723-10-18900 8457710 Excavator PC40MR-2 PC45MR-2 PC50MR-2 PC55MR-2 Hydraulic Main Pressure Relief Valve Action Control Valve

723-10-18900 8457710 Excavator PC40MR-2 PC45MR-2 PC50MR-2 PC55MR-2 Hydraulic Main Pressure Relief Valve Action Control Valve

Product Description

The GVO excavator relief valve, compatible with Hitachi excavators, is a key pressure control valve in the hydraulic system. It regulates hydraulic pressure, releases overload pressure, protects core hydraulic components such as the main valve and hydraulic pump, and ensures stable operation of the entire machine.

This relief valve is precision-machined from high-quality steel and undergoes overall quenching treatment. Equipped with oil-resistant and high-pressure-resistant seals, it boasts excellent sealing performance, impact resistance, and wear resistance. Suitable for the high-pressure hydraulic conditions of excavators, it effectively prevents internal leakage, pressure loss, operational instability, and vibration.

Product Introduction

This GVO-branded cartridge-style relief valve is custom-engineered for the Komatsu PC40MR-2, PC45MR-2, PC50MR-2, and PC55MR-2 mini-excavator series. Serving as a critical pressure-safety component within the main hydraulic control valve, it directly determines the system's pressure stability, operational force, and the service life of hydraulic components.

The valve is precision-manufactured based on exact measurements of the original Komatsu multi-way valve cavity. Key specifications—including total body length, cartridge outer diameter, outlet positioning, external thread pitch, and seal groove depth—strictly match OEM standards. Installation is straightforward: the unit can be directly inserted and tightened without requiring secondary modifications to the control valve bore (such as reaming, grinding, or re-threading), ensuring a perfect fit for the compact hydraulic circuit layout of these MR-2 series excavators.

The valve body is CNC-machined from a solid bar of high-purity alloy structural steel. The mating surfaces of the spool and seat undergo a multi-stage hardening process—including high-frequency quenching, low-temperature tempering, and precision bore honing—resulting in superior surface hardness and exceptional resistance to wear and erosion. This robust construction withstands the high-pressure fluid surges and abrasive wear from microscopic contaminants typical of compact hydraulic circuits, effectively preventing common failures such as spool scoring, seal degradation, and persistent internal leakage. It provides a stable, reliable pressure-safety barrier for demanding, high-frequency operations in municipal mini-excavation, indoor demolition, and landscaping projects.

Packaging & Shipping

We use high-strength, environmentally friendly paper export packaging, which is reinforced, cushioned, and moisture-proof, suitable for long-distance international logistics transportation, and meets cross-border freight and environmental protection standards. International transportation adopts formal cross-border logistics, with full tracking of logistics information and supporting customs clearance documents to ensure smooth customs clearance and timely delivery of goods overseas.

Company Introduction

The GVO brand is a manufacturer of hydraulic components. We mainly produce the most comprehensive range of pilot pumps, gear pumps, relief valves, hydraulic pumps, electrical components, hydraulic parts, engine assemblies, traveling assemblies, rotating assemblies, distribution valves, and other components.

We are factory direct sellers without any middlemen profiting from price differences. The quality is definitely the best for you because we are the ones who produce them. We cannot tarnish our reputation. The prices are also the most favorable for you. There is a stable delivery speed.

We value every customer and provide you with the best service. We offer pre-sale, in-sale, and after-sale guarantees. Any problems will definitely be resolved for you. We are always available to serve you.