Jiaxing Burgmann Mechanical Seal Co., Ltd. Jiashan King Kong Branch

Selecting the right materials for mechanical seals is critical to ensuring leak-tight performance, long service life, and reliable operation in industrial applications. The selection process must be guided by the operating environment, medium characteristics, and mechanical requirements—here’s a systematic breakdown of the key principles and practices: 1. Prioritize Compatibility with the Sealed Medium The sealed medium (liquid, gas, or slurry) is the primary determinant of material selection. Focus on three core properties: - Corrosiveness: Choose corrosion-resistant materials for aggressive media (e.g., acids, alkalis, solvents). Silicon Carbide (SiC) and Tungsten Carbide (WC) excel in corrosive environments, while elastomers like Fluororubber (FKM) or Perfluoroelastomer (FFKM) resist chemical degradation better than Nitrile Rubber (NBR). - Abrasiveness: For media containing solids (e.g., slurries, pigments), opt for hard, wear-resistant face materials. Tungsten Carbide (WC) with cobalt binder or reaction-bonded Silicon Carbide (RBSC) offers superior abrasion resistance; pair with a softer carbon graphite secondary face to minimize friction. - Temperature & Pressure: High-temperature (above 200°C) or high-pressure (above 10 bar) conditions demand materials with thermal stability and mechanical strength. Silicon Carbide (SiC) maintains hardness at extreme temperatures, while PTFE (Polytetrafluoroethylene) is ideal for low-friction, high-temperature elastomer applications. 2. Ensure Seal Face Pairing Compatibility Mechanical seal faces require a "hard-soft" pairing to balance wear resistance and sealing efficiency: - Common pairings: WC vs. Carbon Graphite, SiC vs. Carbon Graphite, or SiC vs. SiC (for ultra-high purity or non-abrasive media). - Avoid pairing two hard materials (e.g., WC vs. WC) as they cause excessive friction and premature failure; avoid two soft materials (e.g., Carbon Graphite vs. Carbon Graphite) for abrasive or high-pressure scenarios. 3. Align with Operating Conditions - Rotational Speed: High-speed applications (above 3000 RPM) need materials with low friction coefficients and high thermal conductivity. SiC and WC are preferred for their ability to dissipate heat, while PTFE-filled carbon graphite reduces friction. - Shaft Runout & Misalignment: For applications with moderate shaft runout, elastomers like EPDM (Ethylene Propylene Diene Monomer) offer flexibility, while rigid face materials (SiC, WC) suit precise alignment. - Environmental Constraints: Food, pharmaceutical, or drinking water applications require FDA-approved materials (e.g., PTFE, EPDM, or 316 stainless steel metal components) to ensure non-toxicity and compliance. 4. Reference Common Material Selection Guidelines Material Type Key Advantages Typical Applications Silicon Carbide (SiC) High hardness, corrosion/wear resistance Aggressive media, high-temp/pressure systems Tungsten Carbide (WC) Exceptional abrasion resistance Slurries, abrasive fluids, heavy-duty pumps Carbon Graphite Low friction, self-lubricating Low-abrasive media, low-to-medium speed pumps Fluororubber (FKM) Chemical resistance, high temp tolerance Oil, solvents, high-temperature applications PTFE Non-stick, chemical inertness Corrosive chemicals, food-grade applications By integrating medium compatibility, face pairing logic, and operating condition alignment, you can select mechanical seal materials that optimize performance, reduce maintenance costs, and prevent unplanned downtime.   Jiaxing Burgmann Mechanical Seal Co., Ltd Email: doris@mechanicalseal.com.cn Skype: kathysunlin Fax: 86-573-84072317 Mob: 86-15381220188 WhatsApp: 8615958372402 Website: www.industrial-mechanicalseals.com Add: A-5 Wanyangzhongchuangcheng, Ganyao Town, Jiashan county, Jiaxing, Zhejiang, China. 314107

