Leaking Mechanical Seal? Think Twice Before Tightening

Author: Sara Peters | August 16, 2017 | Category: Mechanical Seals

dripping faucetWhen the bathroom faucet is dripping, usually a little twist of the handle to tighten the internals will stop it. When a mechanical seal is leaking, however, over-tightening the fasteners can make the situation worse.

To properly install a mechanical seal, a number of precautions must be taken.

  • Reading the installation instructions is strongly advised.

  • Components should never be forced to go together. They’re easily damaged and expensive to replace.

  • Workspace and hands should be clean. Small amounts of dirt and grime will damage seal faces.

  • Don’t over torque fasteners

So the fasteners are a little tight, so what?

Overtightening puts undue stress on the mechanical seal internals. This sets the seal up for failure from mechanical shock. Mechanical shock is caused by bad bearings, cavitation, excessive torque, uneven loading, and misaligned shafts. Mechanical shock commonly occurs due to mishandling and improper assembly of the seal.

Overtightening also can compress the springs and add additional loading forces on the seal faces. This causes the seal to run hotter than it should, and most likely wear sooner than expected. 

When mechanical seal fasteners are overtightened, the stationary seal components become distorted, gaskets can be damaged or extruded, all resulting in leakage.

If a mechanical seal is leaking, restrain yourself from the natural tendency to tighten, and try loosening instead. Oftentimes this works.

How do I keep from overtightening during installation?

Check the installation manual for guidance on just how tight to fasten those bolts. Consider employing a torque wrench to ensure accuracy.

If leaking persists after ensuring proper torque on the fasteners, consider getting a mechanical seal expert involved. They may be able to save you a lot of time and frustration troubleshooting the seal.

Got a mechanical seal question? Ask us about it! We gladly provide technical assistance to businesses and municipalities in Wisconsin and upper Michigan.

Download 13 Ways To Kill A Mechanical Seal

Sara Peters

Sara Peters

Sara leads Crane Engineering's blogging team, coming up with fresh stories and insights for our readers to apply to their every day work.

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