352-7113 Main Relief Valve Pressure Relief Valve Safety Valve E320D 324D 325D

Product Specification

352-7113 Main Relief Valve Pressure Relief Valve Safety Valve E320D 324D 325D 329D 330D 340DL 320D2 336D2 Excavator Parts

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 dedicated pressure protection accessory for the main cannon of the classic direct-injection D-series medium and large excavators. It offers one-stop compatibility with six benchmark models with large market presence: E320D, 323DL extended chassis version, 324D, 325D, 329D, and 330D. It is precisely replicated 1:1 according to the original factory specifications for valve bore inner diameter, thread pitch, insertion depth, valve core stroke, and internal pressure regulating structure. The valve bore is completely interchangeable across all six models, making it an irreplaceable ultimate overload pressure relief safety barrier for the D-series hydraulic system.

The entire valve body is forged from a single piece of high-toughness alloy structural steel, completely eliminating the inherent fatal defects of inferior aftermarket cast iron valve bodies, such as easy cracking under high pressure, slight deformation under long-term high-frequency reciprocating loads, and easy erosion and scoring of the sealing surface by high-speed, high-pressure oil.

The valve core, valve sleeve, and valve body—all core pressure-bearing components—undergo three rigorous precision machining processes: full-size integrated precision cutting on a CNC lathe, high-precision centerless grinding of the outer diameter, and diamond ultra-precision honing of the valve sleeve inner bore. The clearance between the valve core and valve sleeve is controlled within micron-level ultra-precision tolerances, minimizing internal oil leakage under high-pressure conditions. This fundamentally solves common industry problems such as pressure regulation drift, insecure locking, and weak or ineffective instantaneous pressure relief under heavy loads.

The valve is equipped with imported high-pressure resistant fluororubber O-rings, possessing excellent resistance to mineral hydraulic oil corrosion, high-temperature long-term aging, and non-hardening and brittleness at low temperatures. Even under harsh conditions such as continuous full-load operation for over ten hours a day at 330°C with soaring oil temperatures and drastic temperature fluctuations in open-pit mines, the sealing performance remains reliable and durable, eliminating the risk of oil leakage, dripping, or internal pressure drop on the valve body.

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.