The largest excavator accessories distribution center of China.
One-way overload valve
Over-opening valve opening dynamics
Check valve open
Principle of one-way overload valve
1.Overflow function
When the oil pressure rises to the preset pressure of the spring B, the spool (A) opens: the oil bypasses the spool A through the (C) side hole: it flows to the (E) channel.
The oil flow creates a pressure drop before and after the hole (J): the piston (H) is moved to the right and sits on the top of the spool (A).
The hydraulic oil flows from (1) chamber through (A) the top throat of the spool into the (2) chamber: then bypasses (A) the spool through the (C) side hole and flows into the (E) channel.
As the pressure at the throat K decreases, the pressure in the chamber (1) x d1 cross-sectional area> (2) the pressure in the chamber x d2 cross-sectional area, the valve core (C) is pushed away and the oil flows into the low-pressure channel.
2.compensation function
Prevent cavitation in the hydraulic oil circuit during work or when unexpected forces act on the machine.
The pressure of the oil cylinder is usually higher than the pressure of the oil tank, and d3 <d4. Therefore, the poppet valve F will not
move.
When the cylinder port pressure drops below the tank pressure, the valve core F is opened due to the area of d3 and d4, and the hydraulic oil flows from the tank oil passage to the cylinder port to avoid the occurrence of cavitation
