36-Ton Telescopic Overhead Traveling Crane
Marine transport today is undergoing a major change in the make-up of main cargo categories from raw materials to semi-finished and finished products, but whatever is to be carried, shippers' foremost qualitative priority is given to the punctuality of transport.
There are fleets of multipurpose cargoships trading between the United States, Canada, Japan and Europe, carrying forest products including newsprint rolls, sawn wood for housing use, typically for two-by-four structures, pulp, together with steel coils and other secondary metal products.
As these cargo items are generally vulnerable to moisture, keeping the sailing schedule without being affected by rain is a major challenge to shipping operators especially during the rainy season in Japan and in winter on the West Coast of Canada where warm currents bring frequent rains.
One solution is an all-weather type vessel, whose cargo hold section and upper deck are wholly covered by a roof-shaped superstructure like a gymnasium. A ship of this type is now under construction at Hyundai Mipo shipyard in Korea to the order of a major Norwegian shipowner.
The vessel's cargo handling system consists of two 36-ton overhead cranes, which can travel inside the all-weather roof from bow to stern, and two side port doors in two broadside positions for letting cargoes in and out. The 17-m wide side port doors can be opened upward to serve as roofs, and curtains hanging on their three sides serve as walls to facilitate safe cargo handling in the rain.
Tsuji Heavy Industries Co., Ltd. has been awarded an order for the vessel's cargo gear system which constitutes the core of its cargo handling functions, and will manufacture and deliver two sets each of the overhead crane and side port door.
Main particulars of the overhead cranes are as follows.
Main Particulars
・Type: Onboard telescopic overhead travelling crane
・Quantity: 2 pcs per ship
・Usage: 20ft & 40ft container
Paper rols, pulp bales, aluminium ingot, steel coil and packed lumber
・Rated load: 36 ton (under turntable)
・Hoisting speed: 45m/min. (with rated load 36 ton)
90m/min. (with load 15-0 ton)
・Lowering speed: 55m/min. (with rated load 36 ton)
90m/min. (with load 15-0 ton)
・Operating/cycle: 25 cycles/hrs, 20-24 hrs/day, 7 days a week, each 9 days for minimum 25 years
・Trolley travelling speed: 50m/min, against 5 degr. list and 2 degr. trim
・Telescope speed: 50m/min, against 5 degr. list and 2 degr. trim
・Gantry travelling speod: 50m/min, against 2 degr.trim
・Turntable slewing speed: 15 sec. per 90 degr.
・Hoisting lift: Abt. 20m total.
Above coaming abt. 5.3m.
Below coaming abt. 14m.
・Outreach: 7.5m from ship side
・Rail span: Approx. 21m
・Cargo positioning: Center of turntable/lower pulley shall be able to reach distance 830mm from longitudinal bulkhead when vessel in even keel.
・Crane travel distance: 94.815m
