Engineering
Each drilling project has its own characteristics
With our expertise, we can find the best solution for your project. Our engineering department has solved many environmental challenging subjects. DDC can provide complete drill strings or the specific components you require. We also offer advice and can provide spare part package for your drill rig.
Discharge Treatment
In the event when discharge cannot be deposited directly on land or in the water, we can provide settlement systems:
– Open system (clean water flows freely away)
– Closed system (clean water is reused)
Drive, Drill, Drive (3D Method)
This installation method uses a combination of a drill rig and hammer. The pile is hammered until refusal, then drilled and finally hammered again to the target depth. With this method, you don’t have to use a temporary casing or grout and you can reduce the size of hammer. This saves time and cost.
Underreaming
DDC has several types of underreamers in stock. The underreamer can be standalone or integrated into the drill bit, and they are either pneumatic or hydraulic driven. DCC also can design underreamers for specific projects.
Extendible Arms
Lot of wind farm projects nowadays use monopiles of various sizes, some with a tapered design. Due to the conical shaped monopiles in the offshore wind industry, the top diameter of the monopile is smaller than the bottom diameter. In order to drill out the complete inside diameter of the MP, DDC designed a BHA which can in retracted mode fit through the smaller top section then expand before drilling out the larger diameter of MP at seabed level.
Motion Compensated
DDC executed the world’s first 3D motion compensated foundation drilling. This unique setup allowed us to drill through subsea jacket foundations in a floating setup. By compensating for the 3D motions of the barge, drilling operations continued throughout the winter, irrespective of waves and swell. The Bottom Hole Assembly could be precisely lowered and positioned by the 3D compensated crawler crane, swing of the drill pipe were completely eliminated. The motion compensated drill rig made this 24/7 non-stop operation very cost efficient and above all safe!
(Wikinger)
Pile Cutting
After the lifetime of offshore structures, decommissioning becomes more and more important. The structures are (grouted) stiff in the seabed. These structures cannot be pulled out easily. DDC can drill out jacket or monopiles by using a cutting tool that is part of the drill string. This tool cuts the pile beneath the seabed, allowing the structure to be removed.
(Cutting test)