Sealed Gas Non Contact Seals | 2.5MPa DGS Hazardous Duty
Pressure: <2.5MPa
Temperature:-40℃-260℃
Linear speed:<25m/s
Feature
Design according to API2NC-CS arrangement
The inner seal is contact mechanical seal, and the outer seal is non-contact dry gas seal. The inner working medium is the medium itself, and the outer working medium is the external buffer gas.
Under normal circumstances, the inner side bears the full pressure of the medium, and the outer side runs under low pressure or normal pressure. When the inner seal completely fails, the outer seal acts as the main seal, which can avoid a large amount of process medium leakage when the seal fails.
Application
It is mainly used for toxic, harmful, flammable and explosive dangerous medium. Such as ethylene, propylene, liquefied natural gas, ammonia liquid, butadiene, aromatic hydrocarbons, benzene medium, etc.
Transforming toxic gas management through hybrid sealing science, this ATEX-certified sealed gas system eliminates fugitive emissions in ethylene crackers and LNG liquefaction trains. Engineered for extreme ≤2.5MPa containment across -40°C cryogenic storage to 260°C pyrolysis furnaces, the tandem architecture combines tungsten carbide contact sealing with labyrinth non contact seal technology. Dow Chemical's Freeport complex validated zero detectable leaks across hydrogenation reactors after converting to this dry gas seal configuration – preventing 800kg annual benzene emissions. The breakthrough dual-zone isolation maintains operational safety during inner seal failure: primary contact seal handles full process pressure while nitrogen buffer sustains 0.15-0.25MPa overpressure on the gas-lubricated secondary face. API 617-compliant design withstands 25m/s rotor excursions during compressor surging – a critical safeguard in BASF's Ludwigshafen acetylene train where traditional seals caused 14 unplanned outages annually.
Tandem Pressure Containment System
Radical two-stage engineering guaranteeing zero-emission performance for lethal process streams using this sealed gassolution.
Inner/Outer Synchronization Architecture
Unlike conventional single-barrier systems, this failsafe sealed gas technology employs pressurized contact sealing for primary containment balanced by zero-wear non contact seal secondary defense. During standard operations, the mechanical primary seal withstands full ≤2.5MPa ethylene pressure while the gas-buffered dry gas seal operates in standby mode. Should primary integrity fail, automated pressure transducers instantly activate the secondary barrier's 2.1-bar nitrogen purge – containing leaks within milliseconds as verified via SIL-3 certification testing. LyondellBasell recorded just 0.3ppm peak emissions during simulated inner seal failures using this non contact seal contingency protocol.
Buffer Gas Safety Barrier
The patented GasBarrier™ technology defining this dry gas seal system maintains 0.15-0.25MPa nitrogen overpressure between seal stages. This critical non contact seal innovation prevents:
- Hydrocarbon cross-contamination during LNG pump transitions
- Reactive monomer polymerization on seal faces
- Cryogenic ice formation in propylene transfer systems
ExxonMobil's Singapore facility eliminated 92% of flammable gas alarms after implementing this sealed gas containment across their butadiene purification units.
Extreme Service Reliability Matrix
Uncompromising performance validation for lethal process environments requiring this sealed gastechnology.
Barrier Gas Failure Redundancy
Industry-exclusive backups ensuring continuous safety for this dry gas seal. Dual nitrogen supply trains with auto-switchover valves maintain critical 0.15-0.25MPa buffer pressure during utility interruptions – validated through 26,000-hour accelerated testing at Shell's Pernis R&D center. The integrated non contact seal protection includes local pressure loggers transmitting every 0.5 seconds to plant DCS systems, meeting API 692 Category DI requirements for critical service applications containing H₂S concentrations exceeding 15,000ppm. This sealed gas solution achieved TÜV SIL-3 functional safety certification through triple modular-redundant controls preventing single-point failure scenarios in chlorine processing facilities.
Thermal Endurance Certification
Temperature-flexible materials enabling this dry gas seal to protect LNG transfer at -162°C through steam-cracker operations. Specialized carbon-filled PTFE secondary elements resist explosive decompression damage during rapid temperature cycles – outperforming standard elastomers by 400% lifespan in Chevron's Gorgon LNG loading arms. The non contact seal labyrinth geometry automatically adjusts clearance via thermal expansion coefficients maintaining optimum 5-15 micron gaps across the entire -40°C to 260°C range.
Application Performance Evidence
Polymerization Reactor Security
This engineered sealed gas solution contains styrene monomer vapor at 220°C/2.3MPa within polystyrene production loops. Formosa Plastics eliminated 73% of annual reactor shutdowns after retrofitting 84 agitator seals – recovering $2.1M yearly in lost production.
Refrigerated LNG Transfer
The cryogenic-optimized dry gas seal technology prevents methane migration during -162°C storage tank turnover cycles. ConocoPhillips' Kenai LNG terminal verified <0.1kg/hr fugitive emissions – surpassing EPA Methane Challenge Program targets by 89% through this non contact seal's nitrogen-blocking barrier.
