7307.91.50 - Other

This HTS category, 7307.91.50, encompasses "Other" types of flanges made of iron or steel that have undergone machining, tooling, or other processing after their initial forging. These fittings are specifically designed for connecting pipes, valves, pumps, and other equipment to form a piping system, allowing for disassembly and maintenance. The processing applied post-forging distinguishes these flanges from those that remain in their as-forged state.

It is important to differentiate this category from its sibling, "Not machined, not tooled and not otherwise processed after forging." While both relate to forged iron and steel flanges, the critical distinction lies in the subsequent manufacturing operations. This category specifically includes flanges that have been shaped, smoothed, or otherwise altered after the forging process to meet precise dimensional tolerances or functional requirements, such as threaded connections or specially prepared sealing surfaces.

The subcategories within this classification are determined by the inside diameter of the flange. "With an inside diameter of less than 360 mm" covers smaller flanges used in various industrial applications, while "With an inside diameter of 360 mm or more" pertains to larger, often heavy-duty flanges utilized in substantial piping systems. This distinction is crucial for import and export declarations, as it helps customs authorities accurately identify the specific type and scale of the flange.