The HD series is filled with hydraulic oil and nitrogen, so when the impact head is hit by an external force, the piston rod is pressed into the cylinder, and the piston will force the hydraulic oil to flow out of the orifices of different sizes and enter the oil storage chamber. As the travel decreases, the orifice will be gradually closed, thereby achieving linear deceleration of the moving object.
The moving speed of the moving object gradually decreases as the travel of the buffer decreases. After the hydraulic oil flows into the oil storage chamber, the nitrogen gas originally above the hydraulic oil is reduced in volume due to the press-in of the piston rod, and the pressure is continuously increased. When the load is evacuated, the piston will return the piston rod to its original position under the pressure of nitrogen.