This wave spring seal is a modern solution for centrifugal pumps, designed for easy replacement. Its primary advantage is the combination of a PTFE bellows and a compact metal wave spring. The PTFE component provides excellent chemical resistance against highly corrosive media, acids, and alkalis, where standard elastomers would fail. 

• Edge-Welded Bellows: We use precision edge-welded leaflets which offer a higher stroke-to-length ratio and better fatigue life compared to formed bellows.

• Damped Vibration: The bellow structure inherently dampens stick-slip vibration, preventing face chattering at high temperatures.

This booster pump mechanical seal is a specialized high-performance solution designed to handle elevated temperatures and demanding operational conditions. As a metal bellows mechanical seal, it replaces traditional elastomer secondary seals with a durable, all-metal welded bellows. This innovative construction eliminates the risk of elastomer failure under thermal stress, ensuring long-term reliability. Engineered specifically as a high temperature mechanical seal, it reliably operates in hot oil, boiler feed, and chemical applications. 

Our metal bellows mechanical seal is available in standard small shaft sizes including 12mm mechanical seal, 14mm mechanical seal, 16mm mechanical seal, and 18mm mechanical seal configurations. The all-welded metal bellows design eliminates dynamic O-ring hang-up, making it suitable for hot water, light hydrocarbon, and chemical services on small centrifugal pumps and lab-scale mixers. Each size follows ISO envelope dimensions for direct OEM replacement. Custom face materials (SiC/TC/Carbon) and elastomers (Viton®/EPDM/Kalrez®) are available.

Direct Interchange: Perfect fit for OEM John Crane Type 606 dimensions.

Extreme Temperature: Reliable performance from -75°C to 400°C with standard Grafoil gaskets.

Stationary Bellows: Metal bellows mechanical seals are ideal for high-speed applications, eliminates centrifugal stress.

Standard Quench Ports: API Plan 62 ready to prevent coking and manage fugitive emissions.

• Direct Torque Transmission: Torque is transmitted directly through the bellow tail or drive collar, eliminating the need for drive pins that can wear out.

• Balanced by Design: The effective diameter of the bellow changes with pressure, providing a naturally balanced face load for varying pressures.

• Vibration Damping: The multi-ply bellow construction dampens the high-frequency vibrations often found in high-speed boiler feed pumps.

• Hydrodynamic Face Grooves (Optional): Faces can be laser-grooved to promote fluid film formation, preventing dry running in hot water.

• Self-Cleaning Rotation: The rotation of the bellow creates a strong centrifugal force that ejects solids from the seal cavity, keeping the faces clean.

• Double-Ply Options: Available in double-ply bellows for higher pressure ratings required in deep-well submersible applications.

As a specialized water pump shaft seal replacement supplier, MiaoYu Seals produces the metal bellows seal as a direct drop-in alternative to Roten Type 37 / Type E on European boiler feed and HVAC water pumps. Built with Inconel welded bellows and TC/SiC vs carbon faces, it eliminates elastomer hang-up in 180–200 °C condensate return, giving routine maintenance crews an OEM-level fit at roughly one-third the Roten brand cost. Shaft coverage 18–150 mm (0.75\"–6\"), ≤2.0 MPa, ≤23 m/s, NBR/EPDM/FKM secondary seals—exactly dimensioned for pump-shaft retrofit without machining the stuffing box.

Model NO.: Type 21 mechanical seal

Specification: 1'',1 1/4'',1 3/8'',1 5/8'',1 3/4'',1 7/8'',2 1/8'

Temperature: high temperature mechanical seal

Balance: Unbalanced

Type: Multi-Spring

Accreditation: ISO, SGS, UL, ROHS

Service: OEM/ODM

Origin: China

Interchangeable Brand: John Crane, Burg , Flowserve, AES, APV etc

Temperature: high temperature mechanical seal

Balance: Unbalanced

Type: Single Cartridge Seal

Accreditation: ISO, SGS, UL, ROHS

Service: OEM/ODM

Specification: all sizes

Origin: China

The robust graphite cartridge mechanical seal features a stationary cartridge design, it is a direct, high-performance replacement for OEM seals in water, chemical, and general industrial pumps. 

Specifically designed as a high pressure pump mechanical seal, this product combines the robustness of a cartridge design with the flexibility of component parts. Component mechanical seal is built to withstand extreme pressure differentials, aggressive media, and continuous operation, ensuring zero leakage and maximum uptime for critical pumping systems. 

The silicon cartridge mechanical shaft seal is a high-performance sealing solution engineered for reliability in the most demanding industrial applications. This robust cartridge seal features a premium Silicon Carbide (SiC) sealing face, known for its exceptional hardness, wear resistance, and thermal conductivity. Housed in a pre-assembled, factory-set cartridge, it delivers plug-and-play installation, eliminating common setup errors. Designed to withstand extreme conditions, this mechanical shaft seal provides superior containment for abrasive slurries, corrosive chemicals, and high-temperature fluids, ensuring extended equipment life and minimized downtime in centrifugal pumps, mixers, and agitators.

Rubber cartridge mechanical seals are precision-engineered sealing units designed for reliable, leak-free performance in pumps, mixers, agitators, and other rotating equipment. Manufactured by MIAOYU, these single and double mechanical seals incorporate flexible rubber bellows that eliminate the need for dynamic O-rings, making them ideal for handling abrasive fluids, slurries, and applications prone to clogging. The cartridge design provides pre-assembled, pre-set sealing solutions that ensure quick installation, reduce maintenance errors, and extend equipment uptime.

The double acting mechanical seal for caustic pumps is a robust, engineered safety system designed to provide absolute containment of sodium hydroxide (NaOH), potassium hydroxide (KOH), and other aggressive alkaline solutions. Unlike single seals, this double acting (dual pressurized) cartridge features two sets of sealing faces with a pressurized barrier fluid system (typically water or glycol) between them. This configuration ensures the process fluid cannot leak to the atmosphere, even in the unlikely event of an inner seal failure. 

Cartridge type fire pump mechanical seal is a mission-critical sealing component engineered specifically for life safety and property protection applications. Designed and manufactured to meet the most stringent global fire protection standards, including NFPA 20, UL, and FM approvals, this fire pump mechanical seal ensures the instantaneous and reliable operation of jockey pumps, electric fire pumps, and diesel-driven fire pumps. 

Cartridge grundfos pump mechanical seal is a precision-engineered aftermarket replacement designed specifically for Grundfos CR, CRI, and CRN series vertical multistage pumps. This high-performance cartridge seal features a robust rubber bellows design that eliminates axial movement, preventing shaft wear and ensuring a perfect fit without the need for special tools. 

• Thermal Shock Resistance: Our specific ceramic grade is engineered to withstand the rapid temperature changes of hot water washdowns better than standard commercial ceramics.

• Polished Metal Surfaces: All wetted metal parts are electropolished to prevent product adhesion and bacterial growth.

• Impregnation Options: We offer Resin-Impregnated Carbon (for general chemicals) and Antimony-Impregnated Carbon (for high-temp/high-pressure) to tailor the seal to your specific media.

• Hastelloy Spring Option: Springs can be upgraded to Hastelloy C-276 to prevent stress corrosion cracking in chloride-rich environments.