First of all, double-head bolt is a fixed link function used to connect mechanical equipment, which is characterized by threads at both ends and screws of different thickness in the middle, also known as straight rods or shrinking rods, which are actually double-headed screws.

Standard reference specification for double-head bolts. In addition, double-head bolts need to be marked in accordance with GB1237 regulations, such as thread diameter of 12mm, length of 100mm, mechanical properties of grade 4.8 and untreated equal-length double-head stud marked as stud GB901M12 × 100.
Double-head bolts are mainly used in construction, transportation, hardware, construction sites and other fields, and their grades are generally 12.9, 10.9 and 8.8. At the same time, there are some regulations on marking methods and different types of double-head bolts and so on.
So, what is the function and use of double-head bolts?
Double-head bolts mainly play the role of fastening and connection, and are widely used in mechanical equipment, electronic products, ships and vehicles, water conservancy projects and so on. Among them, the double-head bolt can better fix the product, especially when the main body is large-scale equipment and accessories need to be installed, such as mirror, mechanical sealing seat and reducer frame. By screwing one end into the main body and putting a nut on the other end, it not only makes the installation of accessories more convenient, but also makes it easier to replace.
In addition, double-head bolts can also be used for connecting thick plates and places where hexagonal bolts are inconvenient, such as concrete roof trusses, roof beam suspension monorail beam suspensions, etc.
Generally speaking, double-head bolts are widely used in many fields, and their standardization not only meets the needs of all kinds of applications, but also improves the reliability and safety of their use.