Sany Original Allocation Valve Port Safety Valve HVME400-070000 02.02.09.00089, Sany Material Code: 150688000156

HVME400-070000 Overload Safety Valve (Port Overflow Valve)
Hengli Part Number: HVME400-070000｜02.02.09.00089
Sany Material Code: 150688000156
Compatible Valve Body: Hengli HVME400 Main Control Valve (Sany 150601080024A)
I. Compatible Machine Models
SY365H, SY375H, SY395H, SY485H (Dedicated to National IV HVME400 Distributor Valve; cannot replace Kawasaki KMX32 overload valve)
II. Parameters and Installation
1. Original Factory Set Pressure: 35.5 MPa (355 bar), single-action overload protection, higher than system main relief pressure of 32.5 MPa
2. Installation Location: Plug-in holes on the side of each action valve plate (independent overload for boom/arm/bucket/rotation), single-circuit action port safety overflow
3. Structure: Cartridge direct-acting overload safety valve, integrated assembly of pressure adjustment screw + conical valve + high-strength spring
III. Function (Single-Action Independent Protection)
1. Single-cylinder pressure buildup overload relief: When the boom is jammed or the bucket bites hard soil causing overpressure, this valve relieves pressure independently to protect the cylinder seals, cylinder barrel, and pipelines.
2. Differentiate from system main relief: The main relief controls the overall system pressure at 32.5 MPa, while this overload valve controls the peak pressure of a single actuator at 35.5 MPa. Hydraulic excavator actions with pressure buildup do not reduce system pressure.
3. Single-action weakness/relief corresponds only to the individual action, without affecting the full vehicle pressure.
IV. Common Faults
1. Valve spool scoring causing internal leakage: Single-action weakness, poor lifting, bucket lowering relief, with other actions normal.
2. Spring softening: Pressure fails to reach standard, leading to arm drop during heavy-load actions.
3. Sticking in normally open position: Corresponding action relieves pressure upon any load, with normal operation under no load.
V. Part Differentiation
- Original Factory Hengli: Valve body with engraved model number, factory preset to 35.5 MPa, stable for mining heavy-duty applications.
- Aftermarket: Prone to pressure drift, frequent cylinder pressure buildup leading to easy relief.