A193

A193 is a designation used in several domains to identify different, unrelated things. The most widely recognized reference is in engineering standards as ASTM A193, which designates specifications for alloy-steel and stainless-steel bolts, studs, and other externally threaded fasteners intended for high-temperature or high-pressure service. The standard is published by ASTM International as A193/A193M and covers material grades, chemical composition, heat treatment, mechanical properties, and testing requirements. It is commonly employed in the chemical, petroleum, and power-generation industries and often works in conjunction with related standards such as A194 for nuts.

In transportation, A193 is used as a road designation in the United Kingdom and in other countries that number roads with an "A" prefix. In these systems, A193 typically refers to a specific route or segment within a regional network, and the exact route is determined by the national or regional authority.

In other contexts, A193 may appear as an internal catalog or part number used by manufacturers, suppliers, or institutions to identify a particular component, product variant, or document series. Because the code is short and generic, its meaning is highly context-dependent.

See also: A192, A194, and related A-number designations in standards, roads, and product catalogs.