Spiral wound gaskets are a cornerstone of industrial sealing technology, renowned for their exceptional reliability in demanding applications. Essentially, they are engineered sealing elements created by winding a pre-formed metal strip (the "windings") and a soft filler material (such as graphite, PTFE, or ceramic) in a precise, alternating spiral pattern around a solid metal inner ring. This unique construction combines the spring-like resilience of the metal with the conformable sealing properties of the filler. The outer edge is typically secured with an optional outer metal ring, which provides radial stability, aids in centering the gasket within the flange, and helps prevent over-compression. These gaskets are specifically designed for use in raised face (RF) and male-and-female (M&F) flanges, creating a robust seal that can withstand high temperatures, extreme pressures, and challenging chemical environments.
At Kaxite Sealing, we leverage decades of manufacturing expertise to produce spiral wound gaskets that set the industry standard for performance and longevity. Our gaskets are not just components; they are engineered solutions for critical sealing challenges.
Choosing the correct spiral wound gasket is paramount for safety and system integrity. The selection depends on three primary factors: the flange standards, the operating media (chemical, temperature, pressure), and the required performance characteristics. Below are detailed specifications for standard Kaxite Sealing products.
Kaxite Sealing manufactures spiral wound gaskets to all major international standards, ensuring perfect fit and function.
The table below outlines common metal winding and filler material combinations offered by Kaxite Sealing, along with their key properties and typical applications.
| Metal Winding Material | Filler Material | Temperature Range (Approx.) | pH Range | Key Features & Typical Applications |
|---|---|---|---|---|
| 304 Stainless Steel | Flexible Graphite (GRA) | -200°C to 550°C (Inert/Reducing) / 450°C (Oxidizing) | 0-14 | Excellent general-purpose combination. Good thermal conductivity, high temperature resistance. Used in steam, hydrocarbons, and many chemical services. |
| 316L Stainless Steel | PTFE | -200°C to 260°C | 0-14 | Superior corrosion resistance. Ideal for highly corrosive acids, alkalis, and solvents where temperature permits. |
| Inconel 625 | Flexible Graphite (GRA) | -200°C to 980°C | 0-14 | Exceptional high-temperature strength and oxidation/corrosion resistance. For high-temperature heat exchangers, reformer furnaces, and aerospace. |
| Titanium | Flexible Graphite (GRA) | -200°C to 550°C | Varies | Excellent for chloride-containing environments and specific corrosive media like wet chlorine and nitric acid. |
| Monel 400 | Ceramic/Mica | Up to 1000°C | N/A | Used in high-temperature, high-pressure steam services and applications involving hydrofluoric acid. |
For easy identification and to prevent installation errors, Kaxite Sealing spiral wound gaskets often follow a visual color-coding system on the outer ring (where applicable):
Q: When should I use a spiral wound gasket instead of a flat gasket or a ring joint?
A: Spiral wound gaskets are the preferred choice for a wide range of medium to high-pressure/temperature applications involving raised face flanges, especially where thermal cycling or vibration is present. Use them over basic flat gaskets when sealing performance, reliability, and safety are critical. They are generally used where ring joint gaskets (RJTs) are not specified; RJTs are typically for higher-pressure, smaller-bore applications with ring-type joint (RTJ) flanges. The spiral wound gasket's resilience makes it superior to static seals in dynamic operating conditions.
Q: How do I select the right metal and filler material for my application?
A: Selection is a three-step process. First, identify the flange standards and dimensions. Second, and most critically, analyze the operating conditions: the chemical composition of the media, the continuous and peak temperatures, and the system pressure. Third, consider external factors like thermal cycling frequency. For example, for high-temperature steam, a 304SS/Graphite gasket is common. For concentrated sulfuric acid at moderate temperatures, a 316L/PTFE combination would be selected. Kaxite Sealing's engineering team can provide detailed material selection guidance based on your specific process parameters.
Q: What is the purpose of the inner and outer rings on a spiral wound gasket?
A: The solid metal inner ring serves multiple vital functions. Primarily, it acts as a compression stop during bolt-up, preventing the soft spiral wound filler from being over-compressed and extruding into the pipeline bore, which could cause blockage or contamination. It also provides radial strength and helps center the gasket. The optional outer ring provides additional radial stability, helps in handling and centering the gasket, and most importantly, significantly increases the gasket's resistance to blowout under high internal pressure by containing the windings.
Q: How do I properly install and torque a spiral wound gasket?
A: Correct installation is key to achieving a leak-free seal. Ensure the flange faces are clean, undamaged, and aligned. Place the gasket concentrically on the flange. The inner ring should be flush with or slightly inside the bore. Always use a cross-bolt tightening pattern (star pattern) in multiple stages to apply load evenly. Follow the recommended bolt torque values specified by the flange standard (e.g., ASME PCC-1) or the equipment manufacturer, using calibrated torque wrenches. Under-torquing can cause leaks; over-torquing can crush the gasket's windings, destroying its resilience and sealing capability.
Q: Can spiral wound gaskets be reused?
A: It is strongly discouraged to reuse spiral wound gaskets. Once compressed during installation, the winding and filler materials undergo permanent deformation and take a "set" specific to that flange assembly. Reusing a gasket in the same or a different flange will not provide the same controlled spring-back and sealing force, greatly increasing the risk of a leak. For safety, reliability, and cost-effectiveness, always use a new Kaxite Sealing spiral wound gasket during any flange reassembly.
Q: What certifications do Kaxite Sealing spiral wound gaskets carry?
A: Kaxite Sealing is committed to the highest quality standards. Our manufacturing facilities and products can be supplied with various certifications upon request, including but not limited to ISO 9001:2015 for quality management, API 6A for wellhead and Christmas tree equipment, and CE marking for relevant products. We also provide full material traceability with Mill Test Certificates (MTCs/CMPs) for all metallic components.
The versatility and robustness of spiral wound gaskets make them indispensable across countless industries. Kaxite Sealing provides solutions tailored to each sector's unique demands.
