AB Hagglund and Soner, Swedish manufacturer of hydraulic motors and deck machinery, is one of the world's leading suppliers of marine cargo deck cranes. Represented in the United States by Stal-Laval, Inc., Elmsford, N.Y., the Hagglund crane has become known as the U.S. crane—all Hagglund marine cargo cranes installed on ships built in the United States in the last 10 years have been contracted, installed, and serviced by Stal-Laval. A variety of crane types, including single, twin, team, and grab, as well as ice class, are now operational on American-built ships. More than 1,200 ships worldwide have been equipped with deck cranes by Hagglunds. The company has a continuing development program resulting in new designs and practical solutions to unique cargo problems.
The weakest link in the Arctic cargo handling chain is the stevedore. Human beings experience serious trouble when temperatures fall much below —25° C, or sooner if it is windy as well as cold. Some type of unit load handled by automatic cargo handling equipment is therefore a prerequisite for efficient cargo handling in the Arctic. Hagglunds manufacturing methods, quality control, materials, etc., make it possible to use standard deck cranes at temperatures down to —25° C, or down to —30° C with extra heating and different hydraulic oil. Hagglunds experts have the know-how and the experience of cargo handling in Arctic climate, enabling them to offer cranes and cargo handling equipment suited to operation at temperatures of —40° C or even lower. Hagglunds tests all new hydraulic crane components under winter conditions to determine reliability at low temperatures.
It may seem that a special product like an Arctic crane is manufactured only in small numbers, but this is disputed by one of Hagglunds biggest orders. On December 12, 1980, Wartsila's Turku Shipyard in Finland gave an order to Hagglunds' deck machinery division confirming the yard's intention to cooperate with AB Hagglund and Soner in a major new building project consisting of nine ships designed for polar conditions. The order calls for 45 cranes to be delivered between December 1981 and December 1982.
Another indication of Hagglunds' continuing concern for quality in its products is its research into the optimum design for crane bases.
Simple cylindrical bases give rise to design problems which may be difficult to solve with conventional strength calculations. A further difficulty arises in the case of combined cylindrical/tapered cone bases in the determination of the stress which can arise at the transition between the cylindrical and tapered parts. The third type of base is the rectangular kind. Design calculations are analogous to those for cylindrical tapered bases, which means that the diaphragm stresses generated by the crane tilting moment are not greatest around the crane axes of inertia. The most difficult type of base from all points of view is the side-located. This base presents all the problems encountered with the others, plus a few more. It is a challenging engineering problem involving FEM (Finite Element Method) of stress analysis for each individual case. A number of these special crane mounts are now in successful operation.
Another recent product resulting from research is the Team Crane®, a further development of the twin crane. In this newest system, two cranes are electrically interconnected and synchronized automatically, enabling operation "in team." The Norwegian Knutson Line is the owner of the Maria Bakke, which calls on U.S. West Coast ports with a "team" of 4 x TG2524 Hagglund cranes. Total lift capacity of these cranes is 100-ton with a single crane driver controlling the "team" as one machine. The installation of the Team Cranes results in a vessel being entirely independent of shore cranes to load or unload. Hagglund can provide a lift capacity of 240 tons by the installation of four of its 60-ton cranes. Units supplied as Twin Cranes may also be interconnected for team operation.
For more information and specifications on the full range of Hagglund hydraulic motors and deck machinery,
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