Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Tham khảo tài liệu 'lesson 7-workmanship for hull building(1)', ngoại ngữ, anh văn thương mại phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Lesson 7-Workmanship for Hull Building 1 It is really fascinating to gaze at a colossal ship standing high on a slipway or sailing fast at the blue sea and you will be still more excited if you are offered a chance to pay a visit to the wonderful labyrinth inside a ship. Indeed a ship to the mind of a naval architect is a true work of art. But few of the ordinary people have any idea about the workmanship for hull building. One might be surprised to learn that the construction of a floating little town with such complicated . hull form and such complex hull structures should start with the very paper work. To give you some brief introduction on the primary workmanship for hull building we would like to relate as follows 1. Lofting Lofting is the first workmanship for hull building and will therefore influence the quality of the following workmanship. And that s why high accuracy has to be obtained during lofting. Usually lofting is conducted on a mould loft. There are two steps here. First we must work out a projection plane in the light of geometrical principles in proportions as 1 1 1 5 or 1 10 in accordance with the given sizes indicated on drawings. Then different sorts of model plates model rods and model cases as well as sketches are to be prepared as the reference to material marking processing and fabrication. Besides lofting can be made use of to make up the shortcomings of drawings for it is impossible to mark all the shapes of members on the drawings. Furthermore no matter how careful you are when drawing a lines plan errors are inevitable in respect to hull cleanness when the plan is magnified. In this case improvement will be made upon the plan by means of lofting. With regard to the methods of lines lofting the advanced mathematical lofting is widely used nowadays which calibrates and provides lines offsets for a clean hull with the help of an electronic computer. 2. Material Marking The exact meaning of material marking is to draw an expansion of a .
