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There are two methods for forming flangeless conical heads: one is rolling them using a sheet rolling machine, and the other is pressing them using a hydraulic press (or hydrostatic press). Whether to use rolling or pressing for shaping is determined based on the specifications of the conical head (such as the diameters of the large and small ends, thickness, half apex angle, etc.), equipment capabilities, manufacturing experience, and operational practices*. Rolling offers advantages in terms of dimensional accuracy, surface quality, and production efficiency compared to pressing; however, in actual manufacturing, since the operating parameters of rolling machines cannot meet the dimensional requirements, thickness, or angles of certain conical end caps, pressing is the only viable method for shaping them. 1. Rolling formation: The process equipment for rolling formation is the same as that used for rolling single-layer welded circular sections. However, since the radius of curvature of the conical head changes gradually from the smaller end to the larger end, it is more difficult to roll it. The two common methods are as follows: One is to adjust the upper roller to an appropriate inclination angle when using a rolling machine to form the conical head, so that the line of contact between the upper roller and the fan-shaped blank remains along a ray of the fan-shaped blank (as shown in Figure 15.8.1), thereby ensuring that the smaller and larger ends of the fan-shaped blank are fed in synchrony. The other method involves using resistance fixtures on the rolling machine to form the conical head; these fixtures also help to control the appropriate feeding speed of the inner and outer arc surfaces of the fan-shaped blank. Resistance fixtures are divided into frame-type and separate-type, suitable for rolling small and large tapered end caps respectively. 2. Press forming: During press forming, whether it is whole-plate forming, forming after panel assembly, or forming individual segments first and then assembling them into a conical head, fan-shaped material cutting is used, and the process equipment and methods employed are the same as those for single-layer press-welded circular sections.