The most common application in the industry is to use DTFLock® locknuts in combination with standard bolts to form a locklock thread system. Let us first reexamine this relationship. In Figure 1.0, the tooth tip of the male thread of the standard bolt is pressed against the 30 ° wedge surface of the female thread. Because the contact surface is small, the contact stress is large. Under the action of torsional moment, the tooth tip of the bolt will plastically deform. At this time, the contact part is liable to cause "cold welding" and cause the phenomenon of "smooth teeth". At the same time, in the long-term working state of this bolt pair, the contact part continues to produce slight compression deformation, which also easily causes the axial force of the external thread to become small, so that it becomes loose. This point is obviously exposed when the impact force exceeds a critical point in the transverse vibration experiment. In a lot of practice, this problem also constantly plagues our customers. In fact, in order to overcome this weakness, a special arrangement was made for the assembly process of the DTFLock® locknut on the main engine of the spacecraft. That is, first tighten the DTFLock® nut, then loosen it, and then tighten it three times. In the process of three repeated tightening, the plastic deformation of the tooth tip of the bolt has been completed, and the entire bolt pair has formed a stable bite state when it is finally tightened. Both the resistance to "cold welding" and "sliding teeth" have been improved, and the loosening resistance has also been improved. DTFLock® Bolt Splices (DTFLock® 2.0) is a new generation of high-performance fastener splices developed on the basis of Spiral® thread technology. Problems, especially the effectiveness of wheel bolt connections for heavy trucks and large buses. On the actual application test project of Daheishan Molybdenum Mine, the dump trucks used in the original mining area withstood extremely severe working conditions, bumpy roads, overloaded vehicles, continuous operation 24 hours a day, frequent disassembly and replacement of tires, In this case, the ordinary wheel bolt pair has a very short service life. And the wheel bolt pair of Shi Bilai has been installed and tested for a long time on the heavy truck mining in Daheishan Molybdenum Mine, showing excellent performance, and the average life span is more than doubled than that of ordinary bolt connection. Based on the above-mentioned basic design ideas, DTFLock® bolts were consciously increased in the middle diameter during design to make the tooth tips thicker. The anti-pulling ability of the bolt is further improved. In addition to inheriting the inherent advantages of DTFLock® locknuts, DTFLock® bolt pair has many advantages such as over-tightening resistance, suitable for frequently disassembled parts. Summarizing its advantages can be summarized as "four defenses" and "four resistances."