Product Goes Solid ! 1

[Milkboy]

Hey Group

I'm seeing a SiC v SiC cartridge seal on 'glue'
having the faces broken araoung the slots on start up
as the product is going solid in the stuffing box area

The pump is a PC type and is going thru a lot of stop / starting at the moment - in the past the SiC v SiC was fine as the pump was run almost constant.

A move to Tung v SiC or Tung v Tung is planned
but I was wondering if there are alternatives
which have seen good results.

i.e. A Plan 32 External Flush (maybe only on STOP),
A devise to stop the dry product 'grabbing' the faces
A method of removing fluid from the box on stop

TIA

The Milkboy



-
Milkboy

 

[Milkboy]

I should add that I am not keen on Tung v Tung as have always thought this a bad combo

The lube for the faces comes from a barrier as the seal
is a double cartridge

TIA

-
Milkboy

 

[longeron]

What is the product again? What kind of pump again? Just a little more information.

I agree, Tungsten on Tungsten is not a face combination that I suggest.

 

[Milkboy]

The product is Glue basically

Like the glue kids use at school
PVA Glue ?

Hence the pump is a Prog. Cav.


Seal was fine for years when one batch
was run thru and then flushed clean I assume

Now when its stop/started the product
sets around the faces

On start up, the faces are broken around
the drive slots


-
Milkboy

 

[longeron]

You're alreay using a Plan 53. So you've found a compatible fluid to lubricate the seals. Good.

The reason to switch from SiC to WC was due to the drive pin or lugs crashing into and cracking the SiC. There are other metallic face materials such as bronze and Ni-Resist. But I tend to steer clear of them.

I'm not sure if your operations folks would buy into a Plan 32. It can be a hard sell. A Plan 32 with a close tolerance throat bushing to contain the foreign fluid could work.

A second option is a cousin of the dry gas seal. This kind of seal actually pumps the compatible fluid across the seal faces. Leakage can be much less than the double seal.