4392196 4613559 14597185 14622932 4674564 Excavator EX400-5 EX450H-5 EX550-5 Main Relief Valve Pressure Relief Valve

4392196 4613559 14597185 14622932 4674564 Excavator EX400-5 EX450H-5 EX550-5 Main Relief Valve Pressure Relief 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 cartridge-type main relief valve is a core pressure safety protection component in the hydraulic system of Hitachi EX-5 series medium and large heavy-duty excavators. It precisely corresponds to the main gun position installation dimensions of the distribution valve in the EX400-5, EX450H-5, and EX550-5 classic mining-grade models. As the ultimate pressure regulating and overload protection device for the entire machine's hydraulic circuit, it directly determines the overall hydraulic pressure stability and the service life of major hydraulic components.

The valve body is integrally forged from high-grade alloy structural steel, eliminating the defects of ordinary aftermarket cast iron parts that are prone to high-pressure cracking and long-term pressure deformation. It undergoes multiple precision machining processes, including full-size precision cutting on a CNC lathe, high-precision external cylindrical grinding, and diamond honing of the valve sleeve inner bore. The clearance between the valve core and valve sleeve is controlled within micron-level precision tolerances, minimizing internal leakage under high pressure and eliminating common industry problems such as pressure loss, pressure drift, and soft pressure relief.

All pressure-bearing components undergo a dual strengthening process of tempering heat treatment followed by surface carburizing and quenching, resulting in uniform overall hardness and significantly improved resistance to high-frequency impact and fatigue creep. Even under repeated opening and closing at rated working pressures above 32MPa, issues such as valve core jamming, thread stripping, and seal groove deformation will not occur.

The external adjusting locking nut features a thickened hexagonal reinforced structure, ensuring even wrench force during pressure adjustments and preventing slippage and failure to lock due to sharp edges. The valve stem outlet has a smooth, chamfered flow path optimization, resulting in low hydraulic oil flow resistance and preventing localized throttling back pressure.

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.