Views: 0 Author: Site Editor Publish Time: 2026-04-29 Origin: Site
In the heart of a Sulzer® APP or Ahlstar pump, the mechanical seal faces are separated by a fluid film thinner than a human hair. This microscopic boundary is where your pump’s reliability is won or lost. If the material choice doesn't match the media—whether it’s abrasive paper pulp or corrosive chemicals—the film breaks, the faces touch, and the seal fails.
At FBU Sealing Technology, we don't believe in "one size fits all." As your technical partner, we use material science to customize your 2200 series seals, ensuring they are optimized for your specific industrial environment.
Most OEM seals come with a "standard" material pairing. However, the standard isn't always the best for your Mean Time Between Repair (MTBR). We offer three primary face materials, each with a specific technical purpose:
Sintered Silicon Carbide (SSiC): Our gold standard for abrasive media. SSiC offers extreme hardness and high thermal conductivity. It stays cool under pressure and resists the "grinding" effect of solids in paper stock.
Tungsten Carbide (TC): While SSiC is hard, it can be brittle. In high-vibration environments or high-torque applications like Refiners (using our FBU 2295), Tungsten Carbide provides the necessary toughness to resist cracking.
Carbon-Graphite: Ideal for clean, lubricating fluids. Carbon has self-lubricating properties that prevent damage during brief dry-running periods, but it should be avoided in slurries where it will be quickly eroded.
The FBU Technical Edge: For the most extreme abrasive environments, we offer Diamond-Coated SSiC. This provides a surface nearly as hard as a natural diamond, virtually eliminating face wear in the toughest chemical-mechanical pulping (CMP) processes.
An O-ring might be the smallest part of the seal, but if it swells or degrades due to chemical incompatibility, the entire cartridge fails.
Viton (FKM): Excellent for general oil and water applications up to 180°C.
EPDM: The go-to for many paper mill applications, offering great resistance to hot water and steam.
FFKM (Perfluoroelastomer): When you are pumping aggressive acids or bases with extreme pH values, standard elastomers fail. We provide FFKM upgrades that offer near-universal chemical resistance and can handle temperatures exceeding 300°C.
Why do engineers switch from global OEM brands to FBU? Because we provide Engineering Flexibility.
Media Analysis: We don't just ask for a part number; we ask about your pH levels, solid content, and operating temperature.
Performance Upgrades: If your current seals are failing due to heat-checking, we can suggest a material upgrade (e.g., from Carbon to SSiC) that doubles your seal's life.
Traceability: Every FBU 2200 series seal comes with material certifications. You know exactly what is in your pump, ensuring compliance with ISO and plant safety standards.
1.Can I use Silicon Carbide faces for every application?
Not necessarily. While SSiC is excellent for wear resistance, it has poor "dry-run" capabilities. If your pump frequently experiences "gas-locking" or dry startups, a Carbon-to-SSiC pairing might be a safer choice for lubrication.
2.How do I know if my O-rings are failing due to chemical attack?
If your O-rings appear "swollen," "sticky," or have developed "squared edges" (compression set), the chemical media is likely attacking the polymer. It’s time to consult with FBU about an upgrade to Aflas® or FFKM.
3.Is Tungsten Carbide better than Silicon Carbide for refiner seals?
Usually, yes. Because refiners generate significant axial vibration and torque, the higher fracture toughness of Tungsten Carbide prevents the faces from shattering under mechanical shock.