Precursors to Mechanical Seal Failure

By Published On: September 12, 2023

 

In the intricate world of industrial machinery, mechanical seals play a pivotal role in ensuring that fluids don’t leak from rotating equipment like pumps and mixers. They are the unsung heroes, maintaining efficiency, ensuring safety, and prolonging the life of the equipment. But like all components, they’re not invincible. Over time, due to various reasons, a mechanical seal can begin to fail. Recognizing the early signs of failure is crucial not only to maintain the equipment’s efficiency but also to prevent costly breakdowns and potential safety hazards. In this article, we’ll delve into the indicators of a failing mechanical seal and offer guidance on when it’s more beneficial to replace rather than repair.

 

Signs of a Failing Mechanical Seal:

Unusual Noises: If you start hearing abnormal noises like grinding or squealing from the equipment, it might indicate that the seal faces are damaged or that there’s an issue with the seal’s alignment. These noises in most instances come from bearings. Which lead to vibration.

Excessive Vibration: Vibration can be an enemy of mechanical seals. If you notice excessive or unusual vibrations, the most common cause is misalignment of pump to motor. 

It is easy to feel pump vibration or to hear unusual noise from rotating equipment, pay attention to equipment that is running properly and you will notice unusual noises when they occur. 

For businesses reliant on rotating equipment, understanding these warning signs is crucial. Ignoring them can lead to prolonged downtimes, increased repair costs, and potential safety hazards. While repairs can sometimes address these issues, there’s a strong case to be made for opting for quality replacement parts. At Platinum Performance Products, we advocate for proactive maintenance and believe that choosing high-quality replacement parts can often be more cost-effective and reliable in the long run than repairs.

How Do You Stop A Mechanical Seal From Leaking?

A mechanical seal’s primary function is to prevent leakage; hence, when it starts to leak, it’s a clear indication that something is amiss. Addressing a leaky mechanical seal promptly can save valuable time, money, and resources. Here are some expert recommendations to address and prevent leaks in mechanical seals:

Correct Installation: It might sound basic, but many seal failures stem from incorrect installation. Always ensure that the seal is installed according to the manufacturer’s guidelines. Pay attention to details such as seal face loading, torque settings, and orientation.

Choose the Right Seal Material: The seal’s material should be compatible with the fluid it will be containing. Incompatibility can lead to corrosion or degradation of the seal, resulting in leaks.

Maintain Proper Lubrication: The seal faces require adequate lubrication to operate effectively. Ensuring that the lubrication film is maintained will minimize friction and reduce the wear on the seal faces.

Regular Inspection and Maintenance: Periodic inspection can help identify wear patterns or damages in the early stages. By addressing these issues promptly, you can prevent leaks and extend the lifespan of the seal.

Avoid Dry Running: Running equipment without the fluid not only increases the chances of overheating but can also cause the seal faces to wear out quickly due to increased friction.

Ensure Proper Alignment: Misalignment is a common culprit behind mechanical seal leakage. Regularly check and ensure that the shaft and seal are aligned properly to prevent undue stress on the seal.

Operate Within Design Limits: Every mechanical seal is designed to operate within specific pressure, temperature, and speed limits. Exceeding these limits can compromise the integrity of the seal and lead to leaks.

Replace Worn-Out Components: Regular wear and tear can degrade the seal’s components over time. Replacing worn-out parts with high-quality replacements, like those offered by Platinum Performance Products, can ensure the seal functions optimally and prevents leaks.

In conclusion, stopping a mechanical seal from leaking primarily involves a combination of proper installation, regular maintenance, and using the right components. It’s always beneficial to invest in quality replacement parts, as they can offer a better return on investment by ensuring long-term reliability and performance.

 

What Is The Normal Leakage Rate For Mechanical Seals?

Understanding the normal leakage rate for mechanical seals is essential for gauging their performance and ensuring the safety and efficiency of the equipment they’re installed in. While the ideal scenario would be zero leakage, in reality, some minimal leakage is often considered acceptable, depending on the seal design and application.

API Standards: The American Petroleum Institute (API) sets forth standards that many industries rely upon. For certain types of mechanical seals used in refineries and petrochemical plants, the API 682 standard stipulates that the acceptable leakage rate for mechanical seals is 0.5 ml per hour for single seals and 1.0 ml per hour for dual seals under specific test conditions.

Vapor Leakage: Some mechanical seals, especially those used in high-temperature applications or with volatile fluids, might exhibit vapor leakage. This is when the fluid near the seal faces gets heated and vaporizes, resulting in a minimal and often acceptable amount of vapor escaping.

Design Factors: The acceptable leakage rate can also depend on the specific design and purpose of the seal. For instance, certain heavy-duty or cartridge seals might have different acceptable leakage rates compared to standard ones.

Application and Fluid Type: The type of fluid being sealed plays a significant role in determining acceptable leakage rates. For instance, sealing water might have a different acceptable leakage rate compared to sealing hazardous chemicals or gases.

Environmental and Safety Considerations: For industries dealing with hazardous or environmentally harmful substances, the acceptable leakage rate might be much lower, nearing zero, to ensure safety and environmental compliance.

It’s crucial to note that while minimal leakage might be deemed “acceptable” in some scenarios, consistent or increasing leakage should be addressed. Continuous leakage can be indicative of wear, damage, or other issues with the mechanical seal that might require attention.

At Platinum Performance Products, we believe in providing high-quality replacement parts that not only meet but often exceed industry standards. By opting for superior replacement parts, businesses can ensure the longevity, safety, and efficiency of their equipment, minimizing unexpected downtimes and maintenance costs.