Avoid Premature Mechanical Pump Seal Replacement With These Best Practices

avoiding premature pump seal replacement

Petrochem refinery budgets are looking grim these days—especially in the California Bay Area where the coronavirus and social restrictions have been some of the most severe in the country. Many plants, like Martinez Marathon, have been idled while others are at least partially idled. It’s time to tighten some belts around here.

And the first line item cost you should scrutinize is mechanical seal failure. When it happens, you are not just looking at the price tag of pump seal replacement. You might also expect to shell out for bearing replacement, shaft rebalancing, or other pump rebuild costs. Even worse, your budget may have to absorb the expense of unplanned downtime—a $6.6 billion expenditure for U.S. refineries alone. And, most of the time, it’s avoidable.

That’s why it’s best to get ahead of the problem with good preventative maintenance practices.

Seal support systems, especially, are an important part of ensuring a pump’s mechanical seals have good lubrication and heat removal. If these goals are not being met, a mechanical seal will fail. If other pump problems are creating heat as well, a well functioning seal support system may help ameliorate the problem until you can fix it. They are the lifeblood of a mechanical seal system.

Ensuring seal support systems are up for the job is one of the most important ways to protect your mechanical seals and lower lifecycle costs of your pumping equipment. That’s why you’ll want to follow these best practices during reliability maintenance checks to achieve a long and reliable pump life with lower lifecycle costs.

Check Seal Support Systems to Avoid Costly Pump Seal Replacement

The mechanical seals and support systems are an important part of “keeping it in the pipes.” That is why there are so many double seal systems out there in Bay Area refineries. Leaks can lead to fires, violations, and personnel exposure, none of which are acceptable in a modern refinery.

To keep the seal support systems running smoothly and proactively address any problems, there can be a lot to check. Here are the main areas to take a look at regularly.

Flow

Problem	The seal system must deliver sufficient flow and you need a reliable way to verify it.
Effects	Insufficient cooling or lubrication from lack of flow will lead to heat checking or, worse, blistering on the seal faces or coking in the seal, and eventual seal failure.
Solution	Install proper instrumentation to verify flow or pressure.

Cooling

Problem	It’s mission-critical that the seal support system is capable of delivering the required cooling.
Effects	Just as with poor flow, you will get heat checking, blistering or coking in the seal—and eventual seal failure
Solution	Verify flow and temperatures. A slow decrease in performance means that the coolers may have internal blockages from excess scale and need cleaning or replacement. But if you’ve always recorded a lack of performance, the external cooler may be undersized and need replacement.

Instrumentation

Problem	If you don’t have proper instrumentation installed, how will you know a seal support system is functioning properly?
Effects	If a seal system is not functioning correctly and you don’t know it, it will eventually result in a surprise failure—and potential costly unplanned downtime.
Solution	Seal support system instrumentation should have regular planned testing and maintenance scheduled. It’s time to call the vendor.

Lubrication

Problem	Proper lubrication to the moving parts of the mechanical seal with the appropriate barrier or buffer fluid is fundamental to operations.
Effects	Hotter than expected fluid returning and, critically, heat checking on the surface seal faces will develop. The seal will eventually fail.
Solution	Verify the buffer or barrier fluid is suitable for the current service by putting a call in to your local vendor. If not, a fluid upgrade may be necessary.

Compatibility

Problem	Barrier or buffer fluids that don’t match the service means you have a big incompatibility problem.
Effects	Incompatibility will result in heat and lubrication damage to seals such as heat checking, coking, and, again, FAILURE.
Solution	Verify process fluid and conditions. As Bay Area refineries have changed crude slates, you may also need to change barrier/ buffer fluids or upgrade seal systems to keep up.

Leak-tight

Problem	Records show a history of leaks that have not been addressed or, perhaps, an operator just smelled something ‘off.’
Effects	At worst, you’re looking at a potential fire in the unit or a serious exposure of personnel to hydrocarbons. Time to act!
Solution	Regular maintenance on your seals and seal support systems should prevent leaks and these serious incidents. If the current system isn’t working properly, you may need a new seal support system assembled.

Economics

Problem	Too many legacy systems use water as a barrier fluid because it was cheap to install but often results in problems. It’s typically decent at heat removal but often is a poor lubricant.
Effects	Heat checking is a common result.
Solution	There are a multitude of modern, engineered fluids that could help lower pump lifecycle costs. Check with your vendor to find the right one.

There is a lot to look at around your seal support systems, but the effort is worthwhile. A well-performing seal system will delay pump seal replacements and help prevent potentially embarrassing failures. The right vendor can help with all the information gathering and assessment work.

Don’t think of your seal support system supplier as just another vendor; they should also be a partner in your preventative maintenance efforts.

The Best Seal Support System Partner In the Bay Area

Swagelok has an expert team ready to help evaluate your seal support systems and ensure they are functioning optimally. Whether it is just a review, minor instrumentation upgrade, or full-blown replacement fabricated and assembled, no seal support system project is too small.

Our Northern California team can be onsite or available via a ‘virtual engineering’ appointment for any Bay Area refinery as quickly as you need us. With Swagelok, you not only get access to top quality engineering—all of our team is factory trained and certified—but also some of the best tubing components and fabrication available today. You know we deliver quality because our Lifetime Warranty provides the best coverage in the industry.

Swagelok Northern California, can help you with all of your seal support system evaluation, design, and fabrication needs to help you avoid a pump seal replacement. Contact our team today by calling 510-933-6200.

About Paul Lesnau | Sales Manager, Business Development Manager, and Field Engineer

Paul holds a B.S. in Mechanical Engineering from North Dakota State University. Before joining Swagelok Northern California, he was the West Coast Regional Sales Manager for an organization based in Illinois involved in pneumatic and hydraulic applications where he supervised product distribution throughout the western United States, Canada, and Mexico. While in this role, he was able to help provide technical and application-specific expertise to customers and distribution to drive specifications.

Topics: Assembly Services Archive Seal Support Systems

Share this