A blanking head, also known as an end cover, is a component used to seal the ends of containers, isolating the internal and external media. The blanking heads for cylindrical containers are typically rotational shells. They can be categorized by the shape of their surface into convex, conical, flat, and composite shapes. A convex blanking head refers to a head with an outwardly convex surface, such as hemispherical, elliptical, dish-shaped, and seamless spherical heads. Some gas cylinders use a composite bottom blanking head with an inward-facing convex surface, which ensures strength while meeting safety requirements.