90-degree elbow production method of sampling?

Stroke instead of iron plate, the specific operation is as follows:

1, first of all, use a straightedge to draw a 90-degree perpendicular to each other in the upper-right corner of the right coordinate system of the region, as shown in the figure below.

2, assuming that the diameter of the pipe we use is 400, then it can be determined that the medium diameter of the pipe used is 200, drawn in the figure.

3, assuming that we use the number of half-section is 4, then you can divide the equipoints in the diameter of the center, the number of equipoints N = (elbow cutoff A-1) * 2, here A = 4, so N = 6, 6 equipoints drawn in the figure.

4, then make a radius of 54.5 semicircle, and 6 equal parts of this semicircle, over the 6 equal parts of the vertical line.

5, then according to the circumference of the pipe part of the expansion, and do equal points, because the figure is symmetrical, draw half can be.

6, in step 5 of the equidistant line intercepted half section of the projection map on the corresponding projection line distance, connect these interceptions into a smooth curve, and then symmetrical fold can be.