High-strength bolts are divided into three categories:
  Friction type high-strength bolts: suitable for the connection of beams and columns of steel frame structures, the connection of solid web beams, the connection of heavy crane beams in industrial plants, the connection of braking systems and important structures bearing dynamic loads.
  Pressure-bearing high-strength bolts: It can be used for shear connections in static-loaded structures that allow a small amount of sliding or in members that indirectly bear dynamic loads.
Tensile high-strength bolts: When the bolt is under tension, its fatigue strength is low, and its bearing capacity is not easy to exceed 0.6P under dynamic load (P is the allowable axial force of the bolt), so it is only suitable for use under static load. Such as flange butt joints and T-joints of compression members.
  High-strength bolts are made of high-strength steel, or bolts that require a large pre-tightening force can be called high-strength bolts. High-strength bolts are mostly used for the connection of bridges, rails, high-pressure and ultra-high-pressure equipment. The fracture of such bolts is mostly brittle fracture. The high-strength bolts used in ultra-high pressure equipment require a large prestress in order to ensure the sealing of the container.