4682670 Dump Truck REDUCING VALVE for EH3500AC

Part number 4682670 is the original pressure reducing valve provided by Hitachi for the EH3500AC series large mining dump truck. This component is mainly used in hydraulic braking systems or lifting hydraulic circuits to stabilize and reduce the high pressure of the main system (usually 20-35MPa) to the required pressure of the branch (such as 8-12 MPa), in order to protect low-pressure components such as brake cylinders and lifting cylinders. Its universal models cover 181 ton rigid dump trucks such as EH3500AC-2 and EH3500AC-3, as well as large excavators such as Hitachi EX2600-7 and EX3600-7 that use the same series of hydraulic systems. As a key component of the original factory pressure control, its interface size and pressure regulation range are fully matched with the hydraulic system of the entire vehicle. The use of non-standard auxiliary components is strictly prohibited to avoid pressure loss, component damage, or brake failure.

This product is a pilot piston or direct acting pressure reducing valve, typically made of cast steel valve body, alloy steel valve core, and stainless steel spring. The maximum inlet pressure can reach 35MPa, and the outlet pressure adjustment range is usually 5-20MPa, with a pressure regulation accuracy of ± 0.5MPa. Its interface size is commonly G1/2 "or SAE 12, with a built-in filter (mesh ≥ 100) to prevent impurities from getting stuck. The working temperature range is -40 ℃ to+120 ℃, suitable for extreme mining environments. Structurally integrated pressure gauge interface and overflow protection function ensure automatic unloading when pressure exceeds the limit.

Inspection cycle: Check every 500 working hours or once a month. Key inspection: 1 Whether the export pressure is stable (fluctuation ≤± 0.3MPa); 2. Check for oil leakage in the valve body and interface; 3. Adjust whether the handle is flexible. Replacement timing: Replace immediately when the pressure cannot be adjusted, internal leakage exceeds the standard, or the valve core is stuck. Disassembly and installation: 1 Fully release the hydraulic system pressure; 2. Clean the area around the interface; 3. Use two wrenches to disassemble in opposite directions (to avoid twisting the pipeline); 4. Rinse the oil port before installing the new valve; 5. Tighten according to torque requirements (usually 40-60N · m).