DIN931 Hexagon Head Thick Shank Half-thread Bolts Overview

DIN931 hexagon head thick shank half-thread bolts are mechanical connecting parts that conform to the German Industrial Standard (DIN) 931 specification. Their heads are hexagonal, which is convenient for tightening or loosening operations using tools like wrenches. The so-called “thick shank” means that the diameter of the smooth shank part of the bolt is relatively large, capable of providing a strong bearing capacity. “Half-thread” indicates that only a part of the bolt shank is threaded, and the other half is a smooth shank. Such a design can ensure the tightness of the connection and, at the same time, enable the bolt to have better guidance during the installation process, and also allow for a reasonable distribution of stress when subjected to tensile and shearing forces.

Application of Hexagon Head Half-thread Bolts

• Construction Industry: They are widely used in the connections of steel structure buildings. For example, when connecting steel beams and columns, DIN931 hexagon head thick shank half-thread bolts can provide reliable fastening force to withstand the tensile and shearing forces generated by the building’s own weight and external environmental factors (such as wind loads, earthquake forces, etc.). Due to their thick shank design, they can better ensure the stability of the connection when connecting thicker metal components.
• Mechanical Manufacturing Field: They are used for the assembly of various mechanical equipment. Such as the connection between the bed and the worktable of a machine tool, or the fixing of the outer casing of large machinery. The half-thread structure enables the bolt to be positioned more accurately during the tightening process, and the thick shank part can increase the contact area with the connecting parts, effectively dispersing stress and preventing the connecting parts from deforming or being damaged.
• Automobile Industry: They are used in some connecting parts of automobile chassis and frames. During the driving process of automobiles, various complex forces are generated, such as the impact force caused by bumps, the inertial forces during braking and acceleration, etc. These bolts can firmly connect the components of the chassis and the frame, ensuring the safety and stability of the automobile structure.

Features of Hexagon Head Half-thread Bolts

• High Strength Bearing Capacity: The thick shank design enables them to withstand large tensile and shearing forces. For example, in the connections of some heavy machinery, their tensile strength can reach a very high level. The specific value varies according to the grade and size of the bolt, and generally can meet the requirements of high-strength connections, effectively preventing the connecting parts from loosening or breaking when subjected to large external forces.
• Good Stress Distribution: The half-thread structure allows the bolt to distribute the tensile and shearing forces reasonably between the smooth shank and the threaded part during the tightening process. When subjected to external forces, the smooth shank part can play a supporting and load-sharing role, reducing the stress concentration in the threaded part, thereby prolonging the service life of the bolt.
• Easy to Locate and Install: The half-thread design enables the bolt to use the smooth shank part as a guide during installation, facilitating accurate insertion into the installation holes, especially in some occasions where high installation accuracy is required, such as the assembly of precision machinery. This design can improve the installation efficiency.
• Convenient for Tightening and Removing: The hexagonal head shape meets the requirements of using standard tools. Ordinary hexagonal wrenches can be used to conveniently tighten and remove the bolts, and during the tightening process, good torque transmission can be provided to ensure that the bolts reach the appropriate fastening force.