SUBJECT: The most asked questions about mechanical seals 10-2

What is considered good life for a mechanical seal?

Why do most seals fail prematurely?

What are the most common causes of component damage?

What are the most common causes for the lapped seal faces to open?

Do seal faces have to be lubricated? Can they run dry?

Do seal faces have to be kept cool?

When should you use two hard faces?

Why not standardize on two hard faces?

Do seals have to leak.?

Why do most original equipment seal designs frett and damage the shaft under the dynamic elastomer or spring loaded Teflon.?

Do you have to flush most slurry applications?

I am looking for a simple solution to a difficult problem. Do discharge recirculation filters or cyclone separators installed between the pump discharge and the stuffing box make sense in slurry applications?

If I put a higher fluid pressure barrier fluid between dual seals, shouldn't that keep the faces clean?

Do you need a higher pressure barrier fluid between dual seals?

How does seal hydraulic balance work?

Is it O.K. to have a third party rebuild my mechanical seals?

Should I be using split mechanical seals?

If I touch the lapped faces, are they ruined?

Why should you not use stainless steel springs or stainless steel bellows in mechanical seals?

Why not standardize on Teflon as the preferred rubber part in a mechanical seal?

Why not mount the seal outside the stuffing box and then dirt and solids will not get into the springs and sliding parts of the mechanical seal?

What is a cartridge seal?

Do I need the new gas seals if I want to seal fugitive emissions?

Why does my outside mounted seal make a whistling sound?

Every time I remove a rubber bellows seal from my pump it is stuck to the shaft. Why?

When my metal bellows seal fails because of breakage at the plates, the break is always near the end fittings and never in the middle of the bellows. How is that explained?

® DuPont Dow elastomer

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