Sealing Excellence, Securing Industry

CFKS High Pressure Water Pump Sealing Ring 18*28*6 U-Cup Seal NBR Water Sealing Gasket for Industrial

The CFKS 18*28*6 NBR U-Cup Water Seal is a high-performance dynamic sealing gasket engineered specifically for heavy-duty industrial water pumps and pressure washing systems. Utilizing a pressure-energized asymmetrical profile, this precision-molded elastomeric ring ensures absolute fluid containment along reciprocating plungers and rotary shafts, preventing catastrophic water bypass into critical mechanical drive components.

  • Pressure-Energized Geometry: The U-cup profile actively harnesses system pressure to maintain a leak-free hydrodynamic boundary layer.

  • Aqueous Media Optimized: High-density Nitrile (NBR) formulation resists waterborne abrasives and standard industrial cleaning detergents.

  • Precision 18*28*6mm Fit: Manufactured to exacting dimensional tolerances for a secure, drop-in replacement in standard pump manifolds.

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

Brand Name CFKS OEM  Accpetable
Material NBR FKM Silicone  Features  wear resistance
Dimensions Customized Certificate  ISO9001/TS16949
Type 18*28*6 High Pressure Water Seal  Packing 1 pc per bag

 

The fundamental mechanical advantage of the CFKS U-Cup Water Seal lies in its pressure-proportional hydrodynamic design. Unlike standard rotary lip seals that rely purely on a mechanical garter spring, the asymmetrical U-cup profile actively harnesses the internal fluid pressure of the pump. As water enters the volute, it fills the open “U” cavity, physically expanding the elastomeric lips radially. The dynamic inner lip creates a high-unit load against the 18mm shaft or plunger, while the static outer lip anchors securely against the 28mm housing bore. This ensures that the sealing force increases exactly in proportion with system pressure spikes, effectively preventing fluid blow-by without inducing excessive friction and heat during low-pressure bypass modes.

In demanding industrial fluid transfer applications, standard commercial rubbers frequently suffer from hydrolysis or rapid abrasive wear. Our 18*28*6mm sealing gaskets are injection-molded from a highly cross-linked, high-density Nitrile Butadiene Rubber (NBR) specifically formulated for aqueous environments. Operating efficiently in fluid temperatures up to 90°C, this specialized NBR matrix provides exceptional tear strength and elasticity. It easily withstands the localized cavitation and micro-particulate abrasion typical in industrial water pumps, while actively resisting the chemical degradation caused by standard alkaline soaps and descaling agents injected into the fluid stream.

From a maintenance engineering perspective, meticulous installation is paramount to achieving a long, low-friction service life. The robust 6mm cross-section of the NBR U-cup allows for a straightforward, snap-in installation into standard pump glands. However, technicians must ensure the mating shaft or ceramic plunger is polished to a surface finish of 0.2 to 0.4 μm Ra to prevent the new elastomeric lip from being shredded by microscopic grooving. Crucially, applying a light coating of silicone-based assembly grease to the dynamic lip prior to startup is mandatory. This prevents the destructive “dry-rub” galling that causes immediate thermal degradation before the pump is fully primed with water.

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
High Pressure Water Seal Size List
TypeSIZETypeSIZE
v type18*30*5.5U type15*22*5
v type18*28*5.5U type15*24*5
v type18*32*6U type18*26*5
v type20*32*5.5U type18*28*6
v type20*28*5.5U type20*28*5.7
v type22*28*5.5U type20*30*6
v type16*24*5.5U type28*36*5.9
v type15*25*5.5U type28*38*5.9
v type18*35*7U type22*30*6
v type14*26*5U type12*20*5
v type22*32*.5U type14*22*5
v type18*26*5.5U type18*24
v type20*35*5.5U type25*37*6.4
v type18*35*7U type13*20*5
v type18*32*7U type14*20*5
v type20*30*6U type16*24*5.5
v type20*35*7U type18*25*5
v type18*30*6U type20*35*6
v type24*35*6U type24*34*6
v type15*28*5U type18*25*5
v type18*32*5.5U type18*28*6
v type12*20*5U type18*26*6
v type12*22*5.5U type22*32*5.5
v type18*32*7.1U type18*26*5

MESSAGE

Go to Top