Stationary Metal Bellow Single Cartridge Mechanical Seal

Product Overview; 

The BC730 is a high‑performance stationary metal bellows single cartridge mechanical seal designed as a fully pre‑assembled, ready‑to‑install unit for severe‑duty hydrocarbon and high‑temperature process services. Its stationary cartridge architecture enables quick, reliable installation with preset working length, significantly reducing equipment downtime and improving operational efficiency across plant‑wide deployments. 

 

Utilising a welded multi‑ply metal bellows assembly, the BC730 eliminates dynamic secondary elastomers, removing common failure modes such as O‑ring hardening, cracking and hang‑up in extreme temperature and aggressive chemical environments. The stationary bellows and seal face are fixed in the gland, so the rotating hardware runs against them; this configuration minimises the influence of shaft run‑out, deflection and vibration, maintaining precise face alignment and stable tracking for extended operational reliability. 

 

Engineered for petrochemical processing, refinery operations, thermic‑fluid circulation systems and hazardous chemical transfer duties, the BC730 delivers superior sealing integrity in applications involving hot oils, hydrocarbons, LPG, fatty acids, volatile solvents and other aggressive process media. A hydraulically balanced face geometry reduces face loading and heat generation, improving seal stability and life under severe thermal cycling, pressure transients and low‑lubricity conditions typical of refinery and hydrocarbon‑processing services. 

 

Supplied as a cartridge‑mounted assembly, the BC730 requires no on‑site axial setting; factory precision assembly eliminates installation errors and shortens maintenance turnaround, making it ideal for standardisation on critical rotating equipment. The robust, compact design supports continuous‑duty operation in power generation, steel, mining and allied industries as well as oil and gas applications. In addition to new units, we offer extensive expertise in the repair, refurbishment and reconditioning of stationary metal bellows mechanical seals, helping operators extend seal life, restore performance and reduce overall maintenance costs in high‑temperature and hazardous‑service pumping systems. 

 

Here is a single, merged Technical Features section for the BC730 stationary metal bellows single cartridge seal, ready to use on your website or datasheet. 

 

Technical Features; 

• Integrated flushing and quenching connections provide built‑in ports for auxiliary piping, enabling effective cooling, cleaning or containment to meet specific system and environmental requirements. 

• Welded multi‑ply metal bellows provide high resistance to thermal fatigue and corrosion, making the seal suitable for continuous‑duty operation in severe chemical, hydrocarbon and high‑temperature applications. 

• API 682 4th Edition–compliant design and availability of API‑compatible flush and quench arrangements ensure suitability for critical oil and gas and refinery services where standardised seal solutions are required. 

• Hydraulically balanced seal faces reduce face loading and heat generation, improving thermal stability and seal reliability under pressure and temperature cycling typical of hot‑oil, thermic‑fluid and refinery process services. 

• Available in metric and inch shaft sizes, with bi‑directional operation independent of shaft rotation direction, supporting global compatibility and flexible installation across a wide range of pumps and rotating equipment. 

• Reduced maintenance requirements and extended operating life result from the elimination of dynamic elastomer fretting, improved thermal management and robust construction tailored for severe‑duty continuous operation. 

• Single cartridge configuration, fully factory assembled and pressure‑tested, is supplied as a preset unit for quick installation and easy removal, simplifying alignment, eliminating setting inaccuracies and reducing handling errors and downtime. 

• Stationary welded metal bellows design eliminates dynamic O‑rings and other secondary elastomers, minimising vibration sensitivity and shaft‑deflection effects while providing excellent stability in high‑temperature, viscous and hazardous media. 

 

Service Overview; 

Parameter	Value
Equipment	Process Pumps, Refinery Pumps, Thermic Fluid Pumps, Hydrocarbon Transfer Pumps
Fluid	Hydrocarbons, Hot Oil, Thermic Fluid, LPG, Hazardous Chemicals, Fatty Acids
Service Nature	High Temperature, Hazardous, Corrosive, Volatile Process Media
Operating Mode	Continuous Duty / Heavy Industrial Service

 

Specifications; 

Item	Min	Max	Typical / Notes
Shaft Size	20 mm (0.750”)	150 mm (6.000”)	Larger sizes available on request
Pressure	Vacuum	25 bar (362 psi)	Depending on seal arrangement
Temperature	-40°C (-40°F)	+400°C (+752°F)	Depends on bellow & face metallurgy
Speed	—	3600 RPM	Higher speeds available for balanced designs

 

Materials; 

Component	Standard Material	Optional Material	Comment
Seal Faces	Carbon vs Silicon Carbide	Tungsten Carbide / Silicon Carbide vs Silicon Carbide	Optimized for thermal stability
Metal Bellows	SS 316L	Hastelloy C276 / Alloy 20 / Inconel	High-temperature corrosion resistance
Secondary Seals	Graphite / Flexible Graphite	PTFE	Static sealing applications
Hardware	SS 316	Duplex SS / Hastelloy / Titanium	Based on process compatibility

 

Applications; 

• Petrochemical process pumps 

• Thermic fluid circulation pumps 

• Power plant auxiliary pump systems 

• API process pump sealing applications 

• Chemical and hazardous liquid processing 

• Fatty acid and hot oil transfer applications 

• Refinery and hydrocarbon transfer systems 

• LPG and volatile solvent handling equipment 

• High-temperature reactor circulation systems 

• Biochemical and specialty chemical processing 

 

Operating Limits; 

Parameter	Value
Pressure	Up to 25 bar (362 psi)
Temperature	-40°C to +400°C (-40°F to +752°F)
Speed	Up to 3600 RPM
Size Range	20 mm to 150 mm (0.750” to 6.000”)

 

Engineering Note; 

Operating parameters shown are typical industrial values for stationary metal bellow cartridge seals and should be verified against actual service conditions, shaft dynamics, fluid properties, and API piping plan requirements before final selection.