When we intend to control the accuracy of the pipe-fitting in ship, the following factors and the relation betwwn them must be considered. Those are the accuracy of pipe proper, of the pipe-fitting, and of the hull construction. It is rather easy to control each factor independently, but the total tolerance are to be detetermined in relation with those factors each other. Here, in this study, we tried to resolve this problem by means of the summation of the errors of pipes, and the calculation of the elastic deformation of pipe units. By this method, we can give the reasonable tolerance to each control factor, and on the other hand we can get some date for piping design.
