Průmyslové novinky

Měly by být šrouby utaženy co nejtěsněji?

2021-06-22
Šroubovanýšroub is subjected to two forces, one is downward and the other is upward. Thešroub rotates down along the thread, and a downward axial force is generated in the process of contact with the thread.
At the same time, there is an upward force corresponding to the downward axial force. This force comes from the upward distributed force generated by the contact between the nut and the lower plane. A tightenedšroub should ensure that the upper and lower forces are balanced with each other. Due to the function of šrouby, the material ofšroubs has two requirements, one is rigidity and the other is toughness, both of which are indispensable.

Ale všechny tvárné materiály mají jednu společnou věc, tj. Existuje mez tolerance napětí. V mechanice je tato mez reprezentována křivkou napětí-deformace. Nemusíme být příliš esoteričtí. Potřebujeme jen vědět, že v procesu šroubováníšroub, thešroub is a kind of elastic part, and its elasticity will take effect.

Jakošroubse postupně utahuje, pružný účinekšroub will approach a limit. Once this limit is broken, thešroub will enter the yielding stage from the elastic stage.
Once thešroub enters the yield stage, it will produce permanent deformation. This deformation is irreversible, which means that thešroub will fail. In real life, the phenomenon of tripping when we continue to tighten thešroub is caused by this reason, and once it is tripped, it is impossible to screw it again, because thešroub has been permanently deformed, and it can be seen that thešroub is not screwed properly the tighter the better.