dbde24e1-4012-47b6-8db4-e89ee4ca5a70 - Polypac

English

Turkish

dbde24e1-4012-47b6-8db4-e89ee4ca5a70

Polypac U-Cup Seal Category — Advanced Hydraulic Seals

Polypac U-Cup Seal Solutions — Reliable Sealing for Hydraulic Systems

Overview of U-Cup Seal Technology

The U-Cup Seal is a proven axial sealing element widely used in hydraulic cylinders and reciprocating applications. Polypac's U-Cup Seal series combines intelligent geometry with advanced materials to provide consistent sealing, low breakaway friction, and extended service life. Designed for both dynamic and static service, our U-Cup Seal options solve leakage and wear challenges across industries.

Design & Functionality

U-Cup Seals feature a U-shaped profile that enhances lip conformity under pressure, creating a reliable sealing interface that adapts to cylinder movement. Polypac engineers optimize lip thickness, support elements, and backup ring compatibility to balance sealability and friction. The result is stable performance under pressure spikes, temperature swings, and media variations.

Materials & Performance

Leveraging our heritage in filled PTFE and advanced elastomers, Polypac offers U-Cup Seal materials including bronze-filled PTFE, carbon-filled PTFE, MoS2 and graphite blends, as well as NBR, FKM, EPDM, silicone and FFKM elastomers. Material selection is matched to fluid compatibility, temperature range, and wear resistance to ensure superior life in hydraulic oils, aggressive media, and harsh environments.

Customization & Manufacturing Capacity

Founded in 2008, Polypac operates a custom rubber ring and O-ring factory covering over 10,000 m² with 8,000 m² production space. Our advanced production and testing equipment enable bespoke U-Cup Seal designs for special working conditions, tight tolerances, and high-volume programs. We collaborate with universities and research institutions to develop tailored sealing solutions.

Quality Assurance & Testing

Every U-Cup Seal undergoes rigorous dimensional, material and functional testing to meet international standards. Polypac's QC processes include tensile, hardness, leakage and endurance tests, ensuring reliable performance in demanding hydraulic and pneumatic systems.

Applications & Why Choose Polypac

Polypac U-Cup Seals are ideal for hydraulic cylinders, actuators, mobile equipment, and heavy machinery. With deep expertise in seal development and a broad material portfolio, Polypac delivers cost-effective, high-performance U-Cup Seal solutions backed by technical support and fast lead times. Contact Polypac to specify custom U-Cup Seals for your application.

U-Cup Seal Display

FAQ:

How important is surface finish on the metal parts that contact the seal?

Extremely important. A rough surface will abrade and wear out the seal quickly, causing leaks. A finish that is too smooth can prevent a lubricating film from forming. A typical recommended surface finish for dynamic applications is 0.2 to 0.8 μm (8-32 μin) Ra.

What is the difference between a static seal and a dynamic seal?

A Static Seal is used between two surfaces that do not move relative to each other (e.g., pipe flanges, end caps). O-rings and gaskets are common static seals. A Dynamic Seal is used between surfaces that do move (e.g., piston and cylinder, rotating shaft). Rod seals, piston seals, and rotary shaft seals are designed for this purpose.

How can I prevent seal damage during installation?

Use Tools: Always use dedicated installation tools (e.g., picks, cones, guides). Lubricate: Always lubricate the seal and the contact surface. Protect Sharp Edges: Cover sharp threads and edges with tape or use an installation sleeve. Check the Groove: Ensure the installation groove is clean, deburred, and undamaged.

Can I reuse a seal?

We strongly recommend never reusing seals. Once compressed and used, a seal takes a "set" and its elastic properties are degraded. Reusing it almost always results in a leak. Always install a new seal during any maintenance or repair.

What does "AS568" mean?

AS568 is the Aerospace Standard that defines the dimensions for over 360 standard O-ring sizes. It is the most widely accepted sizing system in North America and globally. An AS568 number (e.g., AS568-214) specifies a precise inside diameter and cross-section.

Table of Contents

≡

Polypac U-Cup Seal Solutions — Reliable Sealing for Hydraulic Systems
Overview of U-Cup Seal Technology
Design & Functionality
Materials & Performance
Customization & Manufacturing Capacity
Quality Assurance & Testing
Applications & Why Choose Polypac
U-Cup Seal Display

Related Blog

Dust Seals: The Essential First Line of Defense for Your Machinery | Polypac

Polypac’s Dust Seals provide the essential first line of defense for your machinery. Our custom seals ensure superior protection against dust and debris, enhancing equipment longevity. Trust Polypac for reliable, high-quality protective seals tailored to your needs.

Dust Seals: The Essential First Line of Defense for Your Machinery | Polypac

O-Rings: The Complete Guide to This Universal Sealing Solution | Polypac

Discover Polypac’s comprehensive guide to O-Rings, the universal sealing solution. Explore key materials like NBR and FKM for optimal performance in diverse applications. Learn how our expert insights ensure reliable, durable seals tailored to your industrial needs.

O-Rings: The Complete Guide to This Universal Sealing Solution | Polypac

Back-up Rings: The Essential Guard Against Seal Extrusion | Polypac

Polypac’s Back-up Rings are essential for preventing seal extrusion and maintaining seal integrity in high-pressure applications. Discover how our durable solutions protect your seals, ensuring long-lasting performance and reliability in industrial environments. Trust Polypac for superior sealing protection.

Back-up Rings: The Essential Guard Against Seal Extrusion | Polypac

Wiper & Dust Rings: The First Line of Defense for Hydraulic Cylinders | Polypac

Polypac’s Wiper & Dust Rings protect hydraulic cylinders by preventing contaminants from entering, ensuring optimal performance and longevity. As the first line of defense, these seals maintain system integrity, reduce wear, and enhance reliability for all hydraulic applications.

Wiper & Dust Rings: The First Line of Defense for Hydraulic Cylinders | Polypac