GVO 723-10-11301 Main Pressure Relief Valve Action Control Valve PC20R-8 PC27R-8

Product Specification

GVO 723-10-11301 Main Pressure Relief Valve Action Control Valve PC20R-8 PC27R-8 D31ex D37px D39ex 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-style relief valve is a universal hydraulic pressure protection component for various Komatsu models. It is perfectly suited for the PC20R-8 and PC27R-8 (new-generation 2–3 ton class mini-excavators) and is also compatible with the hydraulic control systems of D31EX, D37PX, and D39EX series compact bulldozers. It serves as a critical, high-wear component within the hydraulic circuit, responsible for limiting maximum pressure, unloading overloads, and stabilizing system pressure.

The sealing assembly and external structural design have been engineered to withstand the harsh operating conditions typical of mini-excavators—such as confined engine compartments, poor heat dissipation, high summer oil temperatures, exposure to mud and water splashes, and frequent vibrations from travel over rough terrain. Comprehensive upgrades have been implemented to enhance sealing performance, weather resistance, and vibration tolerance. The valve body features a red limit ring at the top paired with a high-temperature-resistant fluororubber (FKM) O-ring; this combination ensures long-term resistance to corrosion from degraded hydraulic fluid and prevents hardening, cracking, or aging failures caused by rapid temperature fluctuations.

The threaded mounting section is fitted with a thickened, oil-resistant nitrile rubber (NBR) pressure-resistant seal. This dual-sealing configuration effectively prevents high-pressure hydraulic fluid leakage. Even during continuous operation in rainy, muddy conditions, dusty demolition sites, or damp basements, the valve remains leak-free at the interface with the valve block and along the threaded connections.

The mounting threads are produced using a precision thread-rolling process, resulting in a full, uniform thread profile that ensures smooth installation into the control valve cavity without cross-threading or stripping the valve port. The multi-step locking hex nut at the rear distributes stress evenly, ensuring the valve body remains securely fastened despite the constant vibrations caused by frequent steering and travel over rough ground, thereby eliminating pressure drift or instability caused by long-term vibration.

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.