1. Process: RBSC forms via reaction bonding with residual silicon; PLSSC sinters at high temp without external pressure. 2. Density & Porosity: RBSC is low-density with porosity; PLSSC is high-density, almost fully dense. 3. Performance: RBSC has good impact resistance; PLSSC excels in hardness, corrosion resistance and high-temperature stability. 4. Cost: RBSC is cost-effective; PLSSC is more expensive due to complex process.     Jiaxing Burgmann Mechanical Seal Co., Ltd Email: doris@mechanicalseal.com.cn Skype: kathysunlin Fax: 86-573-84072317 Mob: 86-15381220188 WhatsApp: 8615958372402 Website: www.industrial-mechanicalseals.com Add: A-5 Wanyangzhongchuangcheng, Ganyao Town, Jiashan county, Jiaxing, Zhejiang, China. 314107

1. Ensure the shaft surface finish meets requirements (Ra 0.2-0.4μm) and no scratches, burrs or corrosion exist before installation. 2. Clean all seal components (stationary ring, rotating ring, spring, O-ring) with clean solvent; avoid dust, impurities or oil residue. 3. Check the perpendicularity of seal chamber end face to shaft (tolerance ≤0.05mm) and coaxiality of shaft (runout ≤0.03mm) strictly. 4. Apply appropriate food-grade lubricant to O-rings and sliding surfaces for smooth assembly; do not use lubricant containing particles. 5. Install stationary ring and rotating ring carefully, avoid collision or deformation; ensure the sealing faces fit tightly without tilting. 6. Adjust spring compression amount accurately according to technical drawing; over-compression or under-compression will cause seal failure. 7. Keep the installation direction of spring consistent; ensure no jamming during shaft rotation. 8. After assembly, rotate the shaft manually for 3-5 circles to confirm flexible rotation without stuck or abnormal noise. 9. Vent the seal chamber completely before startup to avoid air locking; ensure full medium filling in the sealing system. 10. Run the equipment at low speed first for 10-15 minutes, check for leakage, temperature rise and abnormal vibration before normal operation. 11. Avoid dry running of mechanical seal; ensure sufficient lubrication and cooling during operation. 12. Do not hit the seal components with hard tools during installation to prevent damage to sealing faces.     Jiaxing Burgmann Mechanical Seal Co., Ltd Email: doris@mechanicalseal.com.cn Skype: kathysunlin Fax: 86-573-84072317 Mob: 86-15381220188 WhatsApp: 8615958372402 Website: www.industrial-mechanicalseals.com Add: A-5 Wanyangzhongchuangcheng, Ganyao Town, Jiashan county, Jiaxing, Zhejiang, China. 314107

1. A mechanical seal is a critical component used to prevent fluid leakage in rotating equipment like pumps, mixers and compressors. 2. It mainly consists of stationary ring, rotating ring, spring, auxiliary seal and gland, forming a sealed face via precise fitting. 3. The sealed faces (rotating & stationary) are the core part, requiring high flatness to ensure tight sealing under pressure. 4. Mechanical seals are divided into single-end, double-end, balanced and unbalanced types based on structure and working principle. 5. Temperature, pressure, medium corrosiveness and rotational speed are key factors affecting mechanical seal service life. 6. Common materials for seal faces include silicon carbide, tungsten carbide, alumina ceramic and carbon graphite for good wear resistance. 7. Auxiliary seals are usually made of fluororubber, nitrile rubber or PTFE to adapt to different media and temperatures. 8. Proper installation with accurate alignment can avoid premature wear and leakage of mechanical seals. 9. Regular cleaning and lubrication of the seal area help maintain its sealing performance and extend service life. 10. Mechanical seals have better sealing effect and longer service life than traditional packing seals in industrial applications.   Jiaxing Burgmann Mechanical Seal Co., Ltd Email: doris@mechanicalseal.com.cn Skype: kathysunlin Fax: 86-573-84072317 Mob: 86-15381220188 WhatsApp: 8615958372402 Website: www.industrial-mechanicalseals.com Add: A-5 Wanyangzhongchuangcheng, Ganyao Town, Jiashan county, Jiaxing, Zhejiang, China. 314107