Lesson fifteen Lines Plan and Fairing, Fabrication and assembly The lines plan; fairing A lines plan, usually a 1/48 lifesize scale drawing of a ship, is used by designers to calculate quired hydrostatic, stability, and capacity conditions. Full-scale drawings formerly were obtained from the lines plan by redrawing it full size and preparing a platform of boards called a scrive board"showing the length and shape of all frames and beams. Wood tem plates were then prepared from the scrive board and steel plates marked off and cut to size An alternative to the full-scale scrive board is a photographic method of marking off, introduced about 1950 and widely adopted. The lines plan is drawn and faired(mathematically delineated to produce a smooth hull free from bumps or discontinuities) to a scale of one-tenth full-size by draftsmen using special equipment and magnifying spectacles. The formerly prepared drawing, generally on one-tenth scale. Photographic transparencies of these drawings are then projected full size from a point overhead onto the actual steel plate. The plate is then marked off to show the details of construction, such as position of stiffening members, brackets, and so on. This optical marking off system is much more economical in terms of space and skilled labour than the older method By the 1960s, digital computers were being used to fair the preliminary lings plan by a numerical method. Faired surfaces can be produced to a specified degree of accuracy and the lines can be drawn by a numerically controlled drawing machine, bringing the process under continuous scrutiny. Tapes can be produced for use in numerically controlled plated-burning machines, which cut plates to shape, and for the automatic cold bending of frames and curved girders, Fairing culations produce data that can be fed back into a computer, and programmed to generate hydrostatic and stability data and other information Fabrication and assembly Since 1930, riveting has been progressively supplanted by welding. This has proved more than a mere alteration in the method of connecting structural components because welding facilitates prefabrication of large component parts of the main hull structure Before welding came into wide-scale user every ship was constructed on the building berth The keel was laid, floors laid in place, frames or ribs erected, beams hung from the frames, and this skeleton, framed structure was held together by long pieces of wood called ribbands. Plating was then added and all the parts of the structure were riveted together. In other words, the ship was built from the keel upwa The modern method is to construct large parts of the hull, for example, the complete bow and stern. Each of these parts is built up from subassemblies or component parts, which are then welded together to form the complete bow or stern. These sections of the ship are manufactured under cover in large sheds, generally at some distance from the building berth, before being transported to the berth and there fitted into place and welded to adjacent section. The advantages of this procedure are that work can proceed under cover, unhampered by bad weather, and the units or component parts can be built up in sequences to suit the welding operations-not al ways possible at the building berth itself. A number of techniques can be used to welded together two pieces of the same metallic material. The ideal weld is continuity of homogeneous material, with the same composition and the same physical properties as the parts being jointed. In steel shipbuilding, metal are welding is
Lesson Fifteen Lines Plan and Fairing, Fabrication and Assembly The lines plan; fairing A lines plan, usually a 1/48 lifesize scale drawing of a ship, is used by designers to calculate required hydrostatic, stability, and capacity conditions. Full-scale drawings formerly were obtained from the lines plan by redrawing it full size and preparing a platform of boards called a “scrive board” showing the length and shape of all frames and beams. Wood tem plates were then prepared from the scrive board and steel plates marked off and cut to size. An alternative to the full-scale scrive board is a photographic method of marking off, introduced about 1950 and widely adopted. The lines plan is drawn and faired (mathematically delineated to produce a smooth hull free from bumps or discontinuities) to a scale of one-tenth full-size by draftsmen using special equipment and magnifying spectacles. The formerly prepared drawing, generally on one-tenth scale. Photographic transparencies of these drawings are then projected full size from a point overhead onto the actual steel plate. The plate is then marked off to show the details of construction, such as position of stiffening members, brackets, and so on. This optical marking off system is much more economical in terms of space and skilled labour