GB/T 77-2007

GB/T 77-2007 specifies the dimensions, technical requirements, and marking of hexagon socket set screws with flat point, which are used to secure relative positions between two mechanical components by applying axial clamping force through a flat contact surface. These screws are commonly applied in machinery assembly, automotive parts, and precision instruments where a flush or non-protruding fastening solution is required to prevent loosening under vibration or dynamic loads. The standard ensures interchangeability and reliability in industrial fastening systems, particularly in applications requiring frequent adjustment or disassembly.