5 Reasons Why Mechanical Seals Fail

Mechanical seals ensure that pumps do not leak, which can cause damage to the rest of the machine. The lifeline of your machine, a mechanical seal contains the fluid within machines, such as pumps and mixers, where a rotating shaft passes through a stationary housing.

The most common cause of pump downtime is a mechanical seal failure. To avoid this, it’s essential to apply the right seal for the desired, and appropriate, function.

However, the seal can be exposed to a wide variety of operating conditions, which can cause issues down the line. Sometimes operating conditions can become very different from conditions that the seal was intended for. But even if your seal is the right one for the job, there can be times when it fails faster than you anticipate. This is particularly true if you work in a plant that runs multiple functions.

Let’s look at some of the common reasons why mechanical seals fail – and help you protect your seals and them and make them last longer.

1) Letting the pump or machine run dry: A mechanical seal can easily leak or become damaged if you let your pump or machine run dry. If the seals run dry, the friction will cause heat to accumulate, and cause damage – causing thermal shock. Your seal can disintegrate just 30 seconds after heating up!

2) Too much vibration: Pump vibration can be caused by improper alignment, pump imbalance or operating the pump past its BEP (best efficiency point) – which means it’s operating beyond its normal working point. These vibrations damage the machine and lead to reduced seal life

3) Hammering couplings: Many machines contain components like pistons that have a hammering action, sometimes so intense that it produces a lot of vibration and movement. This can cause problems not only for the machine but also for the seals.

4) Human error: Simple human mistakes can cause the seals to fail. For example, not starting the machine up properly can cause the motor to trip and the shaft to twist, causing movement that results in internal parts coming into contact, seal failure, and even reduce the life of bearings. Other human errors that can cause seals to fail include improper installation of the seal, failing to clean the areas surrounding the seal, and lack of proper maintenance. Oil, dirt and even fingerprints can damage the seal, so it’s important to exercise due diligence when it comes to seal care!

5) Using the wrong seal: It’s important to find the right seal for the job, which means selecting the appropriate seal for the machine that you’re using. However, even seasoned engineers can get it wrong, which leads to errors during installations. Different machines or pumps require different types of seals and are built to handle different materials. Using a abrasive material can also reduce the lifespan of a seal.

If your seals are still failing after eliminating the above, or you’re experiencing regular mechanical seal failure, maybe it’s time to call in an experienced engineer. They will help you identify the problem and suggest ways to extend the lifespan of your machine. We’re on hand if you need us – we have experts on hand to help you choose, install, and maintain a variety of equipment. For more information, call our toll-free number 1-800-367-4180.