Don’t Make Seals Your Scapegoat
Seal failure could indicate a more severe problem elsewhere in your system
A mechanical seal failure is commonly credited as the cause of centrifugal pump downtime and unscheduled maintenance. A compromised seal can lead to pump wear, scratching, corrosion, flashing or fretting, so it’s vital that they perform effectively.
When seals stop sealing, maintenance teams might blame the seal itself, but by focusing only on the seal, they could be overlooking a more severe issue elsewhere in the system.
Consider this analogy: just because a car arrives at the mechanic with a smashed bumper doesn’t mean the bumper was defective. Investigate the cause of the bumper damage and you might discover an icy road is to blame. Perhaps the breaks or tires are faulty, or maybe it was operator error or a lead foot that turned the bumper into a twisted heap of chrome. Or it could be a combination of all of these factors. But the bumper could be an indicator of another, more serious issue.
Just like that bumper, discovering the cause of a seal failure requires a little more investigation.
Mechanical seals don’t operate in isolation. They’re installed into equipment, exposed to specific processes, and subjected to aggressive operating practices. It is true that customers must select the correct seal for a particular application, but there are additional requirements to ensure maximum seal reliability.
Operators, reliability engineers and maintenance personnel should confirm the following are correct:
- Application conditions and user expectations
- Seal installation
- Selection, design and installation of the sealing system (or piping plans)
- Condition and alignment of the pump or rotating equipment
- Commissioning procedures
- Pump operation within its recommended operating range
- Maintenance of the pump and sealing system
Seals do wear out and become compromised, but the vast majority of seal failures occur because of problems in other parts of the system or as a result of operating conditions or practices in the plant. Don’t let your assumption be that the seal is solely responsible for a failure blind you from considering other possibilities.
One way to learn how to visually identify and prevent a seal failure is with technology such as the Flowserve Seal Failure Analysis app a web-based tool reliability engineers and maintenance personnel can use to troubleshoot seal failures. With the app, teams can view high-resolution images of 60 seal failures to diagnose seal breakdowns, learn the telltale signs and typical causes of common failures, and compare this information with their specific seal problem to pinpoint its cause. If they need additional help, they can contact a local Flowserve expert directly from the app.
The key to improved seal performance and increased equipment reliability and uptime is to examine a seal failure as a system. By incorporating a more holistic approach, you can improve the performance of the entire system.