The Dutch dredging industry has an exceptionally good reputation, both nationally and internationally. That’s not too surprising, since the Dutch have a history of coming up with reliable solutions for complex problems when it comes to water management and dredging.
The requirements that this industry places on its equipment are extraordinarily high. Imbema Cleton’s specialists were therefore approached by a renowned Dutch dredging firm to develop a new design of dredging hose to meet the stringent requirements for special use on a unique dredging project.
In a project being undertaken by this dredging firm, sand is sucked up from a river bed in order to create extra channels. This increases the width of the river when the water level is high and reduces the risk of flooding.
The sand is sucked up and then deposited in an enormous hopper of a special ground compaction unit.
A 10″ (250 mm) diameter hose is connected to one side for the water feed and a 12″ (300 mm) diameter hose is connected on the other side to discharge the mud/sand mix. The 12″ hose, in particular, has to endure a great deal. The inside of this hose is subject to a severe amount of wear due to the abrasive effect of the sand.
The tensile forces are immense because the interconnected hoses are pulled along over land.
The connecting flanges between these hoses also have a tendency to dig into the ground as they are being dragged across it. With these problems in mind, in addition to a range of exceptional requirements, Imbema Cleton developed a durable and reliable solution by working in collaboration with the engineers at the Italian manufacturing partner IVG. IVG’s Murray/RV type hose was used as the basis for the new design. This hose was pre-cut to a length of 11.8 m so that it fitted exactly into a 40-foot container. Thick reinforcements were applied on the outside of the hose at the position of the Victaulic vulcanised couplings so that the outside diameter was wider than that of the couplings.
These prevent the hoses from burying and anchoring themselves into the ground when being dragged along.
A white layer is incorporated in the very wear-resistant hose to act as a wear indicator that provides early warning that the hose is ready to be replaced. The Dutch dredging firm specified exceptional requirements for the tensile force that the hose has to be able to withstand. For example, the water hose has to be able to tolerate a full 8 tons (= 8000 kgf or approx. 79 kN). A requirement of no less than 14 tons (= 14000 kgf or almost 138 kN) was specified for the wear-resistant hose used for transporting the sand. The prototype of the wear-resistant hose managed to easily exceed 16 tons, thus more than meeting the client’s requirements: 16 tons equals the weight of 11 large mid-range cars. Convinced of this reliable and durable solution, the dredging firm bought these newly developed hoses from us and is now using them for the project, to their complete satisfaction.