ANSI B18.2.1 Flange Bolt

Leader-Fastener® ANSI B18.2.1 Flange Bolt are hex washer head bolts with a flat washer bearing surface. They are made from high-alloy steel, and commonly used on truck frames, hence the name frame bolt. The flange eliminates the need for washers. They are covered under ASME Standard B18.2.1

Hex Flange Screws are a form of hex head bolt with a wider flange under the head. The circular flange under the head serves as a washer spreading the load and providing nearly four times the bearing area of a regular hex screw. Flange bolts are commonly used in the frames of vehicles, especially trucks. Non-serrated flange bolts are most commonly used.

The ASME B18.2.1 hex flange screw is constructed in three sections including a Hex Flange Bolts are regular hex head bolts with built-in washer and externally threaded body. Flange bolts comes with plain or serrated flange configuration. Hexagon flange bolts, flange bolts, frame bolts are other alias of hex flange bolts. Hex flange bolt dimensions are defined in both metric and imperials sizes with unified national coarse pitch (UNC), fine pitch (UNF), fixed pitch (UN) and iso metric thread profile. These are produced across all material categories and astm specifications. Hexagon flange bolts are commonly used in automotive industry, specially in truck and heavy vehicular frames.

hexagonal head, a disc-like flange, and a threaded rod. It has same tightening function as that of a common hex cap screw plus a washer. Due to the extensive contact surface between the flange and the work piece, the better tightening can be assured. The bottom surface of the flange may be flat and smooth, or corrugated.

Leader-Fastener® ASME B18.2.1 Hex Flange Screws, Inch Series