Nuts

About nuts

Nuts are internally threaded fasteners designed to mate with a corresponding externally threaded fastener, typically a bolt or screw, to create a secure joint. Their primary function is to resist axial loads and prevent loosening. Common types include hex nuts, which are general-purpose and available in various grades (e.g., ASTM A563, ISO 4032), and nylon-insert (nyloc) nuts, which incorporate a polymer insert to provide prevailing torque and enhanced vibration resistance. Flange nuts integrate a washer-like base to distribute load over a larger area, reducing the need for a separate washer and improving joint integrity. Wing nuts feature ‘wings’ for manual tightening without tools, ideal for applications requiring frequent assembly and disassembly. Coupling nuts are elongated for joining two externally threaded components, while jam nuts are thinner and often used as a locking mechanism against another nut. Selection criteria include nominal diameter, thread pitch (e.g., UNC, UNF, metric fine/coarse), thread class (e.g., 2B, 6H), and material properties such as tensile strength, proof load, and corrosion resistance. Common materials include carbon steel (plain, zinc-plated, hot-dip galvanized), stainless steel (304, 316), brass, and nylon.