As a result of rapidly increasing demand for large-sized ships, ship launching in today's shipbuilding is a problem that requires deliberate consideration for increased launching weight. In the shipyard to which the writers belong, 4 large-sized ships, the biggest of which was an ore or oil carrier of 21,360 tons launching weight, were successfully launched in 1963 on 4 lines-slipway combined with 3 ways of 3'-0", 4'-6" and 6'-0" breadth. The most serious problem on the 4 lines-slipway is how to distribute launching weight evenly on each standing way. A special attention was paid to set 4 lines standing ways on the same surface as designed and to keep fat and soap in proper condition just before launching. As the maximum allowable pressure on fat is experientially considered to be about 20 tons/cm^2 mean, the mean pressure in case of the above 4 lines-slipway was kept within this limit. The sliding way was composed of 2 main ways and 2 additional sub-ways which were connected flexibly by means of tie bolts at forward and after parts and through-blocks inserted in way of forward and after poppets and triggers. Advantages gained by the adoption of 4 lines-slipway are: 1. Cost for making and maintaining wider ways and blocks (over 6'-0") can be saved. 2. With a combination of 3 kinds of conventional ways of 3'-0", 4'-6" and 6'-0" breadth, large-sized ships up to 130,000 deadweight tonner can be launched. Also, launching preparation works can be proceeded at 2 building berthes in parallel up to 70,000 deadweight tons.
抄録全体を表示