Research On The Port Tugboat Marshaling

With the growth of the world trade amount and the development of the port operation, freight-shipping expands to large-bulk. Specially, more and more bulk shipping are used for staple freights ocean-shipping. And market competition becomes sharp day and day after our country entered WTO. To Tianjin Port, shipping putting in also becomes bulky, along with the extension and rebuilding of deep-water port-lane and wharf, and with the standing increase of the shipping's load. Whether or not a port has capacity of lading and unloading in large quantity, and whether or not a port can ensure shipping putting in or leaving in time directly influence the competition and economic benefit of the port.Shipping putting in or leaving a port needs tugboat to tow. Because putting in or leaving a port is a stochastic and discrete matter (shipping 's size, load and the time of putting in or leaving a port are all stochastic), there is definite difficulty in tugboat's marshaling. One side, the difficulty maybe lengthen towing-time for which the shipping must wait; the other side, the difficulty may low the tugboat's utilization ratio, which wastes the port's resource. So it is real significant for suiting the development of the port to study the optimization of the tugboat marshaling in reason and bring forward a reasonable project on tugboat number and horsepower distribution.Based on analyzing the tugboat's marshaling mode and operation status in Tianjin Port, this article put forward present questions of tugboat marshaling, used statistical data and computer simulation means to simulate the process of the tugboat operation, and provided consult basis for decision-making which was based on the different running results of the respective tugboat marshaling projects. Meanwhile, the increase of throughout and the trend of bulk shipping putting in or leaving Tianjin Port were analyzed. Then the article detailed analyzed the following questions through jointing the tugboat marshaling and the port operation:1. Analyzing the tugboats' number and horsepower marshaling mode in Tianjin Port, based on the development of throughout in 2005 (which may be 140millions ton) and the requirement of 150,000-ton-shipping putting in and leaving the port;2. How to organize the marshaling structure of tugboat-fleet to adjust the requirement in 2010, when the throughout of Tianjin Port will come to 200 millions ton;3. Studying the change of the tugboat utilization ratio and the influence of the whole layout of tugboat-fleet, in accordance with the change which shipping putting in or leaving the port will be random and needn't concrete operation, along with widening the port-lane and allowing the two-way shipping.