River-sea tug-barge trains and composite vessels for work from Dnepr ports towards marine transshipment complexes and ports
On 20-21 of October, 2015 the XVIII International Transport and Logistic Conference took part in Odessa. The Conference was organized in the boundaries of Measures Plan of Black Sea Economic Cooperation Organization for the second half of 2015; its name was: "Ukrainian Market of the Transport Service Development in the conditions of integration into European and International transport systems".
Representatives of a number of organizations participated in the conference workout, as follows: Ministry of Infrastructure of Ukraine, International Association of Black Sea Shipowners, Association of Black Sea and Azov Sea ports, Federation of Employer of Ukrainian Transport, Association of Ukrainian Shipbuilders "UkrSudProm", Institute of Electro Welding named after E.O.Paton, domestic and foreign shipping companies, manufactories of vessel's equipment and many others.
Specialists of Marine Engineering Bureau introduced report "River-sea tug-barge trains and composite vessels for work from Dnepr ports towards marine transshipment complexes and ports" (Authors are G.V. Egorov, A.G. Egorov).
It was emphasized in the report that there is necessity to build new composite vessels and tug-barge trains of "Dnepr Max" type that are especially effective for transportation of mass cargoes from the river ports of the Dnepr River.
For large owners of vessels or cargo, the main objective now is work from river terminals towards road transshipment complexes (RTC) and / or marine deep-water ports, i.e. actually ensuring of mass cargo delivery to the marine vessels. The source of such interest is mostly defined by lack of deep-water ports number and by difficulty of cargo delivery to these deep-water ports by rail or automobiles.
The feature of work of the scheme "river terminal - RTC" is the combination of rather big river shoulder through the internal waterways and rather small (but strong influencing) marine shoulder. An ultimate goal is loading (unloading) of the river-sea vessels (RSV) from (to) on a marine vessel of deadweight up to 300 thousand tons in the conditions of port roads (RTC) or port (STS (ship-to-ship) mode).
It is clear that overwhelming part of the used cargo vessels and pusher tugboats has considerable age and is to be replaced by new fleet in the nearest future. In turn it demands a clear idea about aims, conditions and methods of working activity for new of tug-barge trains and composite vessels.
The following operation models for tug-barge trains are actual for today used working scheme "river terminal - RTC":
• scheme on the basis of the "rotator" one that foresees pusher tugboat plus several barges for cargo transportation between ports;
• self-propelled pusher vessel plus single barge for cargo transportation from river ports towards road transshipment complex (RTC);
• pusher tugboat plus single barge for cargo transportation from river ports towards marine ports or port of other river basin or RTC;
• pusher tugboat plus two barges cargo transportation from river ports towards RTC.
It is possible to recommend providing of some all-design decisions, namely optimum assignment of class for the sailing region that will allow light weight minimizing; the greatest possible block coefficient due to actual operating conditions, that will allow to increase the loading capacity of train vessel; universality, i.e. barge must to be able to work with the marine ("new") pusher-tugs such as with the existing river pusher-tugs. It is desirable to provide economy of running time due to passing all the route without composite vessel rearrangement, accepting all available composite vessel's dimensions in accordance with navigation rules and keeping manoeuvrability due to way conditions of the river basin appointed by the requirements specification.
Vessel with the maximal available block coefficient for the set speed range is mostly effective for mixed cargo transportation at the field of today river and river-sea transportation of the mass cargo. For the speed range of 8.5 - 10.0 kn (the main range for existing RSV) block coefficient of 0.93 is mostly effective; the bigger value of bock coefficient induces sharp increase of towing resistance and consequently fuel expenses; the smaller value of bock coefficient leads to less capacity of the carried cargo and consequently to the worse economical rates while same port and different navigational expenses (passing through locks or under bridges).
The concept of the composite "Dnepr Max" looks as the most realized. "Rotator scheme" and tug-barge trains concept in a whole demands the guaranteed constant cargo flows with the developed logistic chain; but now that is problematic.