7307.93.90 - With an inside diameter of 360 mm or more

This HTS category, 7307.93.90, specifically covers butt welding fittings for tubes and pipes made of iron or steel that have an inside diameter of 360 millimeters or greater. These fittings are designed for permanent joining of pipes and tubes through the process of welding, ensuring a continuous and leak-proof conduit. Examples within this classification include large-diameter elbows, tees, reducers, and end caps intended for industrial applications where substantial fluid or gas transfer occurs.

This classification is distinguished from its sibling category, which covers butt welding fittings with an inside diameter of less than 360 mm. The primary differentiating factor is the physical size of the fitting, with 360 mm serving as the benchmark diameter for inclusion in this specific sub-heading. Therefore, any butt welding fitting, regardless of its specific shape (elbow, tee, etc.) or material composition within the broader iron or steel category, will be classified here if its inside diameter meets or exceeds 360 mm.

Within this category, further distinctions are made based on the specific type of iron or steel alloy. The subcategories differentiate between fittings made of iron or non-alloy steel and those made from alloy steel, excluding stainless steel. This granular breakdown allows for precise tariff application based on the material properties and potential end-use of the fittings, reflecting variations in cost and performance characteristics associated with different steel alloys.