In heavy industry, traditional bolting methods rely on "brute force"—using massive wrenches to overcome thread friction. However, this often leads to uneven tension and thread damage. The hydraulic nut revolutionizes this process by applying the principle of "softness overcoming hardness."

The Mechanism of "Softness"
The "softness" refers to hydraulic oil. When high-pressure oil is pumped into the internal chamber of the hydraulic nut, it acts as a flexible yet powerful medium. Unlike a rigid wrench, the fluid distributes pressure perfectly across the internal piston. This pressure creates a pure axial pulling force, stretching the bolt like a stiff rubber band.

Achieving Precision
Because the oil pressure is directly proportional to the force exerted (F= P x A, where F is force, P is pressure, and A is the piston area), operators can achieve surgical precision. By simply monitoring a pressure gauge, they can reach a target preload with an accuracy of ±3%.

Locking the "Hardness"
Once the bolt is stretched to the desired length, a mechanical retaining collar is screwed down to lock the position. When the oil pressure is released, the bolt’s natural desire to shrink back creates the permanent clamping force.By replacing friction with fluid pressure, hydraulic nuts eliminate the "grinding" of metal parts, ensuring that the connection is tight, uniform, and incredibly safe.