Jul 17: CFKS Expert Hydraulic Seals: Precision Sealing Solutions for Demanding Applications
Jul 16: CFKS Deepens Industry Expertise with High-Performance Washing Machine Seals
Jul 15: Understanding Bonded Seals: Structure, Function, and Applications
Jul 11: CFKS Expands Its Hydraulic Sealing Portfolio with High-Performance TG Oil Seals for Rotary Shaft Applications
CFKS SEALS Logo
Call (86) 188-3097-5917

Sealing Excellence, Securing Industry

CFKS NBR End Cap Oil Seal 10*4 Universal Rubber Covered End Cap Sealing Hydraulic End Covers
CFKS NBR End Cap Oil Seal 10*4 Universal Rubber Covered End Cap Sealing Hydraulic End Covers - Image 2
CFKS NBR End Cap Oil Seal 10*4 Universal Rubber Covered End Cap Sealing Hydraulic End Covers - Image 3
CFKS NBR End Cap Oil Seal 10*4 Universal Rubber Covered End Cap Sealing Hydraulic End Covers - Image 4

CFKS NBR End Cap Oil Seal 10*4 Universal Rubber Covered End Cap Sealing Hydraulic End Covers

The CFKS 10*4 NBR End Cap Oil Seal is an ultra-compact, universal static boundary component engineered for miniature power transmissions, small electric motors, and hydraulic end covers. By encapsulating a rigid internal carbon steel skeleton within a highly durable Nitrile (NBR) elastomeric jacket, this EC-style blind plug provides an absolute, interference-fit barrier. It securely seals precision casting bores at shaft termination points, preventing internal lubricants from weeping while actively excluding environmental dust and abrasive grit from breaching micro-bearing cavities.

  • Absolute Static Sealing: The fully rubberized 10mm outer diameter perfectly conforms to minor housing bore imperfections and easily absorbs high-frequency machine vibration.

  • Ultra-Compact 4mm Axial Profile: The slim 4mm width is explicitly optimized for shallow micro-housings where internal clearance between the plug and the rotating shaft end is virtually nonexistent.

  • Corrosion-Proof Exterior: The continuous elastomeric coating completely isolates the internal metal reinforcement, eliminating the risk of galvanic corrosion between the plug and aluminum or cast-iron housings.

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

Product Categories

Recent Posts

Brand Name CFKS OEM  Accpetable
Material NBR FKM Silicone  Features  wear resistance
Dimensions Customized Certificate  ISO9001/TS16949
Type EC Cap Seal  Packing 1 pc per bag

 

The structural integrity of this micro-end cover relies on precisely calculated radial interference. The internal metal skeleton provides the rigidity necessary to prevent the tiny 10mm cap from buckling under assembly load. Simultaneously, the elastomeric coating compresses firmly against the housing bore. Because rubber behaves as an incompressible fluid when confined, this compression forces the elastomer into the microscopic machining grooves of the casting, creating an absolute static lock. The shallow 4mm depth ensures the plug seals the bore completely without protruding too deeply into the housing and interfering with delicate internal rotating components.

This advanced formulation is explicitly engineered to handle long-term exposure to standard mineral-based gear oils, hydraulic fluids (HLP/HM), petroleum greases, and mild synthetic fluids at operating temperatures up to 100°C. The rubber jacket not only acts as an impenetrable fluid barrier but also functions as a permanent vibration dampener, ensuring the lightweight plug will not vibrate loose over the lifespan of the equipment.

Striking the center of the delicate 10*4mm cap will cause the internal metal skeleton to “dish” or cave inward. This deformation instantly pulls the outer diameter away from the bore wall, completely destroying the radial interference fit and guaranteeing an immediate static leak. Technicians must use a perfectly flat, parallel installation mandrel that distributes force evenly across the extreme outer edge of the seal. Wiping a very light film of system-compatible oil on the rubber OD prior to installation prevents the elastomer from binding or tearing against the housing chamfer during the press-fit operation.

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.

CFKS Seal Manufacturing Co., Ltd.
https://cfksseals.com/
 Email: cfksnacy@gmail.com  Mobile/WhatsApp/Wechat: (86) 188-3097-5917
EC End Cap Oil Seal Size List
TypeSIZE
EC End Cap Oil SealEC8*4
EC End Cap Oil SealEC10*4
EC End Cap Oil SealEC11*7
EC End Cap Oil SealEC12*4
EC End Cap Oil SealEC12*5
EC End Cap Oil SealEC14*4
EC End Cap Oil SealEC15*4
EC End Cap Oil SealEC15*5
EC End Cap Oil SealEC16*4
EC End Cap Oil SealEC16*5
EC End Cap Oil SealEC16*6
EC End Cap Oil SealEC18*4
EC End Cap Oil SealEC20*4
EC End Cap Oil SealEC20*5
EC End Cap Oil SealEC20*6
EC End Cap Oil SealEC20*7
EC End Cap Oil SealEC22*4
EC End Cap Oil SealEC22*4
EC End Cap Oil SealEC22*5
EC End Cap Oil SealEC22*5
EC End Cap Oil SealEC22*7
EC End Cap Oil SealEC23*4
EC End Cap Oil SealEC24*5
EC End Cap Oil SealEC24*5
EC End Cap Oil SealEC24*7
EC End Cap Oil SealEC24*7
EC End Cap Oil SealEC25*5
EC End Cap Oil SealEC25*6
EC End Cap Oil SealEC25*7
EC End Cap Oil SealEC25*7
EC End Cap Oil SealEC25*8
EC End Cap Oil SealEC26*4
EC End Cap Oil SealEC26*5
EC End Cap Oil SealEC26*6
EC End Cap Oil SealEC26*6
EC End Cap Oil SealEC26*7
EC End Cap Oil SealEC26*8
EC End Cap Oil SealEC27*5
EC End Cap Oil SealEC27*5
EC End Cap Oil SealEC28*4
EC End Cap Oil SealEC28*5
EC End Cap Oil SealEC28*5
EC End Cap Oil SealEC28*6
EC End Cap Oil SealEC28*7
EC End Cap Oil SealEC28*8

 

MESSAGE

Bonded Seal (22) BS Seal (3) Cassette Oil Seal (3) Combi Oil Seal (3) Construction Seal (9) Coupling Spider (17) DAS Seal (3) DH Seal (4) DHS Seal (3) DK/DP Seal (3) DLI Seal (3) EC Cup Seal (13) Glyd Ring (5) Guide Ring (16) HBY Seal (2) High Pressure Water Seal (37) Hydraulic Oil Seal (161) IDU Seal (7) JA Seal (5) J Type Seal (5) LBH Seal (2) LBI Seal (2) O-Ring/O-Ring Kit (12) ODU Seal (8) OK Seal (3) OUY Seal (3) Piston Seal (25) Polyurethane Bump Stop (6) Polyurethane Washer (3) Power Transmission Parts (26) Rod Seal (49) Rotary Shaft Oil Seal (40) Split Oil Seal (4) Split Rotary Shaft Seal (3) Spring Energized Seal (3) Stainless Steel Oil Seal (3) Step Seal (3) TBV (20) TC/TG Seal (101) TCV/TCN (10) UHS Seal (3) UN/USH/UPH Rod Seal (21) VA/VS Seal (3) Washing Machine Seal (12) Wiper Seals/Dust Seal (36)

Recently New Seals

View New Products Get Support

Follow Us

Get a Quote or Ask a Question

NAVIGATION

CFKS PRODUCT RANGE

CONTACT US

© CFKS Seals Manufacturing Co., Ltd. All Rights Reserved

Go to Top