Do you spend too much time bending sheathing sheets and still need to allow for edge allowance to avoid gaps during assembly? When assembling the sheathing sheets, are the welds too large to fill the gaps between the sheathing and the sheathing? Do you have to break the sheathing sheets into smaller ones, with a large number of additional welds? Excessive deformation of sections during assembly, increased time for assembly and welding work? Does the new vessel's hull look ribbed like a dead horse?
What is the problem? Outdated equipment and unskilled labor? Why does the assembly of some hulls proceed quickly, efficiently, on time and the shipyard earns a profit, while on others it loses both money and reputation?
Just take a closer look at the model of the surface of the ship's hull, which was used to prepare the working documentation. I am sure that the answer to all these questions will be found here. But this must be done before the metal cutting stage begins. The ideal solution would be to check the smoothed surface before production documentation begins.
Just the facts. Increasing the gaps beyond the tolerance by 2-3mm contributes to:
-increase in scrap welds by 10-15%,
-increasing the deformation of the structure from welding by 1.5-2 times,
-increasing the consumption of welding materials by 10-15%,
-increasing the time spent on manufacturing welded structures by 2-3 times.
And these are just the problems that arise during the assembly stage of the structure.
You can add to this list:
- time spent on bending sheets that cannot be bent,
- costs of correcting errors when modeling structures based on poor-quality surface shape,
- internal stresses in the structure, which will come back to haunt the vessel’s operation stage,
- increased corrosion of the hull.
Why the inner constructions of the hull doesn’t fit with the seemingly beautiful hull shape? After analyzing a large number of surfaces that are sent to us, I came to the conclusion that most of them have not been tested for smoothness quality and manufacturability. The shipyard hopes that it will receive from the designer high-quality working documentation made on a high-quality surface of the ship's hull, and the designer, as a rule, does not take into account the technological features of production. All surface testing often comes down to showing the rendering. Another big problem is the lack of reliable controls in the software used. Bent frames structures, shell plates or profiles, will bend along natural curves close to the shape of a spline. Flat sheet parts of inner structure are cut out on a machine and the curve along which the part is adjacent to the shell is taken from a mathematical model of the ship's surface. Problems arise if the surface model is made poorly - unnecessary bends, flattening, etc. This may not be visible on the drawing, but at the real scale of the ship's hull, gaps of up to 10 mm or more can occur.
All these problems can be avoided. If you doubt the quality of smoothing your surface, send me a model for expert evaluation, and I will do it absolutely free.
Shipbuilding, as a business, is associated with a large number of different financial and economic risks. Unnecessary risks and costs for assembling and welding the ship's hull can be easily avoided by using a high-quality model of the ship's surface.