100% Japan Factory OUY 40x25x12 NBR Material Hydraulic Cylinder Oil Seal For Construction Machinery And Equipment

The above photos are actual photos taken.

Manufactured with 100% authentic Japanese factory craftsmanship and standardized precision processing procedures. It strictly conforms to the standard dimension of 40×25×12 with zero dimensional deviation and structural deformation. The oil seal features integral molding and smooth, uniform sealing lips, which perfectly matches the mounting grooves of hydraulic cylinders for construction machinery. It delivers high assembly adhesion and effectively prevents oil leakage, jamming and falling-off caused by dimensional mismatch, offering superior compatibility compared with ordinary general-purpose oil seals.

Adopting high-purity NBR nitrile rubber material, this oil seal boasts outstanding resistance to mineral oil, hydraulic oil and lubricating oil. It will not swell, soften, crack or age even after long-term contact with hydraulic media. Designed for standard hydraulic working conditions of construction machinery, it maintains stable performance within a wide temperature range of -40℃ to 120℃, adapting to complex outdoor working environments with alternating high and low temperatures. It also features excellent anti-corrosion performance to resist erosion from impurities and oil sludge in hydraulic systems.

Featuring a professional OUY piston sealing structure with high structural strength and superior pressure resistance, the oil seal stably withstands high-frequency and high-pressure impacts of hydraulic systems. It is perfectly applicable to heavy-duty equipment including excavators, loaders and tower cranes. The high-toughness NBR material with low wear resistance coefficient resists continuous friction caused by reciprocating piston movement, effectively reducing long-term wear rate, extending service life and minimizing equipment downtime.

Equipped with an optimized lip sealing structure with tight fitting and excellent resilience, it achieves zero leakage under both static standby and dynamic operating conditions. It stably locks hydraulic oil to prevent cylinder pressure loss, oil leakage and insufficient power, ensuring constant hydraulic system pressure. Meanwhile, it effectively blocks external dust, sediment, moisture and metal debris from entering the cylinder, avoiding hydraulic oil contamination, cylinder wall wear and valve core jamming, which fully protects core hydraulic cylinder components.

Adopting Japan original modified NBR formula, the oil seal delivers enhanced anti-aging, anti-fatigue and anti-deformation capabilities. It maintains stable elasticity and structural integrity under frequent start-stop operation, reciprocating movement and vibration impact of construction machinery, without looseness, hardening, deformation or elastic attenuation. Compared with ordinary oil seals, it greatly improves fatigue resistance, reduces operation and maintenance costs and achieves higher comprehensive cost performance.

Before disassembly, completely shut down the equipment and release system pressure, and wait until the hydraulic oil temperature drops to normal temperature to avoid scalding risks and safety hazards caused by pressured disassembly. Mark the installation positions of oil pipes and cylinder end covers in advance, and block the pipe interfaces with special plugs after disassembly to prevent dust and impurities from entering the oil circuit. Loosen the end cover bolts evenly and remove the end cover slowly. Never strike or pry violently to avoid scratching the precision surfaces of the piston rod and cylinder wall. Finally, pull out the piston assembly steadily and remove the worn and damaged old oil seal.

Before installing the new oil seal, thoroughly clean oil sludge, metal debris and burrs on the cylinder sealing grooves, inner cylinder wall and piston rod surface to ensure the mounting surface is clean, flat and scratch-free. Strictly verify the new oil seal model, confirm the specification is 40×25×12, material is NBR and type is OUY. Inspect the oil seal for no deformation, cracking, material deficiency, aging or impurities. Meanwhile, check the size and surface roughness of cylinder sealing grooves to avoid sealing failure caused by groove wear and deformation.

Evenly coat the oil seal lips and overall surface with clean matched hydraulic oil before installation to increase lubrication, reduce assembly resistance and prevent lip damage and deformation from dry installation. Use professional oil seal tools for steady pressing installation. Keep the oil seal vertical and horizontal during assembly. Avoid inclined installation, violent pressing or prying with screwdrivers to prevent torsion, flanging and lip breakage. Ensure the oil seal is fully embedded in the sealing groove without offset, suspension or wrinkles. Push the piston manually after installation to confirm flexible movement without jamming.

Reset the cylinder end cover and oil pipes after installation, and tighten the fixing bolts diagonally and evenly to ensure uniform stress and tight sealing. Conduct low-speed no-load trial operation to check smooth cylinder telescoping without abnormal noise and no oil leakage or pressure drop at the sealing position. Gradually increase the system pressure to the rated working pressure and keep running for 10 to 15 minutes. Confirm stable pressure and zero leakage before putting the equipment into formal heavy-duty operation.

Regularly inspect the cylinder sealing parts during daily operation. Minor oil leakage, pressure attenuation or slow cylinder movement usually indicates lip wear or elastic attenuation, which requires timely shutdown inspection and replacement to avoid fault escalation. Avoid long-term overload and overpressure operation to reduce high-pressure fatigue loss of the oil seal. Replace hydraulic oil and clean filter elements regularly to prevent impurities from wearing the seal lips. Store spare oil seals in cool and dry environments, avoiding direct sunlight, high temperature, extrusion deformation and contact with acid-base corrosive substances to retain original factory performance.

Guangzhou upseal technology co., ltd

Guangzhou upseal technology co., ltd originated from the original Guangzhou Huaxing Oil Seal Company, engaged in international well-known brands of original imported oil seal seals and construction machinery repair kits, set product sales, brand agents, technical support and after-sales service in one company. Focus on the machinery industry market has more than 20 years of history, long-term for the construction machinery industry, metallurgy industry, shipping industry, air compressor industry, automotive industry, hydraulic cylinder factory, marine machinery, mining equipment machinery, electrical machinery and other industries to provide professional solutions. We are committed to the "camp superior products, reputation first" purposes for customer service, to provide customers with more sealed products and competitive prices, the company has a strong product database, inventory of 50 million.

Inventory: generally 1-3 days. Out of stock: 3-7 days after sample confirmation. Order: 10-30 days after payment, confirm the delivery time of the product according to the quantity.

Yes, we can provide samples, but we need to pay the cost and shipping cost.

Quality comes first. We attach great importance to quality control from start to finish: B: Skilled workers pay great attention to every detail in the production and packaging process;

A:. Re-check the product before shipping to make sure our packaging is intact B: Track and receive customer feedback

Yes, we accept OEM and ODM for our customers.

We can accept EXW, FOB, CIF, etc. You can choose the most convenient one.

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