Introduction to Spiral Wound Gaskets
What is a Spiral Wound Gasket?
A spiral wound gasket is a type of sealing device used between two flanges to prevent leaks from high-pressure or high-temperature systems. It’s crafted using alternating layers of metal (usually stainless steel) and a filler material like graphite or PTFE. This makes it strong, flexible, and incredibly reliable.
Why They’re Preferred in Industrial Applications
Unlike traditional gaskets, metal wound gaskets combine the best of both worlds—metal’s strength and the sealant flexibility of soft filler. They’re the go-to option when dealing with extreme environments such as chemical plants, refineries, or offshore rigs.
Where They Are Used
You’ll find spiral-seal gaskets in:
- Heat exchangers
- Steam pipelines
- Reactor vessels
- Flange joints in chemical plants
- High-temperature gas pipelines
Key Components of spiral-seal gaskets
Metal Winding Strip
This is the core strength of the gasket, usually made from stainless steel like SS316 or SS304. It provides structural integrity.
Filler Material
Soft materials like graphite, PTFE, or mica are layered with the metal strip to ensure a tight, leak-proof seal even under vibration or temperature shifts.
Outer and Inner Rings
These rings help in centering the gasket and prevent blowout. Inner rings also protect against erosion.
Types of Spiral Wound Gaskets
With Inner Ring
Great for preventing inward buckling. Ideal for high-pressure systems.
With Outer Ring
Helps center the gasket during installation and supports compression.
With Inner & Outer Rings
Best for critical environments—gives full structural and sealing performance.
Flange spiral-seal gaskets
Custom-made to fit ANSI or DIN flanges, often used in oil & gas pipelines.
Popular Materials Used in industrial gaskets
SS316 Spiral Wound Gasket
Offers excellent corrosion resistance and heat tolerance. Great for chemical plants and seawater pipelines.
SS304 Spiral Wound Gasket
Affordable, corrosion-resistant, and widely used in food and water applications.
PTFE Spiral Wound Gasket
PTFE is chemically inert—making it perfect for aggressive acids or sensitive pharmaceutical media.
Graphite Spiral Wound Gasket
Highly flexible, high-temperature capable. It handles up to 550°C and resists chemicals well.
Branded Gaskets Comparison
Flexitallic Spiral Wound Gasket
Known for durability and precision. Used globally in critical applications.
Teadit Spiral Wound Gasket
Reliable sealing under stress. Commonly used in petrochemical plants.
Garlock Spiral Wound Gasket
Premium option with custom designs and extensive chemical resistance.
Applications by Industry
Petrochemical & Refining
High-temp and pressure gaskets are essential in reactors and heat exchangers.
Oil & Gas
Handles fluctuating pressures and harsh media in upstream and downstream processes.
Power Plants
Used in boiler flanges and steam lines—especially graphite-filled types.
Marine & Offshore
SS316 spiral gaskets are perfect for seawater pipelines and offshore oil rigs.
Food & Pharma
PTFE gaskets meet hygiene standards while delivering excellent sealing.
Spiral Wound Gasket Standards & Compliance
ASME B16.20
The most widely used specification for gasket for high-pressure applications—covers sizes, materials, and tolerances.
DIN & EN Standards
Essential for European clients—Unifit complies with all.
Custom Sizes & Certifications
From ½” to 60” and beyond—we offer full MTCs, third-party inspections, and ISO certifications.
Why Choose Unifit Metalloys as Your Supplier
Custom Manufacturing
Get spiral-seal gaskets made for your specs—any shape, any standard.
Quick Turnaround
We maintain stock of popular sizes and ship globally in record time.
Global Delivery
Serving clients in 40+ countries with prompt logistics and secure packaging.
How to Select the Right Spiral Wound Gasket
Know Your Pressure and Temperature
Higher the stress, tougher the gasket should be—use graphite or SS316 for harsh environments.
Match the Filler with Media
PTFE for acids, graphite for high-temp steam, mica for extreme pressure.
Select the Right Metal
SS316 for corrosion, SS304 for economy, titanium for specialized chemical service.
Final Thoughts
A spiral wound gasket isn’t just a ring—it’s the backbone of leak-proof piping systems. Whether you’re in petrochemicals, marine, or pharma, choosing the right type and material can protect your operation from costly downtimes. At Unifit Metalloys, we don’t just sell gaskets—we help you seal your success.
FAQs
Q1: What is the most common spiral wound gasket size?
Most common sizes range between ½” to 24” for industrial pipelines.
Q2: Which filler is better—PTFE or graphite?
Graphite is best for high temperatures. PTFE is ideal for corrosive chemicals and food-grade systems.
Q3: Can Unifit supply custom spiral wound gaskets?
Yes, we specialize in custom builds with short lead times and global shipping.
Q4: What’s the best spiral wound gasket for seawater?
SS316 spiral wound with PTFE filler is perfect for seawater applications.
Q5: Are spiral wound gaskets reusable?
No. They are designed for single-use to maintain seal integrity.