What are the reasons for the fracture of stainless steel screws?

Stainless steel screws usually refer to steel screws that have the ability to resist corrosion from air, water, acid, alkali salt or other media.

According to the different alloy components, the focus is on rust resistance and acid resistance.

Although some steels are rust-proof, they are not necessarily acid-resistant, and acid-resistant steels are usually rust-proof.

What is the reason for the fracture of stainless steel screws?

1. The quality of the screws
2. The strength of the screw
3. The pre-tightening torque of the screw
4. The fatigue strength of the screw The material of the screw is unqualified, the heat treatment is unqualified, the product manufacturing process is unqualified,

The unreasonable selection of stainless steel screws will directly affect the harsh environment of use.

When these premises are standardized, most cases of stainless steel screw fracture are caused by loosening.

Because the situation of loosening and breaking of stainless steel screws is roughly the same as that of fatigue fracture, we can always find the reason from the fatigue strength.

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In fact, the fatigue strength is too great for us to imagine, and the fatigue strength of stainless steel screws is not used at all during the use process.

The cause of screw damage is looseness: After the threaded fasteners are loosened, huge kinetic energy mv2 is generated, and this huge kinetic energy directly acts on the fasteners and equipment.

The fasteners are damaged. After the fasteners are damaged, the equipment cannot work under normal conditions, which further causes damage to the equipment.

For fasteners that are subjected to axial force, the threads are broken and the bolts are broken.

For fasteners that are subjected to radial force, the bolts are cut and the bolt holes are punched into an oval.

The choice of thread anti-loosening method with excellent anti-loosening effect is the fundamental solution to the problem.

The loosening of screw fasteners has nothing to do with the fatigue strength of stainless steel screws:

Threaded fasteners can be loosened only one hundred times in the transverse vibration loosening experiment, and one million times of repeated vibration in the fatigue strength experiment.

In other words, threaded fasteners become loose when they use one ten-thousandth of their fatigue strength.

We only used one ten-thousandth of its capacity, so the loosening of threaded fasteners is not due to bolt fatigue strength.