Safe debris disposal at sea

The automated clearing platform now safely removes debris that falls onto the deck after the trailing head of a trailing suction hopper dredger has been caught. A dozer blade pushes the debris overboard. The dozer blade is driven by the Tecdos Pi-Gamma 2-in-1 chain drive system from RUD Ketten Rieger & Dietz. Van Oord won the IADC Safety Award 2018 from the International Association of Dredging Companies with the newly designed scraper system.

Van Oord is a global player in the maritime contracting sector and one of the world's leading companies in the industry. With projects such as the dredging of the Suez Canal or the construction of the Palm Islands in Dubai, the Dutch family business has become world-famous. The global player is also active in offshore wind and offshore infrastructure projects. Van Oord uses its ship Vox Amalia, a trailing suction hopper dredger, to build and expand port infrastructure and to reinforce coastlines.

A plus in occupational safety on the ship

During dredging work, debris can fill the trailing suction hopper dredger's suction head. When the suction pipe is brought back on board, the debris that got stuck in the trailing head falls onto the deck. This debris can range from large boulders to sticky clay and must be removed from the ship. The clearing platform has been performing this task since 2020. The aim when developing the platform was to increase safety for the employees on the ship. A bulldozer blade driven by RUD Tecdos chains pushes the debris back into the sea at the push of a button. The Vox Amalia is the first ship in the Van Oord fleet to be equipped with the innovative scraper system.

"With the debris clearance platform, we have found a safe and effective way to clear our ship of debris," says Maarten van Duijn, Technical Superintendent at Van Oord. "This innovation has significantly reduced the risk of harm to the crew working on board. We have already taken safety into account during the design phase, so dangerous working conditions during operation have been eliminated or significantly reduced. This is the most effective way of controlling risk."

Tecdos-Pi-Gamma: the 2-in-1 chain drive system

The dozer blade on the Vox Amalia is moved by the innovative Tecdos-Pi-Gamma drive system from RUD. The 2-in-1 chain drive system was specially developed for vertical and horizontal applications and has a chain wrap of between 90° and 180°. It is in use on the Vox Amalia at Van Oord with a chain deflection of 180°. The Tecdos drive system installed there can withstand loads of up to 13 tons. "In principle, the drive system used at Van Oord is a standard application," explains Heribert Herzog, design engineer and application engineer in the Conveying and Driving division at RUD. "With 14 teeth, the sprocket is slightly larger than usual, as the distance between the chains was dictated by the attachment option on the dozer blade and had to be increased accordingly."

Robust components for offshore use

The Tecdos Pi Gamma drive system is based on a high-performance round steel chain. This runs over a drive shaft that is free of additional forces. For maritime use at Van Oord, both the round steel chain and the sprockets are made of case-hardened steel. "When used in the maritime and offshore sector, the robustness of the drive system is the decisive criterion par excellence. This is because wind, salt water and sand place particularly high demands on the components and they have to successfully withstand these maritime challenges," explains Herzog. "The drive system of the clearing platform must not be allowed to fail," Herzog continues.

RUD has been working with Van Oord for 23 years. The 2-in-1 chain drive system Tecdos-Pi-Gamma from RUD is a particularly robust and corrosion-resistant chain drive made from case-hardened steel, making it perfect for use at sea and on the coast. (Sabrina Deininger)

The article appeared in materialfluss 10/22.