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.
Key Features
• Extreme Abrasion Resistance: Hardness close to diamond, resisting wear from sand, grit, and crystals.
• Universal Chemical Compatibility: Inert to most acids and alkalis, making it versatile for chemical plants.
• High Thermal Conductivity: Dissipates heat well, preventing face damage during upset conditions.
• Sintered vs Reaction Bonded: We offer both Sintered SiC (for extreme chemical resistance) and Reaction Bonded SiC (for cost-effective abrasion resistance).
• Flush Integration: API flush ports included in the gland for easy piping.
Extreme Durability & Wear Resistance: The Silicon Carbide (SiC) face material offers outstanding hardness, second only to diamond. This makes the mechanical shaft seal highly resistant to abrasive particles, preventing rapid face wear and extending seal life significantly compared to ceramic or carbon faces.
Superior Chemical & Thermal Stability: Silicon Carbide is highly inert, providing excellent resistance to a vast range of strong acids, alkalis, and solvents. It also maintains structural integrity and low thermal expansion at high operating temperatures, ensuring consistent performance in challenging thermal cycles.
Foolproof Cartridge Design: The mechanical shaft seal is supplied as a complete, pre-assembled cartridge unit with a pre-set working length. This design guarantees correct installation every time, dramatically reducing installation time, eliminating measurement errors, and making it ideal for maintenance teams of all skill levels.
Low Friction & Energy Efficiency: The low coefficient of friction of SiC reduces the power required to drive the seal faces, lowering operating temperatures and contributing to overall system energy efficiency. This also minimizes heat generation, which is critical for handling temperature-sensitive or volatile fluids.
Hydraulically Balanced for High Pressure: Available in balanced designs, this cartridge mechanical shaft seal can effectively manage high system pressures. The balanced geometry prevents excessive face loading, reducing heat generation and the risk of face distortion or failure under pressure, making it suitable for demanding pump applications.
Technical Specs | Materials | ||
Mediums | Chemical, Food, Oil, Petroleum, Pharmaceuticals Paper and pulp, Sewage treatment | Stationary Ring | Carbon/Sic/Ssic/TC |
Temperature | Elastomer Dependent | Rotary Ring | Sic/Ssic/TC |
Pressure | ≤2.8MPa | Secondary Seal | Viton/EPDM/Chemrazl Kalrez/Aflas, etc |
Speed | ≤35m/s | Spring and Metal Part | Stainless Steel/Hast C |


Product Specifications
| D (mm) | D1 | D2 | L1 | L3 | a |
| 50 | 95 | 180 | 37.6 | 17.5 | 113 |
| 55 | 100 | 185 | 37.6 | 17.5 | 118 |
| 60 | 105 | 190 | 37.6 | 17.5 | 123 |
| 65 | 110 | 195 | 39.6 | 17.5 | 128 |
| 70 | 115 | 200 | 39.6 | 17.5 | 133 |
| 75 | 120 | 205 | 39.6 | 17.5 | 138 |
| 80 | 125 | 210 | 39.6 | 17.5 | 143 |
| 85 | 130 | 215 | 39.6 | 21.5 | 148 |
| 90 | 135 | 220 | 39.6 | 21.5 | 153 |
| 95 | 140 | 225 | 39.6 | 21.5 | 158 |
| 100 | 145 | 230 | 38.6 | 21.5 | 163 |
| 105 | 150 | 235 | 38.6 | 21.5 | 168 |
| 110 | 155 | 240 | 38.6 | 21.5 | 173 |
| 115 | 160 | 245 | 38.6 | 21.5 | 178 |
| 120 | 165 | 250 | 38.6 | 21.5 | 183 |
| 125 | 170 | 255 | 38.6 | 21.5 | 188 |
| 130 | 175 | 260 | 38.6 | 21.5 | 193 |
| 135 | 180 | 265 | 38.6 | 21.5 | 198 |
| 140 | 185 | 270 | 38.6 | 21.5 | 203 |
| 145 | 190 | 275 | 38.6 | 21.5 | 208 |
| 150 | 195 | 280 | 38.6 | 21.5 | 213 |
| 155 | 200 | 285 | 38.6 | 21.5 | 218 |
| 160 | 205 | 290 | 38.6 | 21.5 | 223 |
| 165 | 210 | 295 | 38.6 | 21.5 | 228 |
| 170 | 215 | 300 | 38.6 | 21.5 | 233 |
| 175 | 220 | 305 | 38.6 | 21.5 | 238 |
| 180 | 225 | 310 | 38.6 | 21.5 | 243 |
| 185 | 230 | 315 | 38.6 | 21.5 | 248 |
| 190 | 235 | 320 | 38.6 | 21.5 | 253 |
| 195 | 240 | 325 | 38.6 | 21.5 | 258 |
| 200 | 245 | 330 | 38.6 | 21.5 | 263 |
| 205 | 250 | 335 | 38.6 | 21.5 | 268 |
| 210 | 255 | 340 | 38.6 | 21.5 | 273 |
| 215 | 260 | 345 | 38.6 | 21.5 | 278 |
| 220 | 265 | 350 | 38.6 | 21.5 | 283 |
Workshop
This workshop is equipped with professional processing equipment and integrated with standardized material warehousing management, enabling a one-stop production process from precision machining to finished product delivery. It ensures part machining accuracy and production efficiency, meeting various high-specification manufacturing requirements.




Product Research, Development and Testing
Our Product R&D and Testing focuses on optimizing seal performance through advanced simulation and material analysis. All seals undergo rigorous trials, including thermal cycling and pressure tests, to ensure durability, minimal leakage, and long service life in demanding industrial environments.




Industry Solutions




Case Study
Paint Factory Abrasion Solution: Pigments were destroying ceramic seals weekly in a paint manufacturing plant. We installed our SiC/SiC cartridge extended MTBF to 14 months.
Testimonials
We strictly use Miaoyu's Silicon Carbide seals for our slurry pumps. The wear life is incredible compared to carbon.
—Plant Manager, Fertilizer Plant
FAQs about Metal Bellows Seals for High Temperature Pumps
Q: Is Silicon Carbide (SiC) better than Tungsten Carbide (TC)?
A: It depends on the application. SiC is harder, lighter, and has better chemical resistance against acids, making it ideal for chemical and general industrial use. TC is tougher and better at handling impact shock, which makes it preferred for heavy-duty mining slurries where large rocks might impact the seal.

Our company is specialized in the production of sealing materials, mechanical seals , cartridge seals.
E-mail: gechacha@aliyun.com
Mobile: +86-18758835650
WhatsApp: +86-18758835650
Add: No8-2, Jinsha road Yuelin Street, Fenghua District, Ningbo, Zhejiang