Standard gaskets don’t always fit large, irregular, or custom-designed equipment. So how do we seal those non-standard applications? That’s where spliced rubber gaskets come in.
A spliced rubber gasket is a sealing gasket made by cutting lengths of extruded rubber material and then joining (or splicing) the ends together to form a continuous, closed-loop gasket. This process is used when standard molded gaskets are not available or practical, allowing for custom sizes and shapes to be produced from rubber coils or strips.
At Julong Rubber, we often create these gaskets for large HVAC dampers, filter tanks, or enclosures that don’t match standard dimensions. It’s a flexible, fast, and cost-effective solution when molded parts aren’t available.
Why do we use spliced rubber gaskets?
Not all applications can be sealed with ready-made gaskets from a catalog.
Splicing is used when you need non-standard gasket sizes, have low production volumes, or only have access to extruded rubber profiles.
I’ve handled many requests for 1.2-meter, 2-meter, or even irregular oval-shaped gaskets that simply can’t be molded without a costly custom tool. Splicing solves that instantly—with no mold cost and very short lead time.
✅ Reasons to Use Spliced Gaskets
| Purpose | Explanation |
|---|---|
| Custom Sizes1 | Any diameter or length can be made from cord or profile |
| Material Access | Some rubber types are only available in extruded form |
| Cost-Effective2 | Avoids tooling costs for small batches |
| Fast Prototyping3 | Can be made and shipped within a few days |
✅ When customers need one gasket for a test prototype or urgent replacement, I usually recommend a spliced solution—it saves both time and tooling budget.
What are the methods for splicing rubber gaskets?
The bond is the most important part—it must be strong, airtight, and reliable.
There are three main methods for splicing: cold bonding, vulcanization, and hot splicing. Each has its own strength, speed, and cost.
In our production, we choose the method based on the application, rubber type, and performance requirement.
🛠️ Splicing Techniques Comparison
| Method | Description | Pros | Cons |
|---|---|---|---|
| Vulcanization4 | Uses uncured rubber, heat, and pressure to form a molecular bond | Strongest, permanent | Requires heat press |
| Cold Bonding5 | Uses adhesive to bond cut ends of rubber at room temperature | Fast, low-cost, no equipment | Less durable, lower strength |
| Hot Splicing6 | Uses heat and pressure, often with IR or PE film, to melt and join surfaces | Strong, smooth finish | Needs precision equipment |
✅ For low-pressure gaskets, we often use cold bonding. But for food-grade or dynamic sealing applications, we go with hot vulcanized splicing to ensure reliability.
What should be considered when designing a spliced gasket?
Not all rubber or splice shapes work the same. Small details make a big difference.
Key design considerations include the shape of the joint cut, the bond system, and material compatibility to ensure long-term sealing performance.
In my experience, even a 1mm error in cut angle7 can cause a joint to peel open after just a few pressure cycles. That’s why we train our team to cut, clean, align, and press with consistency.
✅ Key Design Considerations
| Factor | Importance |
|---|---|
| Splice Configuration | Butt-cut, beveled, or stepped joints affect strength |
| Bond System | Must match material: EPDM needs different glue than NBR |
| Surface Preparation8 | Must be clean, dry, and free from dust or oil |
| Compression Force9 | Required to hold the seal in place during curing and use |
✅ For EPDM gaskets used in outdoor dampers, we use beveled cuts and vulcanized adhesive for a seamless join that handles rain, UV, and vibration without failure.
What types of rubber can be spliced?
Most flexible elastomers can be spliced—some easier than others.
Rubber materials commonly used for spliced gaskets include EPDM, NBR, silicone, FKM, and neoprene. The selected rubber must support bonding without compromising seal integrity.
Some materials like silicone or FKM require special adhesives or heating methods. EPDM is the easiest to splice, and it’s our most popular choice for HVAC and outdoor applications.
🛠️ Spliced Rubber Material Options
| Material | Benefits | Ideal Use Cases |
|---|---|---|
| EPDM10 | UV, ozone, steam resistant | HVAC ducts, outdoor panels |
| NBR | Oil and fuel resistant | Machinery, engine covers |
| Silicone11 | Extreme temperature, food-safe | Medical, food-grade tanks |
| FKM (Viton)12 | Chemical and heat resistance | Industrial chemical containment |
| Neoprene | Moderate oil resistance and flexibility | Marine hatches, industrial covers |
✅ We keep multiple profiles in EPDM and silicone in stock to meet fast turnaround for urgent gasket needs.
What are the pros and cons of spliced rubber gaskets?
Splicing isn’t perfect, but it’s often the best choice for non-standard sealing needs.
Spliced rubber gaskets are fast and flexible, but the joint must be properly bonded to avoid failure. They are not recommended for high-pressure or dynamic sealing unless vulcanized.
When quality control is strict and the operator is experienced, a spliced gasket13 can deliver near-molded performance—without the high cost.
✅ Pros and Cons Summary
| Pros | Cons |
|---|---|
| No tooling cost | Splice may be weaker than molded part |
| Fast production, low MOQ | Not ideal for high-pressure dynamic use |
| Fully customizable in size and shape | Appearance may vary at splice joint |
| Wide range of rubber types available | Requires proper bonding and curing |
✅ For static sealing under compression—like ducts, tanks, and hatch covers—spliced gaskets give excellent results with fast delivery and no tooling investment.
Conclusion
Spliced rubber gaskets offer a smart, adaptable solution for custom-sized or irregular sealing needs. With the right method and materials, they can provide long-lasting performance in a wide range of industrial applications.
Need custom-size rubber gaskets without mold cost?
Contact Julong Rubber or Request a Quote to explore our EPDM, silicone, and Viton spliced sealing options.
Or message us directly on WhatsApp:
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Exploring this resource will provide insights into how custom sizes can enhance gasket performance and fit. ↩
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This link will explain the financial advantages of using spliced gaskets, especially for small production runs. ↩
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Discover how fast prototyping can accelerate product development and reduce time to market for gaskets. ↩
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Explore this link to understand the vulcanization process and its significance in creating strong, durable rubber products. ↩
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Learn about cold bonding techniques and their benefits for quick and cost-effective rubber repairs. ↩
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Discover the hot splicing method and its advantages for achieving strong, smooth rubber joints. ↩
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Understanding the significance of cut angle can enhance your knowledge of joint integrity and manufacturing precision. ↩
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Exploring this topic will provide insights into best practices for ensuring strong adhesive bonds and preventing failures. ↩
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Learning about compression force will help you understand its role in maintaining effective seals and preventing leaks. ↩
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Explore this link to understand why EPDM is the top choice for HVAC and outdoor applications, ensuring durability and efficiency. ↩
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Discover the unique properties of silicone that make it ideal for medical and food-grade uses, ensuring safety and performance. ↩
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Learn how FKM (Viton) is utilized in various industries for its chemical and heat resistance, enhancing safety and reliability. ↩
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Explore the advantages of spliced gaskets, including cost-effectiveness and performance, to enhance your sealing solutions. ↩
