A conical head is a closure with a conical surface on the shell. Its features include uniformly changing the velocity of the medium as it passes through, facilitating the removal of thick liquids and materials containing solid particles. However, it has poor mechanical properties, and the discontinuous stresses at the junction with cylindrical shells or pipe connections due to shape changes are significant. To reduce these discontinuous stresses, an arc transition with flanged structures or locally thickened structures can be adopted at either the large or small end of the conical shell. According to Chinese pressure vessel design specifications: when the semi-锥 angle is greater than 30°, the large end of the conical shell should use a flanged structure; when the semi-锥 angle is greater than 45°, the small end should use a flanged structure. Due to the larger wall thickness of conical heads, manufacturing is inconvenient, and they are only used when required by the process.