High Performance UN Seal for Hydraulic Rod Systems U-cup Seal Manufacturer

In hydraulic equipment and industrial automation systems, the stability of the
entire system depends on various factors. However, there is one component that
requires low investment and is easy to replace—this is the UN-type rod seal we
are going to explore today.

What is a UN Seal?

UN seal (also known as a U-cup or U-type seal) is a versatile sealing component
that can be installed on either piston rods or pistons. It features a
distinctive “U” shaped profile, with both the inner and outer sealing lips
specifically designed to optimize sealing performance in rod and piston
applications.

Material Selection and Structural Advantages

To meet diverse sealing demands across different working conditions, DEDE
offers this series in two material options: Polyurethane (PU) and Fluororubber
(FKM).

PU Material: Often referred to as the “fifth engineering plastic,”
polyurethane combines the elasticity of rubber with the durability of plastic.
It offers excellent wear resistance, tear strength, and chemical stability.
Even under high-frequency motion and low compression set conditions, it
maintains reliable sealing performance. With an operating temperature range of
-20°C to +120°C, PU seals are well-suited for variable outdoor and industrial
environments.

FKM Material: Known for its exceptional resistance to high temperatures and
oils, FKM is ideal for harsh chemical environments and high-temperature, high-
pressure conditions. It is particularly suitable for high-vacuum systems, oil-
filled systems, or applications requiring stringent media compatibility—such
as hydraulic pumps and turbine sealing systems.

Key Features and Application Adaptability

The UN-type rod seal series offers the following advantages:

High compatibility with both dynamic and static sealing in medium to high-
pressure hydraulic systems;

Precision lip design ensures low friction and stable oil return;

Automatically enhances sealing performance as pressure increases, preventing
leakage;

Can be used in conjunction with dust wipers to significantly extend system
lifespan.

Thanks to these advantages, UN-type rod seals have become vital components in
ensuring long-term operational stability across a wide range of equipment,
including industrial hydraulic cylinders, automotive hydraulic power steering
systems, electromechanical arms, and agricultural machinery hydraulic systems.

Application Industries

Construction Machinery: Hydraulic cylinder sealing systems in excavators,
bulldozers, etc.;

Automation Equipment: Sealing control at actuator ends in robots and mechanical
arms;

Industrial Equipment: Hydraulic presses, punching machines, CNC machinery;

Automotive Industry: Rod seals used in power steering and transmission systems;

Energy Equipment: Hydraulic regulation systems in wind power installations.

By continuously optimizing material selection and refining manufacturing
processes, DEDE has ensured that the UN series offers outstanding durability
and low maintenance costs.

DEDE's Service and Technical Support

With over 30 years of manufacturing experience, DEDE is a well-established
sealing systems provider with its own production facilities and a global supply
and service network spanning more than 80 countries. Our key service strengths
include:

Fast delivery of standard parts: Covering tens of thousands of specifications
to quickly meet customer demands;

Customized sealing solutions: End-to-end services from structural design and
material formulation to on-site testing;

Sealing performance optimization: An experienced engineering team helps
customers reduce maintenance frequency and extend service life.

Additionally, DEDE is recognized as a provincial-level "Specialized and
Innovative" enterprise and a national high-tech enterprise, making it a
benchmark brand in intelligent manufacturing and technological innovation
within the sealing industry.

Why Choose DEDE’s UN Seal Series?

Though small in size, sealing components are critical to the stable operation
of systems. In high-frequency motion, high-pressure circuits, and harsh
chemical environments, DEDE’s UN seal series delivers outstanding performance
and versatile applicability—offering solid protection for reliable equipment
operation. We don’t just sell seals—we deliver dependable sealing solutions.

If you’re facing complex sealing challenges, feel free to contact us for
technical advice or customized solutions.

Minimum Order: 500 pieces

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