Lightweight tool for unsafe depths - Frahm sediment sampler

Tags: dredging ocean science

MBT, MacArtney Germany, supplies equipment for sampling the surface sedimentation.

The Frahm sediment sampler is a special device for fine sand testing at sea, in ports or in inland waters. It combines features like a small, compact height and a low weight with high efficiency and is thus suitable for smaller boat applications in shallow water areas.

The sediment sampler was developed by Andreas Frahm of the Leibniz Institute for Baltic Sea Research Warnemünde (IOW). In 2012, application for a patent was submitted and the production outsourced to MBT GmbH, MacArtney Germany, Kiel, which manufactures and distributes the equipment.

With the Frahm sediment sampler, short cores of up to 80, 100, and also 120 cm in length can be "pulled". Thus, the technology closes a gap between multicorer and gravity. The gravity consists of one single steel tube, which goes to water depths down to 18 m through the massive sediment by means of weights made from massive lead disks. For the investigation of the upper sediment layer including soil water, multicorers (MUC) are used.

Assuming that the cores of the MUC have a maximum length of 40 cm, a range of up to 20 cm is always lost in this type of sampling. It is precisely the complete overlap that is important for continuous historical reconstruction. The quality of the specimens has been increased by a longer spike (up to 1 m) with a larger diameter (10 cm) and the previously unsafe depth is now covered by a core. The weights being arranged appropriately, sampling of the soil water is also possible.

The greatest advantage, however, lies in the uncomplicated handling of the Frahm sediment sampler. With a weight of 36 kg and the slim shape two persons will be able to operate it from a boat with small bars and winches. Therefore, sediment tests are possible in shallow water areas, in port basins or river streams which are otherwise difficult to access. Likewise, this unit is available to expert activities by private engineering companies.

The development of the Frahm sediment sampler entails several advantages. On more than ten expeditions by the IOW geologists on the large German research vessels into the Chinese Sea it has become a standard instrument. Thus, a wider customer portfolio has appeared in relation to the Frahm sediment sampler far beyond pure marine geology. In addition, owing to its efficient and economical design, the sediment sampler represents a price segment being far below the solutions so far available in the market.

For further information please contact Andreas Reikowski.