Technical Knowledge

In a high-capacity pulp mill or a chemical processing plant, the clock is your most expensive enemy. When a Sulzer® APP or Ahlstar pump goes down due to a seal leak, the cost isn't just the price of the replacement part—it’s the lost production, the labor hours, and the risk of an incorrect installation.

For many maintenance teams, the biggest bottleneck is the transition from old-fashioned "component seals" to modern "cartridge seals." At FBU Sealing Technology, our 2200 series is designed to solve this exact problem, reducing your Mean Time To Repair (MTTR) significantly.

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.

You’ve installed the replacement seal, followed the torque specs, and yet, six months later, the pump is leaking again. For maintenance teams operating Sulzer® APP or Ahlstar pumps, repetitive seal failure is more than an inconvenience—it’s a drain on the plant’s profitability and a risk to operational safety.

In the demanding environment of chemical processing, the reliability of fluid handling equipment hinges on one critical component: the mechanical seal. A single seal failure can lead to costly downtime, safety hazards, and environmental compliance issues.
While seal design is vital, material science is often the deciding factor between a leak-free operation and catastrophic failure. This guide provides a technical framework for matching seal faces and elastomers to aggressive chemical media, with a specific focus on the complexities of sulfuric acid (H2​SO4).

Introduction: Mechanical seal failure is responsible for nearly 80% of centrifugal pump maintenance issues. At the heart of these failures lies the abnormal wear of the rotary and stationary rings. For engineers in the pulp, paper, and chemical industries—where equipment like Sulzer® or Andritz® pumps must run reliably—understanding these wear patterns is essential to preventing unscheduled downtime.
1. Non-Invasive Inspection: 3 Steps to Predict Failure