The most common thing in hardware products is the screws

Update:20-09-2019
Summary:

The most common thing in hardware products is the screw […]

The most common thing in hardware products is the screws. These small screws can be seen everywhere, whether at work or in study. These small screws are just constructed on the table we are learning to use, and a table. How many screws are needed for the production, the number of screws used in each table is different, and the simple table structure can be basically four to ten. We will not say too much theory here. The structure of the screw is such that the precision screw is so heat treated?
Visible in the application of the screw. Similarly, the participation of screws in the level switch is also indispensable.

Vibrating level switches (such as tuning fork liquid level switches) work continuously for a long time in high-frequency vibrations. This requires that the vibrating parts must have a certain strength and toughness to resist local damage and stress fracture, so the parts are fine. The rationality of the structural design is particularly prominent. Among them, the structural design of the screw is a typical one.

There is a smooth connecting section between the screw head and the threaded part. This structure reduces the frictional resistance during vibration and increases the joint strength of the bolt. The structure of Fig. 2 is that the threaded portion is directly processed to the head of the screw, and there is a breaking stress at the joint of the thread and the shoulder of the screw head. In the process of high-frequency vibration, the portion is easily broken and fails, resulting in equipment failure. The red circle shown in Figure 3 is the crack that occurs when the screw is pressed. This is where the screw structure is the weakest.

In the heat treatment of precision metal screws, Yiding Hardware is called screw hardening, including stainless steel screws and iron. The former is harder because it is hard enough, so the latter is relatively hard. .
When it comes to heat treatment, it can be divided into two processes of heating and cooling. The ideal heat treatment quality can be obtained by properly controlling the two. The essence of controlling the cooling process is the scientific use of quenching medium.