Manufacturer of Rubber Sealing Strips & Custom Molded Parts | OKIN Seal
As the core sealing division of Taiwan Okin Huasu Group, OKIN Seal is a premier manufacturer specializing in rubber sealing strips and custom molded rubber parts with over 20 years of industrial experience. We operate advanced production lines for both extrusion and molding processes, ensuring consistent quality for water & air tightness, sound insulation, and vibration damping applications.
Our extensive product range includes rubber seal strips, edge trims, composite extrusions, and various molded rubber gaskets. These components are widely used in multiple sectors, including automotive, construction (doors & windows), marine containers, rail transit, heavy machinery, and new energy equipment, meeting strict performance standards.
OKIN Seal provides supporting rubber components for global industrial projects with full OEM and ODM capabilities. From raw material formula design to final manufacturing, we offer multiple performance options such as flame retardancy (UL94) and corrosion resistance. We are committed to delivering cost-effective rubber sealing solutions that improve safety and durability. Partner with OKIN Seal for your custom sealing needs.
Global Export Markets & Strategic Partnerships
OKIN Seal serves a vast international market, with premium rubber products exported to over 50 countries across Europe, North America, Southeast Asia, and the Middle East. As a trusted global supplier, we have established long-term collaborations with both renowned international enterprises and domestic industry leaders, including Moser Windows, FAW Group, Great Wall Motors, and Conch Group. With strict quality control and dependable performance, we have earned the recognition of customers worldwide.
Certifications & Quality Mission
OKIN Seal’s manufacturing facilities are fully certified to IATF 16949, ISO 9001, and ISO 14001 standards, demonstrating our commitment to international automotive and environmental protocols. To maintain these high standards, we adhere to a strict “100% Virgin Material” policy, sourcing premium raw materials exclusively from global leaders like Dow, ExxonMobil, and Lanxess. Our sealing strips have also passed rigorous VOC emission testing, ensuring full compliance with OEM interior air quality requirements.
Okin Seal Teams
Certification
Advanced Manufacturing & Process Control
We control quality from the source. Our material mixing center ensures precise dispersion of raw materials to achieve consistent Shore A hardness and superior physical properties. From in-house mold development to final vulcanization, every step is optimized for low compression set, tight tolerances, and excellent weather resistance.
Precision Internal Compounding
Refined Open Milling
In-House Mold Engineering
Precision Vulcanization Press
Mold Tooling Inventory
Microwave Curing Extrusion Line
Continuous Vulcanization Process
Metal Skeleton Roll Forming
Injection Corner Splicing
Precision Punching & Drilling
Standard Operating Procedures（SOP）
CNC Mold Machining Center
UL94 Flammability Tester
Tensile Strength & Elongation Tester
Automated Compounding Control System
Moving Die Rheometer (MDR)
Custom Formula R&D Capabilities
Our in-house laboratory specializes in developing custom rubber formulations to meet specific ASTM, SAE, and ISO standards. We strictly use 100% virgin materials (RoHS/REACH compliant) to ensure optimal performance. Custom compounding options include UL94 Flame Retardant, High-Conductivity, and Extreme Temperature Resistance.
Rubber Material
EPDM Rubber
Temperature Range: -40°C to +150°C
Key Properties: Excellent weather, Ozone, and UV resistance. Superior resistance to steam and water. High elasticity with low compression set.
Best For: Outdoor sealing strips, automotive weatherstrips, window gaskets, and marine applications.
CR Rubber
Temperature Range: -40°C to +100°C
Key Properties: Balanced performance. Good resistance to oils, chemicals, and weathering. Inherently flame retardant (self-extinguishing).
Best For: General-purpose seals, HVAC gaskets, and flame-retardant applications.
NBR
Temperature Range: -30°C to +120°C
Key Properties: Excellent oil and fuel resistance. Good mechanical properties and abrasion resistance.
Limitations: Poor resistance to Ozone and sunlight (not recommended for direct outdoor exposure).
Best For: Fuel system seals, oil hoses, and machinery gaskets.
Natural Rubber(NR)
Temperature Range: -50°C to +70°C
Key Properties: Outstanding elasticity and abrasion resistance. Exceptional tensile strength and vibration dampening capabilities.
Best For: Vibration isolators, shock mounts, and heavy-duty dynamic parts.
Silicone Rubber
Temperature Range: -60°C to +230°C
Key Properties: Extreme temperature flexibility. Non-toxic, odorless, and chemically inert. Excellent UV and color stability.
Best For: High-temperature seals, food/medical grade applications, and aesthetic parts.
Plastic Material
TPE (Thermoplastic Elastomer)
Temperature Range: -40°C to +135°C
Key Properties: Eco-friendly and Recyclable. Combines the processing advantages of plastics with the elasticity of rubber. Easy to color-match.
Best For: Automotive window encapsulation, consumer grips, and recyclable sealing profiles.
PVC (Polyvinyl Chloride)
Temperature Range: -20°C to +70°C
Key Properties: Cost-effective. Good chemical resistance and inherent flame retardancy. High rigidity options available.
Best For: Economic edge trims, door bottoms, and rigid-flexible co-extrusions.
