Necking-in
Spinning seamless integral cylinders represent a novel process and product in the industry. These cylinders come in four main types: steel seamless gas cylinders, aluminum alloy gas cylinders, composite cylinders with steel inner walls, and composite cylinders with aluminum inner walls. They are primarily used in breathing gas cylinders, CNG natural gas cylinders, and for transporting medium to large volumes of high-pressure gases.
The manufacturing process for seamless integral gas cylinders varies according to the material used. For aluminum alloy gas cylinders, typically made from 6061 aluminum plate or bar, the process involves plate stamping followed by heating the aluminum ingot. This is followed by back-extrusion into a cup shape, strong rotation to create the straight wall sections, and then hot closing to form the bottle shoulder and neck. In contrast, steel cylinders, usually made from 30CrMo, undergo hot spinning of tubular sections back covering, strong rotation for straight wall sections (or non-rotation), hot closing (900°C to 1000°C), and universal spinning to shape the bottle shoulder and neck.
