The quality of a 304 or 316 stainless steel nut is directly related to the operational stability of the entire equipment. Stainless steel nuts are indispensable components in equipment assembly and can be regarded as the core parts for the fastening connection of products. The production of stainless steel nuts involves multiple links such as materials, molds, and production technology. Every time we see batches of 304 and 316 stainless steel nuts coming off the workshop production line, being packaged and shipped out, a sense of pride wells up in our hearts, making us completely oblivious to the monotony of this industry.
When stainless steel nuts are stored in the atmosphere for a long time, if they are exposed to specific environments beyond the corrosion resistance limit of the material itself, rusting will occur. Severe corrosion of stainless steel nuts will directly damage the internal threads, making disassembly extremely difficult in later stages. Careless operation may even cause the stainless steel nuts to seize together with the bolts, bringing great inconvenience to equipment maintenance and parts replacement.
The time cost of removing a seized stainless steel nut due to corrosion is extremely high. Sometimes, a delayed delivery of a large order worth tens of millions of yuan may be caused by the untimely replacement of a single small stainless steel nut. Through long-term practical analysis, the corrosion of stainless steel nuts can be divided into three main types: the first is pitting corrosion. This type of corrosion is basically caused by material defects, such as insufficient material purity or internal impurities. The second is crevice corrosion. This type of corrosion usually develops gradually during later installation and use, with various inducing factors, including excessively harsh operating environments or the dripping and adhesion of strong acidic substances on the nut surface. The last one is general corrosion. This is the most harmful type of corrosion. Once such corrosion occurs, the nuts must be replaced in a timely manner, and the corroded samples should be sent for in-depth testing to verify whether the material meets the standards. This kind of situation is basically caused by the use of counterfeit stainless steel materials, which is a serious quality issue, and it is necessary to consider replacing the original supplier.
Stainless steel nuts will also experience accelerated corrosion in high-temperature environments. Long-term exposure to high temperatures will seriously affect the mechanical properties and corrosion resistance of stainless steel nuts, and such situations should be avoided as much as possible. For carbon steel nuts, corrosion under high temperatures can be directly observed from the appearance, while the initial signs of corrosion on stainless steel nuts under high temperatures are relatively hidden and difficult to detect in a timely manner with the naked eye.
Therefore, we must select qualified stainless steel nut products and try our best to avoid corrosion caused by nut quality issues during structural installation and design application. Many enterprises neglect the management of stainless steel nut storage in order to cut costs, and do not pay attention to the corrosion spots found on the surface during use. To facilitate timely delivery, they adopt secondary cleaning and polishing to make the surface of stainless steel nuts look as good as new, but the internal corrosion has already damaged the performance of the nuts, leaving huge potential safety hazards. When unqualified stainless steel nuts flow into the production line, it is difficult for operators to judge the quality of the nuts with the naked eye, and they will only install them directly as qualified products. Such nuts are also particularly prone to seizure during installation. We have emphasized the seizure issue of stainless steel fasteners many times. The reason why we keep mentioning this problem is that seizure of stainless steel bolts cannot be completely eliminated by any means. If such problematic nuts are used, the probability of seizure will increase significantly. Even if more attention is paid during later installation, such as adding spring washers or adjusting torque wrench parameters, it will not help. Because after corrosion occurs, the threads will undergo invisible deformation, and the corrosion spots will leave stains in the thread gaps, both of which will greatly increase the probability of seizure between nuts and bolts.
