The dry gas seal with a central labyrinth is a high-performance dual-end-face sealing solution specifically designed for high-speed rotary gas compressors. Its core feature is a precision structure of dual-end-face series connection + central labyrinth (as shown in the diagram with double-layer sealing rings and a central labyrinth channel). This achieves a reliable seal with zero leakage and a long service life, making it an ideal choice for high-risk gas applications in chemical, energy, and other fields.
Core Design Features:
- Dual-End-Face Series Connection + Central Labyrinth Structure：
The seal employs two sealing end faces arranged in series, connected by a labyrinth seal (as shown in the diagram with double-layer sealing rings and a central labyrinth channel), forming a triple protection system of “main seal + secondary seal + labyrinth isolation.” The main seal handles the sealing of the medium under normal operating conditions, the secondary seal provides safety redundancy, and the central labyrinth further prevents the medium from communicating with external inert gases, completely eliminating the risk of cross-contamination and leakage.
- Non-contact sealing face:
The sealing face features a precision-grooved design, forming a stable air film between the faces during operation. This achieves non-contact operation, eliminating frictional wear and heat buildup. It is compatible with ultra-high-speed shaft systems ≤180m/s, significantly extending seal life while avoiding the heat generation, deformation, and failure problems of traditional contact seals.
- Flexible groove selection:
Groove types can be selected based on operating conditions, offering unidirectional or bidirectional designs. Unidirectional grooves are suitable for equipment rotating in only one direction, providing stronger air film rigidity; bidirectional grooves support both forward and reverse rotation, meeting the complex needs of compressor start-up and shutdown, and operating condition switching, thus improving application flexibility.
- Dynamic ring outer circumference encapsulation structure:
The dynamic ring outer circumference employs a special encapsulation structure. In the event of accidental failure of the main seal, it effectively prevents debris and impurities from entering the secondary seal and labyrinth channel, reducing secondary damage and buying time for emergency shutdown and maintenance, preventing the accident from escalating.
- High-performance polymer seals:
Key seals utilize special polymer materials that are temperature-, pressure-, and corrosion-resistant. They maintain stable elasticity and sealing performance over an ultra-wide temperature range of -160℃ to 260℃ and a pressure range of 0 to 25MPa, resisting low-temperature embrittlement, high-temperature aging, and media corrosion.
- Modular assembly/disassembly design:
The overall design adopts a modular structure (as shown in the layered sealing assembly), allowing for installation, maintenance, and component replacement without disassembling the main equipment. This significantly reduces downtime, lowers maintenance costs, and adapts to equipment with different shaft diameters (25~400mm).
Key Operating Parameters:
- Operating Temperature: -160℃ ~ 260℃, covering extreme conditions such as cryogenic liquefaction and high-temperature reactions.
- Operating Pressure: 0 ~ 25MPa, suitable for medium-high pressure to ultra-high pressure gas compression scenarios.
- Linear Velocity: ≤ 180m/s, meeting the rotational requirements of high-speed compressors, turbines, and other equipment.
- Compatible Shaft Diameter: 25 ~ 400mm, customized size solutions can be provided according to the equipment’s shaft system.
Core Product Advantages：
- Dual-Stage Safety Sealing Guarantee
The main seal is the core working seal, and the secondary seal is a safety backup seal. When the main seal fails due to wear, impurities, etc., the secondary seal can operate independently and safely under the full pressure of the medium, ensuring that process gas will not leak into the atmosphere, and that external inert gases will not intrude into the unit, perfectly adapting to high-risk gas conditions requiring “zero leakage.”
- Long Lifespan and Low Maintenance
The non-contact operating mode eliminates end-face wear, while the central labyrinth and encapsulation structure further reduce the risk of failure. Combined with high-performance materials, this results in a seal lifespan far exceeding that of traditional contact seals. The modular design makes replacement of vulnerable parts easier, significantly reducing total lifespan maintenance costs.
- Wide Operating Condition Adaptability
From cryogenic LNG compression to high-temperature circulating hydrogen compression, and from atmospheric pressure to 25MPa high-pressure conditions, it maintains stable sealing performance, unaffected by drastic fluctuations in temperature, pressure, and speed, adapting to various complex industrial scenarios.
- Environmental and Safety Compliance
Completely eliminates the leakage of toxic, flammable, and explosive gases into the atmosphere, complying with environmental and safety production regulations. It also prevents external impurities from entering the equipment, ensuring product purity and stable equipment operation.
Typical Application Scenarios:
- Ammonia Compressors: Seal toxic ammonia gas to prevent leaks that could cause safety and environmental accidents.
- Natural Gas Compressors: Ensure zero-leakage long-distance natural gas transportation, improving energy transmission efficiency.
- Circulating Hydrogen Compressor: Used in hydrogen refueling and production processes to seal flammable and explosive hydrogen, ensuring production safety.
- Circulating Gas Compressor: Adaptable to various process gases in the chemical and petrochemical industries, meeting stringent sealing requirements.
Gas Flow Description:
A: Primary Sealing Gas: Sealing gas on the process medium side, used to isolate the main seal from the medium.
B: Primary Leakage Gas: Gas leaking slightly from the main seal, collected and treated.
C: Secondary Sealing Gas: Inert isolation gas, used to isolate the secondary seal from the atmosphere.
D: Secondary Leakage Gas: Gas leaking slightly from the secondary seal, collected and treated.
E: Isolation Gas: Inert gas introduced through the central labyrinth, further isolating the medium from the atmosphere.
Standards and Reliability:
Product design and manufacturing strictly adhere to international sealing industry standards and safety specifications such as API and ISO. Through pressure cycle testing, high-speed life testing, and leak detection verification, stable and reliable performance is ensured during long-term continuous operation, providing ultimate sealing protection for high-risk gas compression equipment.
