Why is there a safety hazard in connecting the hub and blade with bolts?

The biggest safety hazards come from the difference in material hardness between bolted steel and aluminum alloy, manufacturing process errors and technical requirements for on-site installation.

First of all, the converted hardness of bolt steel is about 35 degrees, and the hardness of aluminum alloy is about 16 degrees, once the two materials rub against each other, shift or even collide, aluminum alloy will inevitably be cut, accumulated cutting damage may cause blade damage, fracture.

Secondly, for the hub petiole inserted into the installation method of the inner cavity of the aluminum alloy blade, the aluminum alloy inner cavity processing is difficult, there are differences and errors in the manufacturing size, it is difficult to form a tight fitting joint surface on the surface of the petiole and the inner cavity of the blade, when the fastening bolt presses the petiole and the blade, the joint surface is difficult to form sufficient contact friction, at this time, in the event of violent mutual movement, the blade and the petiole may be displacement of each other, resulting in the thread cutting of the fastening bolt aluminum alloy blade.

Finally, the connection work between the petiole and the blade needs to be completed at the installation site. Due to the construction period, responsibility, skill

The difference between energy and installation equipment, it is difficult to ensure that the height of the compression force of the fastening bolt is consistent, too large the compression force can easily lead to the collapse of the blade surface, and too small pressing force may lead to the cutting of the blade by the thread.