Reliable Double Jacket Gasket Solutions for Industrial Manufacturers

What are Double Jacket Gaskets?

In demanding industrial sealing applications, where extreme pressures and aggressive media are the norm, standard gasket solutions often fall short. This is where the engineered superiority of Double Jacket Gaskets comes into play. These are high-performance, metallic sealing elements specifically designed to handle severe service conditions that would compromise other gasket types. At their core, a double jacket gasket consists of a soft, compressible filler material—typically graphite, PTFE, or ceramic—enclosed within a dual-layer metal jacket. This robust construction combines the sealing resilience of the filler with the structural integrity and blowout resistance of the metal armor, creating a seal that maintains its integrity under high bolt loads, thermal cycling, and corrosive environments.

Kaxite Seals specializes in the design and manufacture of premium double jacket gaskets, leveraging decades of metallurgical and sealing expertise. Our products are the go-to choice for engineers and maintenance professionals in sectors where failure is not an option.

Key Features and Advantages of Kaxite Double Jacket Gaskets

• Exceptional Pressure Resistance: The double-layer metal jacket provides superior containment, preventing filler extrusion and seal failure even under extreme internal pressures.
• High-Temperature Stability: Capable of performing reliably across a wide temperature range, depending on the filler and metal jacket material selection.
• Excellent Corrosion & Chemical Resistance: The choice of jacket metals (like 316 Stainless Steel, Monel, Titanium) and inert fillers like PTFE offers compatibility with a vast array of corrosive fluids and gases.
• Superior Blowout Resistance: The mechanical strength of the metal jackets anchors the gasket firmly in place, resisting the shear forces that can cause other gaskets to fail catastrophically.
• Creep Relaxation Resistance: The metallic construction minimizes the tendency of the seal to relax under constant load and temperature, ensuring a lasting, leak-tight seal.
• Custom Engineering: Kaxite Seals provides custom-designed gaskets to meet non-standard sizes, pressures, or chemical exposure requirements.

Detailed Product Parameters & Specifications

Kaxite Seals manufactures double jacket gaskets to meet precise application demands. The performance is dictated by the combination of materials used for the jacket and the filler core.

Standard Metal Jacket Materials

Standard Filler Materials

Standard Size & Pressure Ratings

Kaxite Double Jacket Gaskets are manufactured to industry-standard dimensions, including ASME B16.20, API 6A, and DIN standards. Common sizes range from 1/2" NB to 48" NB. Pressure ratings are intrinsically linked to the flange class and gasket width. They are routinely specified for:

• ASME Class 150 through Class 2500 flanges
• API 6A wellhead equipment
• High-pressure pipeline and vessel connections

Note: Always consult Kaxite Seals engineering data for the specific pressure-temperature rating of your material combination and flange class.

Double Jacket Gaskets - Frequently Asked Questions (FAQ)

What is the main difference between a Single Jacket and a Double Jacket Gasket?
A single jacket gasket has a metal jacket folded over the filler material on only one side (top and bottom are the same fold). A double jacket gasket uses two separate, independent metal jackets—one for the top and one for the bottom—which are crimped or rolled together at the inner and outer diameters. The double jacket design offers significantly higher mechanical strength, better resistance to internal pressure and blowout, and is generally recommended for more severe service conditions, higher pressures, and larger diameters.

When should I choose a Double Jacket Gasket over a Spiral Wound Gasket?
Double jacket gaskets are often preferred in applications with exceptionally high internal pressure, potential for severe pressure spikes (water hammer), or where the sealing flange faces may have minor imperfections. The solid metal jacket provides a more rigid, non-flexing sealing element that resists over-compression and filler extrusion better than the spirally wound metal of a spiral wound gasket. Spiral wound gaskets excel in thermal cycling and are often more economical for standard high-pressure services.

How do I select the right metal and filler material for my application?
Material selection is a critical three-step process: 1) Chemical Compatibility: The filler must be inert to the process media, and the metal jacket must resist corrosion from both the internal fluid and the external environment. 2) Temperature: Both materials must withstand the maximum and minimum continuous operating temperatures and any thermal shock. 3) Pressure: The metal jacket must have sufficient yield strength to resist deformation at your operating and bolt loads. The team at Kaxite Seals provides free technical support to help you navigate this selection.

Can Double Jacket Gaskets be used in heat exchangers and pressure vessels?
Yes, they are an excellent choice for both. In heat exchangers (shell-and-tube, plate), they provide reliable sealing on channel covers, bonnets, and divider plates, handling the thermal stresses between different media. For pressure vessel manways and nozzle connections, their high blowout resistance is a key safety feature. It is crucial to ensure the gasket dimensions match the specific flange design of your equipment.

What flange surface finish is recommended for installing a Double Jacket Gasket?
A smooth, flat finish is ideal. A serrated finish (like concentric or phonographic grooves with a 125-250 µin Ra finish) is commonly specified. This finish provides excellent "bite" for the metal jacket, creating a strong mechanical seal and preventing gasket movement. Mirror-finish surfaces are not recommended as they can lead to slippage. Always follow the original equipment manufacturer's or applicable standard's (like ASME PCC-1) recommendation for surface finish.

How important is bolt load and tightening procedure for these gaskets?
Extremely important. Double jacket gaskets require a high initial bolt load to properly compress the filler material and seat the metal jackets into the flange faces. Under-torquing is a leading cause of leakage. It is essential to use a controlled bolt tightening pattern (e.g., criss-cross pattern) and, preferably, a calibrated torque wrench or hydraulic tensioning system to achieve even, consistent load across all bolts as per guidelines like ASME PCC-1. Re-torquing after a heat cycle is often recommended.

Are Kaxite Double Jacket Gaskets reusable?
As a rule, metallic gaskets, including double jacket types, are not designed to be reusable. Once compressed during installation, the filler material undergoes plastic deformation, and the metal jackets conform to the flange faces. Reusing a gasket that has been in service risks a compromised seal due to work-hardening of the metal, loss of filler thickness, and potential embedding of previous flange surface imperfections. For reliability and safety, a new gasket should always be installed during maintenance.

Can you manufacture custom shapes and sizes?
Absolutely. While Kaxite Seals stocks a wide range of standard ring-type gaskets (R/JR style), we have extensive capabilities for custom fabrication. We can produce oval, rectangular, obround, and other special shapes to fit unique vessel openings or proprietary equipment. We can also work with special metal alloys or filler composites to meet exotic application requirements.