Anatomy of a Stuck Pump Face Seal - Carbon Side

[sdowney717]

just a few photos, I assure you the carbon is not scarred or worn down.
The spring can not push the carbon face out of the housing when assembled. Perhaps instead of housing corrosion the rubber o ring is swollen up. Anyhow it looses the ability to slide, then it jams down and wont seal.

I was thinking of an improvement that would work. Glue the carbon face into the bronze housing with rubber gasket maker (put flat rubber washer behind carbon face to align carbon ring and space it forward.)

get a spring or perhaps can use existing wavy spring and washer and put behind the ceramic face side.
That spring can then push ceramic face against stationary carbon face.

[sdowney717]

.6 may be too small if shaft is 5/8 but ok for 1/2 inch shaft
compressed length is good, what is meant by the spring rate?
saying wire diameter 45 thousands yet compressed is only 1/4 inch,
also, 8.7 lbs of force when spring fully compressed seems too much pressure, if that is what they mean.
I have seen delicate springs before anyone have another source to browse?

Amazon.com: Stainless Steel 316 Compression Spring, 0.6" OD x 0.045" Wire Size x 1" Free Length (Pack of 10): Industrial & Scientific

Spring Rate: 8.7 lbs./inch

Item Package Quantity 10
Material Type Stainless Steel 316
System of Measurement Inch
Compressed Length 0.249 inches
Outside Diameter 0.6 inches
Wire Diameter 0.045 inches

[delmarrey]

So, this fits over a 5/8" shaft, yes?

A better focused picture would be nice but I assume the wave spring goes in first, then the o-ring, carbon seal and then the brass washer to hold it all in.

Like I stated in your other thread, if you could pack it with lithium grease when it's new, that might do the trick. Also, if you could put in a second wave spring that would increase the pressure.

You could drill a hole in the side and use a syringe to inject the grease. And when it's pressed into the pocket it would seal the hole. It's kind of micro surgery but I being a Tool & Diemaker I think in small dim's. and view it as possible.

Can these be disassembled w/o damaging them?

[sdowney717]

I think its just dumb to put the spring inside the bronze carbon face seal. If you look at pool pump face seals the ceramic side is held in by a pocket with a rubber cup. The spring is on the other side to push the black carbon face against the ceramic. They are also very easy to change out. If I put an exterior spring on this it would be free to move.

Also do you think that injecting grease would swell the rubber o ring and jam the seal?
Either that or grease would allow the rubber to slide, dont know unless someone experiments.

here is a pic of a pool pump seal


the spring side has a rubber bellows design, the spring will never be impeded from pushing the carbon face forward.

[Neo]

Pump Faced Seal

[delmarrey]

Originally Posted by sdowney717

Also do you think that injecting grease would swell the rubber o ring and jam the seal?
Either that or grease would allow the rubber to slide, dont know unless someone experiments.

There are different types of o-ring materials, all are resistant to water. Here is a chart of o-ring materials, though we don't know what your seal is.
(everything you need to know about o-rings and more) >>> http://www.parker.com/literature/ORD...g_Handbook.pdf

The higher the acrylonitrile content, the better resistance to oils. But it's most likely butyl (cheapest).

I use to rebuild hydraulic equipment for the City here and I can tell you that Reciprocating Seals were always the hardest to get to seal. The surfaces have to be clean and scratch free. Once you lose the smooth surface, you lose any significant pressure behind it. I'm surprised they are using it against a carbon ring. It would have to be polished to seat, unless it were bonded.


The difference in design of face seals has to do with the design of the pump. The Jabsco's are small & w/o much space to work with.

Odd! When I look at the picture of your pump it shows a lip seal w/the o-ring on the out side surface.

.

[sdowney717]

Perhaps the lip seal you notice is the o ring inside of the white ceramic seal.
The oring seals ceramic face seal to the shaft. The ceramic seal spins with the shaft.