What Are The Applications Of Stainless Steel Square Nuts?

Stainless steel square nuts have a wide range of applications in various industries and fields. Here are a few common application scenarios:

1. Mechanical equipment: stainless steel square nuts are commonly used in the assembly and fixing of various mechanical equipment. They can provide reliable connection and fastening effect to ensure the stability and safety of mechanical equipment.

2. Construction: Stainless steel square nuts are also widely used in construction projects. They can be used for fixing steel structures, connecting pipes and fastening building materials. Stainless steel square nuts are corrosion-resistant and can be used for a long time in wet and corrosive environments.

3. Automotive industry: stainless steel square nuts play an important role in the automotive industry. They can be used to fix body parts, engine components and chassis, etc.. Stainless steel square nuts have high temperature and wear resistance, suitable for automotive working environment requirements.

4. Electronic equipment: stainless steel square nuts are also commonly used in the assembly and fixing of electronic equipment. They can be used to fix circuit boards, connectors and housings. Stainless steel square nuts have good electrical conductivity and corrosion resistance, applicable to the requirements of electronic equipment.

For information on stainless steel square nuts manufacturers, stainless steel square nuts prices, and stainless steel square nuts suppliers, there are many suppliers in the market offering various specifications of stainless steel square nuts. Prices and services may vary among different manufacturers and suppliers, so we suggest you consider factors such as product quality, price and after-sales service when choosing. And Stainless Steel Square Nut is one of the main products of Zhejiang Myway Co.,Ltd, with complete specifications and short delivery time. If you need Stainless Steel Square Nuts, please contact us at ashley@myway-metal.com, we will provide you with high quality products and services.

Stainless steel square nuts are widely used in various industries as an important fastener accessory. Choosing the right specification and material of square nuts can not only ensure the reliability and stability of the fasteners, but also improve the working efficiency and safety. We hope this article is helpful for you to understand the application scope and related information of Stainless Steel Square Nuts.

Decarburization and carburization

2. Hardness and Strength

In the inspection of threaded fasteners, we cannot simply look up the hardness value in the relevant manual and convert it into a strength value. There is an influence of hardenability factor. Because GB3098.1 and GB3098.3 stipulate that the arbitration hardness is measured at the 1/2 radius of the cross section of the part. The tensile test specimen is also cut from the 1/2 radius. Because it is not ruled out that the center part of the part has a low hardness and low strength part.

Generally speaking, the material has good hardenability and the hardness can be evenly distributed on the cross section of the screw. As long as the hardness is qualified, the strength and guaranteed stress can also meet the requirements. However, when the hardenability of the material is poor, although the hardness is qualified according to the specified parts inspection, the strength and guaranteed stress often do not meet the requirements. Especially when the surface hardness tends to the lower limit.

In order to control the strength and guaranteed stress within the qualified range, the lower limit of hardness is often increased. For example, the hardness control range of grade 8.8: for specifications below M16, it is 26~31HRC, and for specifications above M16, it is appropriate to be 28~34HRC; for grade 10.9, it is appropriate to control it at 36~39HRC. Grades above 10.9 are another matter.

Hardness and Strength

3. Re-Tempering Test

Bolts, screws and studs of grades 8.8 to 12.9 should be re-tempered for 30 minutes at a temperature 10°C lower than the lowest tempering temperature in actual production. On the same specimen, the difference in the average hardness of three points before and after the test shall not exceed 20HV.

The re-tempering test can check the incorrect operation of using too low a temperature to barely reach the specified hardness range due to insufficient quenching hardness, and ensure the comprehensive mechanical properties of the parts. In particular, threaded fasteners made of low-carbon martensitic steel use low-temperature tempering. Although other mechanical properties can meet the requirements, the residual elongation fluctuates greatly when measuring the guaranteed stress, which is much greater than 12.5um. Moreover, sudden fractures may occur under certain conditions of use. Sudden fractures have occurred in some automotive and construction bolts. The above phenomenon can be reduced when tempering at the lowest tempering temperature. However, special caution should be exercised when making 10.9 grade bolts with low-carbon martensitic steel.

Re-tempering test

4. Hydrogen Embrittlement Inspection

The sensitivity of hydrogen embrittlement increases with the strength of the fastener. For external threaded fasteners of grade 10.9 and above, surface hardened self-tapping screws, and combination screws with hardened steel washers, etc., dehydrogenation treatment should be carried out after electroplating.

Dehydrogenation treatment is generally carried out in an oven or tempering furnace at 190~230℃ for more than 4 hours to diffuse hydrogen.

Threaded fasteners can be tightened on a special fixture until the screw is subjected to a tensile force that satisfies a certain stress, and then maintained for 48 hours. After loosening, the threaded fasteners do not break. This method is used as a hydrogen embrittlement inspection method.

Hydrogen embrittlement inspection