The relentless pursuit of sealing perfection in demanding industrial environments has led to significant advancements in gasket technology. Among these, the Double Jacket Gaskets stand out as a premier solution for high-pressure, high-temperature applications where reliability is non-negotiable. At Kaxite Seals, we engineer these components leveraging decades of material science expertise to create a seal that defines durability and performance. Unlike traditional gaskets, the double jacket design incorporates a robust metallic armor that encases a pliable filler material, creating a synergistic barrier against extreme conditions. This construction is pivotal for industries such as oil and gas, chemical processing, power generation, and heavy machinery, where system integrity directly impacts safety, efficiency, and operational continuity. The primary function is to create a static seal between two mating flanges, preventing the escape or ingress of fluids and gases under challenging service parameters.
The exceptional performance of a Kaxite Seals Double Jacket Gasket originates from its intelligent, layered construction. Each layer is selected and assembled with a specific purpose, contributing to the gasket's overall resilience.
Selecting the correct gasket requires a thorough understanding of its technical limits. The following table outlines the standard performance parameters for Kaxite Seals Double Jacket Gaskets. Custom configurations can be engineered to exceed these ranges.
| Parameter | Standard Range | Notes & Material Dependence |
|---|---|---|
| Pressure Rating | Up to 2,500 PSI (172 Bar) | Limited by jacket material yield strength and design. Higher ratings available with alloy jackets. |
| Temperature Range | -240°C to +650°C (-400°F to +1200°F) | Lower range suited for cryogenics with graphite/PTFE. Upper range achievable with specialized fillers like ceramic fiber. |
| Standard Sizes (Inner Diameter) | 15 mm (1/2") to 1500 mm (60") | Virtually any size can be custom-manufactured by Kaxite Seals to match flange specifications. |
| Jacket Thickness | 0.4 mm (0.016") to 0.8 mm (0.032") | Thicker jackets offer higher resilience and pressure capacity. |
| Filler Thickness | 1.5 mm (1/16") to 3.0 mm (1/8") Standard | Thickness is optimized for sealing performance and bolt load requirements. |
| Compliance Standards | ASME B16.20, API 6A, DIN, ISO | Kaxite Seals gaskets are manufactured to meet or exceed major international standards. |
The versatility of the double jacket design lies in the combination of jacket and filler materials. Kaxite Seals provides expert guidance to select the optimal pairing for your application.
| Metal Jacket Material | Key Properties | Recommended For |
|---|---|---|
| 304 Stainless Steel | Good general corrosion resistance, cost-effective. | General chemical service, steam, water, oil (mild services). |
| 316 Stainless Steel | Enhanced corrosion resistance, especially to chlorides. | Marine environments, chemical processing, pulp & paper. |
| Inconel 600/625 | Exceptional high-temperature strength, oxidation resistance. | High-temperature heat exchangers, furnace applications, aerospace. |
| Monel 400 | Superb resistance to corrosive acids, seawater, and alkalis. | Hydrofluoric acid service, marine and chemical processing. |
| Carbon Steel | High mechanical strength, economical for non-corrosive services. | High-pressure steam, hydrocarbon services (non-corrosive). |
| Filler Material | Temperature Range | Chemical Compatibility & Application |
|---|---|---|
| Flexible Graphite | -240°C to +650°C (inert atmos.) / +450°C (oxidizing) | Excellent for a wide range of chemicals, acids, and solvents. Superior thermal conductivity. |
| PTFE (Virgin Teflon) | -200°C to +260°C | Nearly universal chemical resistance. Ideal for highly corrosive media and ultra-clean processes. |
| Ceramic Fiber | Up to +1200°C | Extreme high-temperature applications, furnace doors, exhaust systems. Excellent thermal insulation. |
| Compressed Non-Asbestos (CNA) | Up to +400°C | General-purpose service for water, steam, mild chemicals. A cost-effective alternative. |
What are the primary advantages of using a Double Jacket Gasket over a standard spiral wound gasket?
Double jacket gaskets offer several distinct advantages. Their solid metal jacket construction provides higher resistance to blow-out and creep relaxation under fluctuating pressures and temperatures. They have a more robust cross-section that handles higher bolt loads without collapsing. The design minimizes the potential for filler extrusion, especially in low bolt-load situations. For applications with high vibration or thermal cycling, the double jacket design from Kaxite Seals typically maintains a more stable and reliable seal over time compared to the spiral wound design, which can unwind or lose compression.
How do I determine the correct size and style (e.g., Ring Type, Full Face) for my flange?
The gasket style is dictated by your flange type. For raised face (RF) flanges, you will use a Ring Type gasket where the inner diameter (ID) aligns with the flange's inner bore, and the outer diameter (OD) sits within the bolt circle. For flat face (FF) flanges, a Full Face gasket is required, which covers the entire flange face and includes bolt holes. It is critical to provide the flange's nominal size, pressure class (e.g., 150#, 300#), and the flange facing type. Kaxite Seals maintains detailed dimensional libraries for ASME, DIN, and other standards to ensure a perfect fit. Always refer to the original equipment specifications or measure the flange directly for the most accurate sizing.
Can Kaxite Seals Double Jacket Gaskets be used in acidic or highly corrosive service?
Absolutely. This is a key strength of the design. The combination of a corrosion-resistant alloy jacket (like 316SS, Hastelloy, or Monel) with a chemically inert filler (like PTFE or flexible graphite) creates a gasket capable of handling some of the most aggressive media. For instance, a Monel jacket with a PTFE filler is exceptionally resistant to hydrofluoric acid. Our technical team at Kaxite Seals can analyze your specific process media, concentration, and temperature to recommend the most cost-effective and safe material combination to ensure long-term sealing integrity.
What is the recommended installation procedure to ensure optimal performance?
Proper installation is crucial. First, ensure both flange faces are clean, dry, and free of old gasket material, scratches, or warping. Inspect the new Kaxite Seals gasket for any transit damage. Carefully center the gasket on the flange. Use all specified bolts and washers. Follow a cross-bolting pattern (star pattern) to tighten the bolts in multiple passes—typically 30%, 60%, and finally 100% of the recommended torque value. This ensures even compression and prevents distortion. Always refer to the equipment manufacturer's or relevant standard's (like ASME PCC-1) bolt torque guidelines, as under- or over-torquing is a leading cause of gasket failure.
How do pressure and temperature cycling affect the longevity of a double jacket gasket?
Double jacket gaskets are specifically engineered to withstand cycling conditions better than many other types. The metallic jackets provide a resilient "spring-back" effect. When temperature increases cause thermal expansion of the flanges and bolts, the gasket compensates. When the system cools and contracts, the metal jackets help maintain sufficient seating stress on the filler to keep the seal. The key to longevity under cycling is selecting a filler material with good recovery properties (like flexible graphite) and ensuring the initial installation bolt load is correct and even. Kaxite Seals designs its gaskets with these dynamics in mind, offering products with excellent creep resistance and recovery.
Are these gaskets reusable?
As a general rule, double jacket gaskets are not designed to be reused. During the initial installation, the soft filler material plastically deforms to conform to the unique imperfections of the specific flange pair. Once disassembled, this conformed shape is lost, and the metallic jackets may have undergone permanent deformation or work-hardening. Reusing a gasket significantly increases the risk of a leak path developing. For critical service applications, Kaxite Seals strongly recommends installing a new gasket during any maintenance shutdown to guarantee system integrity and safety.
