Working principle of hydraulic breaking hammer

Hydraulic breaking hammer has become an important working tool of hydraulic excavator. Some people also install the hydraulic breaking hammer on the excavator loader (also known as two heads busy) or wheel loader for breaking operation.

It has a wide variety of names, including hydraulic crusher, hydraulic pick, hydraulic gun, crushing head, etc. The term of our national standard is hydraulic impact crusher.

Today we will introduce its working principle.

1、 Start up phase

The hydraulic oil flows through the check valve to the accumulator, the pressure control valve, the main valve element and the bottom of the piston. The spring force keeps the pressure control valve closed, preventing oil from returning to the tank from the upper part of the piston and preventing the piston from moving. The pressure in the circuit increases, compressing the nitrogen in the battery. Note: the top of the piston is always vented to the atmosphere.

2、 Backhaul acceleration phase

At the beginning of the return stroke of the piston, the last impact of the piston has ended, and it is in a state of instantaneous pause. At this time, chamber V2 of the main valve is a low-pressure chamber, while chamber V4 is a constant high-pressure chamber, so the main valve core is at the lower limit position. In this way, the piston front chamber V1 is connected with the high-pressure oil through the main valve core, while the piston rear chamber V3 is always connected with the oil return chamber, which is a low pressure. Therefore, under the action of the high-pressure oil in the front chamber, the piston makes a return acceleration movement and compresses the nitrogen in the tail nitrogen chamber for adiabatic compression.

3、 Return phase

When the piston finishes striking, the control end of the main valve element returns to the oil tank and moves to the left to start the next lifting ring. Note: the oil under the upper piston flange acts as the piston hydraulic brake.