than the older method. By the 1960s, digital computers were being used to fair the preliminary lings plan by a numerical method. Faired surfaces can be produced to a specified degree of accuracy and the lines can be drawn by a numerically controlled drawing machine, bringing the process under continuous scrutiny. Tapes can be produced for use in numerically controlled plated-burning machines, which cut plates to shape, and for the automatic cold bending of frames and curved girders, Fairing calculations produce data that can be fed back into a computer, and programmed to generate hydrostatic and stability data and other information. Fabrication and assembly Since 1930, riveting has been progressively supplanted by welding. This has proved more than a mere alteration in the method of connecting structural components because welding facilitates prefabrication of large component parts of the main hull structure. Before welding came into wide-scale user every ship was constructed on the building berth . The keel was laid, floors laid in place, frames or ribs erected, beams hung from the frames, and this skeleton, framed structure was held together by long pieces of wood called ribbands. Plating was then added and all the parts of the structure were riveted together. In other words, the ship was built from the keel upward. The modern method is to construct large parts of the hull, for example, the complete bow and stern. Each of these parts is built up from subassemblies or component parts, which are then welded together to form the complete bow or stern. These sections of the ship are manufactured under cover in large sheds, generally at some distance from the building berth, before being transported to the berth and there fitted into place and welded to adjacent section. The advantages of this procedure are that work can proceed under cover, unhampered by bad weather, and the units or component parts can be built up in sequences to suit the welding operations-not always possible at the building berth itself. A number of techniques can be used to welded together two pieces of the same metallic material. The ideal weld is continuity of homogeneous material, with the same composition and the same physical properties as the parts being jointed. In steel shipbuilding, metal are welding is
produced by an electric arc formed between the parts to be jointed; the fusion material is supplied by a coated electrode. The welding electrode consists of a core rod that is deposited as weld metal it is flux coated to protect the molten metal from the atmosphere during deposition and to supply cal propertie at deal of research has gone into the specific duties. The main advantages of welding over riveting are: (1)a lighter structure(because overlaps are eliminated ),(2)improved water-tightness and oiltightness, (3)smoother surfaces, and(4) reduced hull upkeep. Certain precautions, however, are necessary. The design of the structure must be adapted for welding because structural details which can be riveted are seldom suitable for welding. The joints must be carefully prepared beforehand for welding. Incomplete penetration, lack of fusion, porosity, and cracking are typical weld defects that must be avoided Hard sports must be avoided and gradual tapering off of stiffness is necessary if defects in service are to be minimized ( From"Encyclopedia Britannica", VoL 16. 1980) Technical Terms 1. fairing光顺 23. subassembly部件 2. lifesize实物大小 24 unhappen无阻碍 3. capacity condition装载状态 25. ideal weld理想接头 4.ful- scale drawing实尺图 26. metallic material金属材料 5. scribe board型线刻划台 27. homogenous material匀质材料 6. template样板,导管架 28 metal arc welding金属电弧焊 7. alternative代替方案(物)交替的 29. electric arc 电弧 8. photographic method of marking off照30. fusion material熔化材料 相号料法 31 coated electrode药批焊条 9.bump凹凸不平 32. core rod芯棒 10. draftsman绘图员 33. deposit熔敷、沉积 11. magnifying spectacles放大镜 34.fux焊剂 12. transparency投影底片 35. molten metal熔化金属 13. optical marking off光学号料 大气 14. faired surface光顺表面 37 metallurgical property治金性能 15. numerically controlled(N.C.) drawing38. upkeep保养、维护 machine数控绘图机 39. precaution注意事项、预防(措施) 16. scrutiny监视,检查 40. penetration穿透 17. plate-burning machine钢板切割机 41. lack of fusion熔深不够 18. prefabrication预装配 42. porosity气孔 19. arge component part大型分段 43. cracking裂缝 20. floor肋板 44 defect 缺陷 21.rib肋骨 45. hard 硬点 22. skeleton构架
