DROMEC Winches develops umbilical winch for Seatools

Seatools is a subsea technology company that provides high-end solutions for a wide range of underwater challenges. The majority of solutions they deliver are custom-made and cater to markets ranging from aquaculture to offshore oil and gas. DROMEC Winches has developed a special umbilical winch for Seatools.

Umbilical Winch

The depth of the sea is a determining factor for placing offshore wind turbines. Foundations are realized by driving so-called pile casings into the seabed, which generates significant vibrations that can disrupt marine life. These vibrations need to be minimized as much as possible. Using a specially developed bubble curtain, where air is blown into the water through holes, the vibrations are dampened. To supply air to the system, a 150-meter-long hose is extended from the sea vessel. DROMEC Winches has developed an umbilical winch for this application.

Constant Tension

As the bubble curtain descends to the seabed, the electric umbilical winch automatically pays out the hose using Constant Tension. This CT function monitors the preset maximum allowable tension on the hose, thereby preventing damage. With a pulling force of 1500 kg and a hose width of 90 mm, it is a relatively large system. In this project, DROMEC also provided special controls so that the client can remotely operate the machine. In case of unforeseen extreme weather conditions, an “hammerlug” coupling can be used to disconnect the air hose from the winch and float it overboard. Additionally, the winch is equipped with a spooling mechanism to ensure the hose is neatly wound on the drum. An additional spool guide prevents damage to the umbilical hose. The entire system is compactly built within a shipping container frame, making it easy to transport and relocate during offshore operations.

Paul, engineer, says,
“Seatools is a great company, and there is much appreciation for their quality and expertise. DROMEC Winches aligns well with Seatools in terms of mentality, engineering, controls, and assembly, making it a pleasant collaboration!”

DROMEC builds series of Pull-In Systems

Van Oord is a leader in offshore wind farm construction. The company is responsible for the cable pull-in operation for the Sofia Offshore Wind Farm project located on the Doggersbank in the North Sea. This operation involves providing the wind turbine with power cables to transport the generated energy. In 2019, DROMEC delivered a special series of 10 user-friendly pull-in systems for this application and is now supplying another series of 10 systems.

Stefan Graat, Project Engineer at Van Oord:
“Dromec provides Van Oord Offshore Wind with equipment, support, and services that make a significant contribution to successful cable projects!”

Pull-In System

The pull-in system, developed specifically by DROMEC, is used to draw the thick power cable from the ship into the wind turbine. It is a complex tool designed for this purpose. Specific variants have been designed for different continental areas. For instance, in the waters of the United Kingdom, additional safety standards are required, such as LOLER and PUWER.

Constant Tension

Before installing the wind turbine on the platform, the pull-in operation takes place. The cables are pulled from the ship through the seabed into the platform using the DROMEC pull-in system. This system features a constant tension function, ensuring that the cable is always kept at a preset tension, even when unexpected changes in cable force occur. This prevents cable overload. This special tool has a nominal pulling force of 10 tons, which is maintained through friction between the rope and a special capstan head. The combination of the number of wraps and a fairlead ensures the safety of the pulling force up to a holding force of 12 tons.

Pieter, engineer DROMEC:
“We designed this compact pull-in system specifically for operations of this kind, and since then, the demand from various customers has significantly increased. It’s a user-friendly tool that can be installed for any pull-in operation on a random platform. The combination of its low weight and high force, along with advanced control software, provides real time savings for the customer. The system can be used both in a standing and hanging configuration. Various improvements have been made for the new series, such as the nominal pulling force and the hard-anodized capstan head. This material is more resistant to corrosion. The frame is also more user-friendly with an integrated lifting eye and an additional guide bracket, allowing the cable to wind on and off at a 70-degree angle.”

Automatic Tensioning

The system operates with automatic tensioning. A fairlead that runs in sync with the capstan head through the control system ensures a consistent tension between the fairlead and the capstan, guaranteeing the pulling force by the capstan without the need for a person to hold the loose end continuously. The system is electrically powered, compact, and lightweight, weighing 550 kg. It weighs 475 kg without the detachable fairlead. Once the operation is complete, the system is moved to the next wind turbine platform.

DROMEC Service Worldwide

As the DROMEC Winches team, we take care of on-site commissioning. Our experts are the ultimate support for our customers. With their technical expertise in special winches, we can provide valuable insights in complex situations. Whether there’s a breakdown on land, at sea, or high in the sky, we’re ready to respond. And yes, we may make mistakes from time to time, but we don’t shy away from fixing them! That’s the essence of DROMEC Service worldwide!”

Special project

At this moment we are busy with the assembly of a special project, we will share more details later on.

For this system, Dromec designed a special cable pulley that is produced by our supplier Hillebrand Verspaning Middelburg. This pully has a diameter of ø1600 mm and is suitable for a ø 86 mm cable. Weight is 1200 kg!

Nice piece of metalworking!

Working together on a safe and effective working environment. It’s the absolute team effort !

From small winch to complex custom solutions. Our team is specialized and certified and has gained an enormous amount of experience.

DROMEC winches. Your movement in good hands.

Dynamic and Innovative in winches, winchsystems, controls and software. With our enthousiastic team, we develop  from small till  very big & complex systems with the highest demands in terms of safety and ease of use. We also work very closely with certified body’s as DNVGL, BV, ABS, Lloyds so your winches and systems can be completely certified at our own company together with you.

It often starts with a good idea, preferably on a piece of scrap paper. After an initial consultation, we prepare one or more proposals, including a target price and preliminary drawing. Your idea or problem, always remains central in this. If the feeling on both sides is good, we start. Thanks to our own inhouse developed and written project software, your project stays in the picture and under control from start to finish, including the planning and delivery time. We are LloydsRegister ISO 9001 certified.