There are several key differences between regular nuts and high-strength nuts (high-strength bolts):
Material: Ordinary nuts are usually made of carbon steel, while high-strength bolts are usually made of alloy steel, such as 45 steel, 20mmtib, etc. Some alloying elements, such as chromium, molybdenum, titanium, etc., are added to high-strength bolts to improve their strength and corrosion resistance.
Strength Rating: The strength rating of high-strength bolts is usually higher than that of regular nuts. The strength grade of high-strength bolts is generally9 or 12Grade 9, which indicates its ability for tensile strength and shear strength. The strength grade of ordinary bolts is generally 46 or 5Level 8.
Tensile capacity: High-strength bolts have higher tensile capacity and can withstand greater tensile loads. This makes high-strength bolts widely used in structures that need to withstand high tension, such as large bridges, high-rise buildings, etc.
Installation preload: High-strength bolts need to be controlled and adjusted by preload due to their high strength and rigidity. Preload is the pressure exerted during the bolting process to provide structural stability and resistance to vibrations and external loads. Ordinary nuts do not require such preload control.
Corrosion resistance: High-strength bolts are usually made of alloy steel materials or surface treated, which have good corrosion resistance. Ordinary nuts require additional corrosion protection to protect their surfaces from corrosion.
Reusability: Regular nuts are reusable, while high-strength bolts are designed to be non-reusable.
Force characteristics: In addition to the high strength of its own materials, high-strength bolts can also generate extrusion force between components by applying pretension force to increase the friction of the screw. The ordinary nut uses the rod and hole wall to bear the pressure and force.
To sum up, there are significant differences between ordinary nuts and high-strength bolts in terms of material, strength grade, tensile capacity, installation preload, corrosion resistance, reusability and stress characteristics. In practical applications, the appropriate nut type should be selected according to the specific engineering needs and structural design requirements.