Precision Extrusion Technology
Our advanced polymer extrusion lines are designed to produce complex profiles with tight tolerances. Whether you need solid, sponge, or dual-durometer (co-extruded) profiles, we can process a wide range of materials including EPDM, NBR, CR, and Silicone. Instead of standard “off-the-shelf” products, we specialize in custom-engineered profiles that offer superior sealing performance and durability.
Microwave Vulcanization & Curing
We utilize state-of-the-art Microwave Curing Systems and High-Velocity Hot Air tunnels to ensure uniform vulcanization from the inside out. Unlike traditional methods, this continuous process guarantees a smoother surface finish, higher dimensional stability, and rapid production speeds for high-volume orders. Our process is optimized to prevent porosity and ensure consistent physical properties across every meter of the sealing strip.
Value-Added Fabrication Services
Our capabilities go beyond basic extrusion. With our dedicated finishing workshop, we transform profiles into “ready-to-install” components.
Hot Vulcanized Splicing: (As shown) We utilize precision molding presses to create seamless, high-strength bonded corners. This ensures 100% water and air tightness at critical joints.
Custom Detailing: We offer precision cutting, drilling, and notching services to meet exact assembly requirements.
Adhesive Taping: Application of pressure-sensitive adhesive (PSA) tapes (e.g., 3M, Sony) for easy peel-and-stick installation
Manufacturing Tolerance
We strictly adhere to international dimensional standards to ensure seamless assembly. While our standard production follows DIN ISO 3302-1 Class E2 (Solid) and E3 (Sponge), we are capable of achieving tighter tolerances (Class E1) for critical automotive applications upon request.
Solid Rubber Profiles – Tolerances based on DIN ISO 3302-1 Class E2
| Nominal range in mm | +/- mm | ||
|---|---|---|---|
| ≤ | 1.5 | 0.25 | |
| 1.5 | to | 2.5 | 0.35 |
| 2.5 | to | 4 | 0.4 |
| 4 | to | 6.3 | 0.5 |
| 6.3 | to | 10 | 0.7 |
| 10 | to | 16 | 0.8 |
| 16 | to | 25 | 1 |
| 25 | to | 40 | 1.3 |
| 40 | to | 63 | 1.6 |
| 63 | to | 100 | 2 |
Sponge Rubber Profiles – Tolerances based on DIN ISO 3302-1 Class E3
| Nominal range in mm | +/- mm | ||
|---|---|---|---|
| ≤ | 1.5 | 0.4 | |
| 1.5 | to | 2.5 | 0.5 |
| 2.5 | to | 4 | 0.7 |
| 4 | to | 6.3 | 0.8 |
| 6.3 | to | 10 | 1 |
| 10 | to | 16 | 1.3 |
| 16 | to | 25 | 1.6 |
| 25 | to | 40 | 2 |
| 40 | to | 63 | 2.5 |
| 63 | to | 100 | 3.2 |
Sponge Rubber Profiles – Tolerances based on DIN ISO 3302-1 Class E3
| Nominal range in mm | +/- mm | ||
|---|---|---|---|
| ≤ | 6.3 | 0.5 | |
| 6 | to | 10 | 0.7 |
| 10 | to | 16 | 0.8 |
| 16 | to | 25 | 1 |
| 25 | to | 40 | 1.3 |
| 40 | to | 63 | 1.6 |
| 63 | to | 100 | 2.0 |
| 100 | to | 160 | 2.5 |
| 160 | to | 63 | 1.5% |
Cut Length Tolerances – Based on DIN ISO 3302-1 Class L3
| Nominal range in mm | +/- mm | ||
|---|---|---|---|
| ≤ | 40 | 1.6 | |
| 40 | to | 63 | 2 |
| 63 | to | 100 | 2.5 |
| 100 | to | 160 | 3.2 |
| 160 | to | 250 | 4 |
| 250 | to | 400 | 5 |
| 400 | to | 630 | 6.3 |
| 630 | to | 1000 | 10 |
| 1000 | to | 1600 | 12.5 |
| 1600 | to | 2500 | 16 |
| 2500 | to | 4000 | 20 |
| 4000 | to | 0.005 | |
Cut Length Tolerances – Based on DIN ISO 3302-1 Class L3
| Nominal range in mm | +/- mm | ||
|---|---|---|---|
| ≤ | 3 | 0.4 | |
| 3 | to | 6 | 0.6 |
| 6 | to | 10 | 0.7 |
| 10 | to | 18 | 0.8 |
| 18 | to | 30 | 1 |
| 30 | to | 50 | 1.2 |
| 50 | to | 80 | 1.5 |
| 80 | to | 120 | 1.9 |
| 120 | to | 180 | 2.3 |
| 180 | to | 250 | 2.8 |
| 250 | to | 320 | 3.5 |
| 320 | 1.4% | ||
Cut Length Tolerances – Based on DIN ISO 3302-1 Class L3
| Nominal range in mm | +/- mm | ||
|---|---|---|---|
| ≤ | 400 | 5 | |
| 400 | to | 1000 | 10 |
| 1000 | to | 2500 | 20 |
| 2500 | to | 6000 | 30 |
| 6000 | to | 2% | |