produced by an electric arc formed between the parts to be jointed; the fusion material is supplied by a coated electrode. The welding electrode consists of a core rod that is deposited as weld metal; it is flux coated to protect the molten metal from the atmosphere during deposition and to supply certain metallurgical properties to the weld. A great deal of research has gone into the specific duties. The main advantages of welding over riveting are: （1）a lighter structure (because overlaps are eliminated ), (2) improved water-tightness and oiltightness, (3) smoother surfaces, and (4) reduced hull upkeep. Certain precautions, however, are necessary. The design of the structure must be adapted for welding because structural details which can be riveted are seldom suitable for welding. The joints must be carefully prepared beforehand for welding. Incomplete penetration, lack of fusion, porosity, and cracking are typical weld defects that must be avoided. Hard sports must be avoided and gradual tapering off of stiffness is necessary if defects in service are to be minimized. （From “Encyclopedia Britannica”, Vol. 16. 1980） Technical Terms 1. fairing 光顺 2. lifesize 实物大小 3. capacity condition 装载状态 4. full-scale drawing 实尺图 5. scribe board 型线刻划台 6. template 样板，导管架 7. alternative 代替方案（物）交替的 8. photographic method of marking off 照 相号料法 9. bump 凹凸不平 10. draftsman 绘图员 11. magnifying spectacles 放大镜 12. transparency 投影底片 13. optical marking off 光学号料 14. faired surface 光顺表面 15. numerically controlled (N. C.) drawing machine 数控绘图机 16. scrutiny 监视，检查 17. plate-burning machine 钢板切割机 18. prefabrication 预装配 19. large component part 大型分段 20. floor 肋板 21. rib 肋骨 22. skeleton 构架 23. subassembly 部件 24. unhamper 无阻碍 25. ideal weld 理想接头 26. metallic material 金属材料 27. homogenous material 匀质材料 28. metal arc welding 金属电弧焊 29. electric arc 电弧 30. fusion material 熔化材料 31. coated electrode 药批焊条 32. core rod 芯棒 33. deposit 熔敷、沉积 34. flux 焊剂 35. molten metal 熔化金属 36. atmosphere 大气 37. metallurgical property 冶金性能 38. upkeep 保养、维护 39. precaution 注意事项、预防（措施） 40. penetration 穿透 41. lack of fusion 熔深不够 42. porosity 气孔 43. cracking 裂缝 44. defect 缺陷 45. hard spot 硬点
Additional Terms and Expressions 1.ful- scale lofting实尺放样 method岛式建造法 2. Scaled lofting比例放样 tandem method半串联(一条半) 3. mathematical lofting数学放样 建造法 4. spline function样条函数 18. manual arc welding手工电弧焊 5. spline fitting样条拟合 19. submerged arc welding埋弧焊 6. shell development外板展开 20. eletroslag welding电焊渣 7.mock-up, cradle mould样箱 21. gas shielded welding气体保护焊 8. batten样条 22.one- side welding单面焊 9. nesting套料 23. tack welding定位焊 10. electropaint marking(EPM)电印号料24. fillet welding填角焊 11. block method分段建造法 25. back welding封底焊 12. subassembling部件装配 26. copper backing(CB)铜垫法 13. assembling分段装配 27. flux copper backing(FCB.)焊剂铜垫法 14. grand assembling总段装配 28. flux asbestos backing(FAB.)软垫法 15. pyramid method塔式建造法 Notes to the Text 1. scrive board型线刻划台 旧时肋骨型线用刀刻在放样台地板上,现在改用色漆。 Scrive board与现在的 loft floor 同义,可译成“样台地板”。 2. Not always possible at the building berth itself其中not修饰紧接着的副词,否定 al ways, 不是否定 possible,意为“未必总是可能的” 在含有副词或状语从句的句子中,否定式需注意分析否定的究竟是哪一部分,例: The ship did not stop operating because the fuel was finished 船舶并不因为燃油用完而停止航行 3. It is flux coated to protect the molten metal from the atmosphere during deposition and to supply certain metallurgical properties to the weld 句中的I代替前句中的 welding electrode, flux coated为表语; to protect.和 supply.两个不定式短语作目的状语用 4. The best possible coated electrodes这里best和 possible都是 coated electrodes的定语,意 为“最好的,可能存在的药皮焊条”,可译为“尽可能好的药皮焊条 5. hard spots must be avoid and gradual tapering off of stiffness is necessary if defects in service are to be minimized If引出从句中的 are to be minimized为“be+动词不定式的被动态”,在这里便是校订条 件,与if相呼应,构成条件状语从句。此句直译为:“如果要使用营运中的机械故障减到 最少,那么必须避免硬点,并且逐渐减小刚性
Additional Terms and Expressions 1. full-scale lofting 实尺放样 2. Scaled lofting 比例放样 3. mathematical lofting 数学放样 4. spline function 样条函数 5. spline fitting 样条拟合 6. shell development 外板展开 7. mock-up, cradle mould 样箱 8. batten 样条 9. nesting 套料 10. electroprint marking(E.P.M) 电印号料 11. block method 分段建造法 12. subassembling 部件装配 13. assembling 分段装配 14. grand assembling 总段装配 15. pyramid method 塔式建造法 16. island method 岛式建造法 17. semi-tandem method 半串联（一条半） 建造法 18. manual arc welding 手工电弧焊 19. submerged arc welding 埋弧焊 20. eletroslag welding 电焊渣 21. gas shielded welding 气体保护焊 22. one-side welding 单面焊 23. tack welding 定位焊 24. fillet welding 填角焊 25. back welding 封底焊 26. copper backing (C.B.) 铜垫法 27. flux copper backing (F.C.B.) 焊剂铜垫法 28. flux asbestos backing (F.A.B.) 软垫法 29. Notes to the Text 1. scrive board 型线刻划台 旧时肋骨型线用刀刻在放样台地板上，现在改用色漆。Scrive board 与现在的 loft floor 同义，可译成“样台地板”。 2．Not always possible at the building berth itself 其中 not 修饰紧接着的副词，否定 always， 不是否定 possible，意为“未必总是可能的”。 在含有副词或状语从句的句子中，否定式需注意分析否定的究竟是哪一部分，例： The ship did not stop operating because the fuel was finished. 船舶并不因为燃油用完而停止航行。 3．It is flux coated to protect the molten metal from the atmosphere during deposition and to supply certain metallurgical properties to the weld. 句中的 It 代替前句中的 welding electrode; flux coated 为表语；to protect……和 to supply……为两个不定式短语作目的状语用。 4．The best possible coated electrodes 这里 best 和 possible 都是 coated electrodes 的定语，意 为“最好的，可能存在的药皮焊条”，可译为“尽可能好的药皮焊条”. 5. hard spots must be avoid and gradual tapering off of stiffness is necessary if defects in service are to be minimized . If 引出从句中的 are to be minimized 为“ be+动词不定式的被动态”，在这里便是校订条 件，与 if 相呼应，构成条件状语从句。此句直译为：“如果要使用营运中的机械故障减到 最少，那么必须避免硬点，并且逐渐减小刚性
