English
Spiral wound gaskets are critical sealing components engineered for high-performance applications in demanding industrial environments. They are constructed by winding a pre-formed metal strip and a soft filler material, typically graphite or PTFE, in a V-shaped spiral around a solid metal core. This unique combination creates a robust, pressure-responsive seal that combines the resilience of the filler with the strength and spring-like recovery of the metal. Spiral wound gaskets are the preferred choice for sealing flanged connections in piping systems, pressure vessels, heat exchangers, and valves across industries such as oil & gas, chemical processing, power generation, and petrochemicals.
At Kaxite Seals, we manufacture premium spiral wound gaskets designed to meet the most stringent international standards and customer-specific requirements, ensuring leak-free operation and long-term reliability.
Selecting the correct spiral wound gasket requires careful consideration of its construction parameters. Below are the detailed specifications for Kaxite Seals products.
Kaxite Seals spiral wound gaskets are available in a complete range of sizes corresponding to flange dimensions (Nominal Pipe Size - NPS) and pressure classes (e.g., 150#, 300#, 600#, 900#, 1500#, 2500# as per ASME B16.5).
The performance is dictated by the combination of the metal winding strip and the filler material. Common standard combinations include:
| Metal Winding Material | Filler Material | Temperature Range (Approx.) | Typical Applications |
|---|---|---|---|
| 304/304L Stainless Steel | Flexible Graphite | -240°C to 550°C (in air) | General purpose, steam, hot oil |
| 316/316L Stainless Steel | PTFE | -260°C to 260°C | Aggressive chemicals, acids, high purity |
| 321 Stainless Steel | Flexible Graphite | -240°C to 650°C | High-temperature services |
| Alloy 20 | PTFE or Graphite | Depends on filler | Sulfuric acid, chemical processing |
| Monel 400 | Flexible Graphite | -240°C to 550°C | Hydrofluoric acid, marine, caustic | Titanium | Flexible Graphite | -240°C to 550°C | Chlorides, oxidizing environments |
Note: Kaxite Seals can provide gaskets with other exotic metals like Inconel, Hastelloy, and Copper, as well as specialized fillers like ceramic, mica, or non-asbestos materials.
Kaxite Seals manufactures gaskets in three primary constructions to suit different flange and application needs:
| Parameter | Specification / Capability |
|---|---|
| Design Standards | ASME B16.20, API 601, DIN EN 1514-2, ISO 7483, JIS B 2404, Custom Designs |
| Size Range (NPS) | 1/2" to 120" (Standard), Larger sizes available upon request |
| Pressure Class | 150, 300, 400, 600, 900, 1500, 2500, and Special Classes |
| Metal Thickness (Gauge) | Standard: 0.0055" to 0.007" (Custom gauges available) |
| Filler Thickness | Optimized for density and sealability based on metal gauge | Density of Wound Body | High, controlled density for uniform compression and sealing |
| Identification Tags | Standard per ASME B16.20 (Metal tag attached to outer ring) |
| Quality Certifications | ISO 9001:2015, Material Traceability, Certified Mill Test Reports |
What is the primary function of a spiral wound gasket?
The primary function is to create a reliable, leak-tight seal between two flange faces in a piping or vessel connection. It fills microscopic imperfections on the flange surfaces and contains the internal fluid or gas under varying conditions of pressure, temperature, and mechanical stress.
How do I select the right material combination for my application?
Material selection depends on three main factors: the chemical compatibility of the process media with both the metal and filler, the operating temperature range, and the pressure. Always consult the chemical resistance charts for the filler (graphite, PTFE) and the corrosion resistance tables for the metal alloy. Kaxite Seals technical team can provide expert assistance in material selection.
What is the purpose of the inner and outer rings on a spiral wound gasket?
The outer ring (centering ring) ensures the gasket is perfectly aligned within the bolt circle, prevents over-compression by acting as a compression stop, and makes handling easier. The inner ring prevents the spiral wound coil from buckling inward under pressure, protects the winding from erosion by high-velocity or turbulent flow, and can also act as a compression stop and a thermal barrier.
Can spiral wound gaskets be reused?
No, spiral wound gaskets are generally designed for single use. During bolt-up, the gasket is compressed, and the filler material flows to conform to the flange faces. Reusing a compressed gasket can lead to insufficient seating stress and potential leakage. Kaxite Seals always recommends installing a new gasket during any flange disassembly.
What is the proper bolting procedure for a spiral wound gasket?
Proper bolting is critical. Use a cross-pattern tightening sequence (star pattern) to apply preload evenly in multiple stages (e.g., 30%, 60%, 100% of final torque). Always refer to the flange manufacturer's or plant's specific bolt torque specifications, which consider factors like bolt material, lubrication, and gasket type. Under-torquing can cause leaks, while over-torquing can crush the gasket or damage flanges.
What are the signs of a failed spiral wound gasket?
Visible leakage is the most obvious sign. Other indicators can include corrosion on the flange faces adjacent to the gasket location, extrusion of the filler material, or a flattened, over-compressed appearance if the gasket is inspected after removal. Failure can result from incorrect material selection, improper installation, flawed flange faces, or conditions beyond design limits.
How does Kaxite Seals ensure the quality of its spiral wound gaskets?
Kaxite Seals implements a rigorous quality management system certified to ISO 9001:2015. We use certified raw materials with full traceability. Our manufacturing process involves precise, computer-controlled winding machinery to ensure consistent density and dimension. Every gasket undergoes dimensional inspection, and sample testing is performed regularly. Material Certifications (MTCs) are supplied with each shipment.
Can you supply spiral wound gaskets for non-standard flanges or special conditions?
Yes, customization is a core strength of Kaxite Seals. We routinely engineer and produce gaskets for non-standard sizes, unusual pressure-temperature profiles, special metallurgies, and applications requiring unique features such as jacketed constructions, kammprofile combinations, or specific regulatory compliances. Provide us with your flange drawings and service conditions for a quote.
