What is the distinction of fine thread screw and coarse thread screw?

How to determine fine thread screw and coarse thread screw, what is the difference between them?

The so-called coarse thread screw, can be defined as the standard thread, and fine thread screw is relatively coarse thread, in the same nominal diameter, the number of thread per inch is different, that is, the pitch is different, coarse thread pitch, and fine thread pitch is small. Coarse thread screw is characterized by good strength and interchangeability, thread Angle is also large, convenient disassembly and assembly and standards can be compared, coarse thread screw labeling does not need to mark the pitch.

Fine thread screw in order to supplement the coarse thread screw can not meet the requirements of other use, fine thread screw also has a pitch series, but its pitch is small. It is characterized by self - locking, anti - loose, and the number of thread, play the role of sealing. As applied in some precision scenes, fine-thread screws can be easily controlled and adjusted. The disadvantage is that the tensile value and strength should be low, the thread is easy to damage, it is not recommended to remove many times. And fine-thread screws should be marked when the pitch, to show the difference between the coarse thread and screws.

In fact, like fine-thread screws and coarse thread screws mainly depends on what you apply to the scene.

Coarse thread thread and fine thread thread screw are used for fastening. Fine thread screw is generally used to lock thin-walled parts and parts with higher requirements for vibration prevention. Fine thread thread has good self-locking performance, so it has strong anti-vibration and anti-looseness ability, but because the thread depth is shallow, the ability to bear greater tension is worse than that of coarse thread thread.

When the anti-loose measures are not taken, the anti-loose effect of fine thread thread is better than that of coarse thread. It is generally used for thin-walled parts and parts with high requirements for anti-vibration. When adjusting, fine thread has more advantages.

The disadvantages of fine thread thread: it is not suitable for the application of materials with excessive coarse tissue and poor strength. When the tightening force is too large, it is easy to slip.