Reverse-Balanced Multi-Spring Cartridge Mechanical Seal

Description; 

The SC620 is a high-performance single cartridge mechanical seal featuring a multi-spring, reverse-balance design engineered for demanding industrial services involving pressure fluctuations, elevated temperatures, and chemically aggressive media. The cartridge-mounted construction ensures precise axial setting, minimizes installation errors, and improves equipment reliability while reducing commissioning time. Its hydraulically balanced face geometry reduces face loading and heat generation, enabling stable sealing performance under variable operating conditions. 

 

Designed for process industries requiring dependable sealing performance and extended service life, the SC620 is suitable for centrifugal pumps, process pumps, industrial blowers, mixers, and auxiliary rotary equipment operating in chemical, petrochemical, pharmaceutical, power, pulp & paper, steel, mining, food processing, and solvent handling environments. The robust multi-spring arrangement provides uniform face loading and enhanced operational stability in applications involving vibration, thermal cycling, and intermittent duty conditions. 

Key Features; 

• Available in both metric and inch shaft sizes for compatibility with global industrial standards and plant‑wide standardisation. 

• Cost‑effective, refurbish-able design allowing replacement of wear components and reuse of hardware, reducing long‑term sealing costs. 

• Quick installation and easy removal of the cartridge assembly minimise downtime and simplify routine maintenance and refurbishment. 

• Single cartridge mechanical seal with factory‑assembled, preset working length for simplified installation, precise alignment and reduced setting errors. 

• Bidirectional capability, independent of shaft rotation direction, allowing flexible integration into a wide variety of pump and rotating‑equipment configurations. 

• Hydraulically balanced (reverse‑balanced) seal faces minimise face loading at higher pressures, reducing wear and extending seal service life across a broad pressure range. 

• Internal, single‑seal arrangement promotes effective lubrication, good pressure handling and improved protection of springs and dynamic components from contamination. 

• Multi‑spring / wave‑spring reverse‑balanced design providing stable, uniform face loading, improved heat dissipation and reliable performance under varying operating conditions. 

• Optional flushing and quench connections enable integration with seal support systems for enhanced cooling, solids management and environmental control where required by the service. 

• High corrosion resistance through a wide selection of metallurgy and elastomer combinations, enabling customisation to clean liquids, light slurries and moderate chemical process applications. 

 

Service Overview; 

Parameter	Value
Equipment	Centrifugal pumps, process pumps, industrial blowers, rotary machines
Fluid	Chemicals, hydrocarbons, solvents, light slurry, water, process fluids
Service Nature	Continuous industrial process duty
Operating Mode	Single cartridge, reverse-balanced multi-spring mechanical seal

 

Specifications; 

Item	Min	Max	Typical / Notes
Shaft Size	20 mm (0.750”)	300 mm (12.000”)	Metric & inch sizes available
Pressure	Vacuum	40 bar (580 psi)	Depending on seal face & metallurgy
Temperature	-40°C (-40°F)	+220°C (+428°F)	Based on elastomer selection
Speed	—	3600 RPM	Higher speeds on request
Seal Type	—	—	Single Cartridge, Reverse-Balanced
Spring Design	—	—	Multi Spring Arrangement

 

 

 

 

 

 

Materials; 

Component	Standard Material	Optional Material	Comment
Seal Faces	Carbon / Silicon Carbide	Tungsten Carbide / Silicon Carbide	Service dependent
Elastomers	FKM (Viton)	EPDM / PTFE / FFKM	Based on chemical compatibility
Metal Parts	SS 316	Hastelloy / Duplex SS / Alloy 20	Corrosion-resistant options
Springs	SS 316	Hastelloy C	Suitable for corrosive services

 

Applications; 

• Chemical process pumps 

• Steel and mining process pumps 

• Petrochemical and refinery services 

• Pharmaceutical production systems 

• Oil & gas auxiliary rotating equipment 

• Food & beverage processing equipment 

• Industrial blowers and rotary equipment 

• Water and wastewater treatment pumps 

• Chilling plants and solvent recovery systems 

• Pulp & paper stock and chemical handling systems 

 

 

Operating Limits; 

Parameter	Value
Pressure	Up to 40 bar (580 psi)
Temperature	-40°C to +220°C (-40°F to +428°F)
Speed	Up to 3600 RPM
Size Range	20 mm to 300 mm (0.750” to 12.000”)

 

Engineering Note: Operating parameters and material selections shown above represent standard industrial configurations inferred from typical reverse-balanced cartridge seal applications. Final selection should be verified based on actual fluid characteristics, shaft dynamics, pressure-temperature conditions, and API/ANSI equipment requirements.