind maintenance using a SOV (Service Operation Vessel). For personnel transfer between a work boat and a fixed platform in high seas, we have a solution called boat lift, which will lift the boat out of water with a bridge structure rotatably mounted on the platform.