6 Signs Your Mechanical Seals Are About To Fail

A mechanical seal prevents the water that is being pumped from entering the bearing housing of a centrifugal pump and reduces the emission of liquid outside the machine, preventing any visible leakage. With a mechanical seal, the equipment’s integrity is protected, which makes it last longer.
As mechanical seals are exposed to many different conditions during pump operation, the risk of pump failure is high – which can cause unnecessary downtime. Watch out for the following warning signs and you’ll be able to avoid mechanical seal failure and all its associated costs:

1. Grooves or notches on the seal
If you notice grooves or notches on the face of the seal, it’s a warning sign that your mechanical seal might be under excessive pressure, which can cause it to fail. This could be from inadequate lubrication or abrasive materials which can grind a groove into the seal face.
So, what do you do now?
You’ll need to take immediate action. Flush the seal using the correct seal flush plan (this needs to have sufficient lubrication at a steady flow). Use seal face materials that can manage abrasive materials in the process fluid.

2. Squealing or popping sound
If your mechanical seal makes a squealing sound during operation there may be inadequate liquid to lubricate the seal faces, which means you should enlarge the flush line or increase the orifice size. The seal may also split and splutter during operation, which creates a popping sound that indicates an insufficient liquid environment for the product.

3. Uneven wear track
An uneven wear pattern usually indicates distortion of the seal ring due to it being too tight, excessive clamping or too much pressure. Temperatures that are too high, or where the hard face is not wide enough, are also causes of uneven wear. Make sure that your seal runs properly by correctly installing it and ensuring appropriate operating conditions.

4. Fractured or cracked seal face
A seal face can fracture or crack due to mechanical seal impact and thermal shock. Avoid over-tightening when tightening fasteners and maintain a consistent seal flush plan that is appropriate to the seal and its process.

5. A cracked or chipped seal ring
The seal ring can crack or chip due to incorrect installation or incorrect handling of seal parts. Make sure that you follow the recommended installation guidelines to avoid any issues with the seal ring, and avoid brittle seal face materials.

6. An accumulation of carbon dust on the outside of the seal
Carbon dust accumulating on the outside of the seal is a sign of insufficient liquid to lubricate the seal faces, or liquid film vaporising between the seal faces. Adjust pressure in the seal chamber as the pressure may be too low for the seal type.

If you’re experiencing recurring mechanical seal failures, please call our toll-free number 1-800- 367-4180. We have experts on hand to help you choose, install, and maintain a variety of equipment.