Sealing Excellence, Securing Industry

CFKS DLI Oil Seal 50*65*7.5 Hydraulic DLI Type Oil Seal NBR DLI Skeleton Dust Seal

The CFKS DLI 50*65*7.5 hydraulic oil seal is an engineered, heavy-duty axial sealing solution designed to protect critical machinery from severe external contamination while retaining internal lubricants. Combining a robust metal skeleton with an optimized elastomeric sealing lip, this DLI-type dust seal ensures dynamic stability in high-pressure hydraulic cylinders and reciprocating shafts.

  • Dual-Lip Protection: Integrated dust lip and primary sealing lip effectively block ingress while preventing oil leakage.

  • Premium Elastomer Compounds: Available in high-grade NBR and FKM to withstand extreme thermal and chemical environments.

  • Precise Dimensional Fit: Exact 50mm*65mm*7.5mm engineering guarantees a secure, press-fit installation without housing deformation.

Find your sealing solution with CFKS — contact us for a quote.

Product Name CFKS DLI Oil Seal 50*65*7.5 Specification 50mm*65mm *7.5mm
Material NBR / FKM / PU Feature High Pressure & Severe Wear Resistance
Work Temperature -20℃ to 220℃ Hardness 70 – 90 Shore A
Type DLI Skeleton Dust Seal Usage Hydraulic Cylinders, Excavators, Pumps, Valves, Forging Presses, Agri-machinery

The DLI type oil seal operates on an advanced axial sealing principle designed to counteract severe radial runout and centrifugal force. The internal metal skeleton provides structural rigidity, ensuring that the elastomer lip maintains constant, uniform radial pressure on the rotating or reciprocating shaft. As the shaft moves, the secondary dust lip creates a narrow fluid-film barrier that repels external debris, while the primary sealing lip utilizes hydrodynamic action to pump migrating oil back into the lubrication chamber, minimizing friction and wear.

Material integrity is paramount in demanding hydraulic environments. CFKS utilizes specialized NBR and FKM compounds to match specific media compatibility. Standard NBR variants offer exceptional resistance to petroleum based hydraulic oils, mineral oils, and water-glycol fluids, making them ideal for general industrial applications. For high temperature setups or aggressive chemical media, our FKM compound provides superior resistance to thermal degradation, ozone, and synthetic lubricants, preventing premature hardening and cracking.

Minimizing equipment downtime requires a sealing design that simplifies field replacement. The CFKS DLI profile is engineered for straightforward press-fit installation into standard ISO housing grooves. The flexible elastomer outer diameter compensates for minor housing imperfections, preventing fluid bypass. Due to the optimized lip geometry and low-friction material compounding, this seal exhibits an extended service life with minimal heat generation, significantly reducing the frequency of scheduled maintenance overhauls.

Frequently Asked Questions (FAQ)

Why does my CFKS oil seal fail prematurely? Common causes and prevention tips2025-06-26T15:44:39+08:00

Premature oil seal failure can result from improper installation, poor shaft finish, incorrect material selection, or excessive pressure. To prevent this, ensure the shaft surface is smooth and within tolerance, use correct tools during installation, and choose seals made from materials compatible with your media and temperature.

How to correctly install a CFKS industrial oil seal to avoid leakage2025-06-26T16:04:32+08:00

Always clean the shaft and bore before installation. Use appropriate seal drivers to avoid deformation. Lubricate the lip before fitting to reduce friction during the first rotation. Ensure the seal is seated evenly and not tilted to avoid leaks.

What to do when your CFKS hydraulic seal is leaking under pressure2025-05-20T16:33:14+08:00

Check if the pressure exceeds the seal’s rated limit. Examine for wear, hardening, or improper installation. Replace the seal if damaged, and consider upgrading to a high-pressure CFKS seal variant. Also, verify that the housing and shaft are properly aligned.

How to choose the right CFKS oil seal for extreme operating environments2025-05-20T16:34:39+08:00

For high temperatures, aggressive chemicals, or abrasive environments, choose CFKS seals made of FKM, PTFE, or high-performance elastomers. Consider using seals with protective dust lips or metal casing. Our team can recommend the best fit for your application.

MESSAGE

Go to Top