Processing technology for high-strength large hexagon head bolt used for steel structure

Abstract

The invention discloses a processing technology for a high-strength large hexagon head bolt used for a steel structure and belongs to a processing technology for a high-strength connecting piece. The high-strength large hexagon head bolt is processed by less or non cutting including one time of hot forging forming and three times of cold extrusion forming, wherein the hot forging forming is bolt rail forming. The first time of cold extrusion forming is screw forming, the second time of cold extrusion forming is upper screw thread section forming, and the third time of cold extrusion forming is thread forming. The invention mainly adopts the cold extrusion process for bolt production, improves the strength of the bolt, optimizes the production process of the bolt, overcomes the delay fracture and fatigue fracture of the high-strength bolt, ensures that the bolt is not easy to fracture in the use process and reliably connected, prolongs the service life of the bolt and can more meet the use requirement for the high-strength large hexagon head bolt used for the steel net frame bolt ball node in modern society.

Description

technical field [0001] The invention relates to a processing technology of a high-strength connecting piece, in particular to a processing technology of a high-strength large hexagon head bolt for a steel structure. Background technique [0002] High-strength large hexagon head bolts for steel structures are commonly used fasteners in the machinery industry. The current processing method is generally formed by turning, and its strength is often difficult to guarantee. When the tensile strength exceeds a certain value, in the places where the gaps are concentrated For example, the transition between the rod and the head or the root of the thread is likely to cause delayed fracture and fatigue fracture, which will seriously affect the quality of the project. In severe cases, it will cause safety accidents due to insufficient connection strength. Therefore, traditional high-strength bolts need to be replaced. Research and improve the advanced production process, in order to eff...

AI Technical Summary

Problems solved by technology

[0002] High-strength large hexagon head bolts for steel structures are commonly used fasteners in the machinery industry. The current processing method is generally formed by turning, and its strength is often difficult to guarantee. When the tensile strength exceeds a certain value, in the places where the gaps are concentrated For example, the transition between the rod and the head or the root of the thread is likely to cause delayed fracture and fatigue f...