Engineering a New Benchmark in Compressor Protection: The Type 93AX Coaxial Separation Seal

In compressor operations, small failures can create large-scale consequences, from unplanned shutdowns to safety incidents. One weak link can be the separation seal, which is critical in protecting dry gas mechanical seals from oil contamination. Yet, conventional radial designs often struggle to perform under today's higher pressures, temperatures and operating speeds.

Raising the Bar for Separation Seal Performance

Radial separation seals have served the industry well, offering effective protection in various compressor applications. However, those same designs can face limitations as operational demands grow more challenging, with higher speeds, pressures and temperatures.

Operators are now seeking solutions that deliver:

• Greater resilience under variable and high-stress conditions
• Lower gas consumption without compromising protection
• Improved uptime and reduced maintenance intervals

In critical environments, such as offshore oil and gas platforms, midstream transport systems, such as pipelines, petrochemical plants and high-pressure power generation facilities, minor performance degradation can lead to significant reliability issues or costly downtime. These challenges have driven the development of more advanced sealing technologies designed to meet today's higher operational standards.

Meeting Real-World Needs: Why the Type 93AX Was Created

John Crane developed the Type 93AX coaxial separation seal in response to industry demands. Customers across oil and gas, power and clean energy sectors need a mechanical seal that can:

• Minimise nitrogen supply
• Maintain protection from leaks and oil contamination, during failure scenarios
• Operate reliably under high-speed, high-pressure and high-temperature conditions

The result is a robust coaxial seal with a non-contacting design that addresses the pain points of radial technologies head-on.

What Makes the Type 93AX Different?

The Type 93AX mechanical seal features an axial configuration, allowing for a consistent, high-stiffness film of nitrogen to separate the faces without wear. At the core is TriHex grooved seal face technology, which enhances barrier gas control while reducing gas consumption.

What sets it apart is its ability to operate effectively in three distinct scenarios:

• Normal Operation: Sustains a non-contacting gas barrier to stop oil ingress.
• Separation Gas Failure: Continues to operate in a non-contacting state even without an active nitrogen supply.
• Dry Gas Seal Failure: Maintains pressure resistance up to 35 bar, restricting process gas from escaping into the atmosphere.

These features enable the Type 93AX to protect compressors even during component failure, helping prevent secondary damage and unplanned outages.

Seal Design Backed by Engineering Excellence

The development of the Type 93AX separation seal was driven in engineering and research, supported by extensive testing and validation, including:

• Computational Fluid Dynamics (CFD) Simulations: Used to predict fluid dynamics and optimise seal geometry.
• Prototype Testing: Built and tested on a custom rig to measure load capacity and leakage.
• Design of Experiments: Systematic adjustment of variables such as film gap, groove geometry and pilot hole configuration to evaluate their impact and optimise overall seal performance.
• Third-Party Validation: Independent analysis confirmed CFD results and verified sealing reliability.

This process allowed John Crane to fine-tune the separation seal's performance in standard and failure scenarios, ensuring real-world readiness.

Why It Matters for Operators

The Type 93AX delivers measurable benefits across reliability, safety and cost:

• Enhanced protection for dry gas seals, even under failure conditions
• Reduced maintenance from non-contacting design and longer MTBR
• Lower nitrogen uses up to 80%, reducing energy demand and simplifying supply logistics
• Extended compressor life by mitigating seal face wear and oil contamination

For turbomachinery engineers and reliability managers, it means controlling risks and locking-down compressor performance, so you don't have to worry.

Ready to Upgrade Your Compressor Sealing Strategy?

The Type 93AX coaxial separation seal isn't just a new product; it's a new benchmark for next-generation separator seals in mission-critical compressors—engineered to reduce risk, downtime and nitrogen consumption while enhancing operational efficiency. Designed to integrate with all modern compressor designs and fully compatible with John Crane's portfolio of high-performance dry gas seals, it supports both new installations and aftermarket upgrades.

Backed by our global service network, the Type 93AX also offers rapid-response refurbishment, maintenance and repair—delivering measurable value throughout the lifecycle of your equipment. Contact our experts to learn how this separation seal can reduce risks and downtime and enhance efficiency.