Although the forming head is a three-dimensional product, it is also integrated on the basis of the graphic design by the corresponding technology. We don't know if you have seen the design drawings of the heads, the different types of heads, the design drawings are different in terms of the size of the straight edge segments, and some do not even straight flange.

Just like spherical head, it doesn’t need a straight flange, and the elliptical head, the conical head, the dish head, etc. all need straight flange, but the size of the setting is different. The larger the straight edge of the elliptical head, the better. The larger the straight flange of the elliptical head, the better, but it can't be too big or it is not easy to form. In this regard, the country has formulated relevant standards for reference.

The reason why setting straight section is mainly to make the other parts such as the head and the rolled plate more effectively welded, which can play a gentle and excessive effect on the welding stress. Spherical head doesn’t need straight flange is that the deformation stress generated by itself after welding is relatively small, and it is unnecessary to rely on the straight flange for the transition.