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pump freezing (Tapflo - Double Diaphragm)

pump freezing (Tapflo - Double Diaphragm)

pump freezing (Tapflo - Double Diaphragm)

(OP)
Hi,

I posted this yesterday but for some reason the thread has disapeared?

Anyway, we have a pump that keeps freezing (five or six times a week for 10 - 20 mins) due to moisture in the compressed air. The air line comes from our drier which is very competent and well serviced but then travels across the bakery (in the roof) into the fridge where the pump is situated.

Therefore air exiting the drier is around 2 degrees Celsius, it travels approx 30m in a bakery roof,ave temp 25-30 degrees then into the fridge 2 degrees.

I assume it is picking up moisture due to the differences in temps it has to endure.

It is impossible to alter the configuration of the bakery and so the drier must stay where it is, likewise the pump.

Is there anything I can use locally (near the pump) that would eliminate all or at least most of the moisture from the air before it enters the pump and hence rectify the weekly problem we have of the pump stalling?

many thanks in advance

Beatts

RE: pump freezing (Tapflo - Double Diaphragm)

If you cool the air going into the drier you might get a drier product out which would not freeze the pump.  You might try taking the air into the drier from the refrigerated room itself.

"I am sure it can be done. I've seen it on the internet."  BigInch's favorite client.

"Being GREEN isn't easy." Kermitfrog http://www.youtube.com/watch?v=hpiIWMWWVco

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RE: pump freezing (Tapflo - Double Diaphragm)

(OP)
Hi Biginch,

Thanks but we can't put air from the fridge into the drier as its is 30m away and will be warmed up again.

RE: pump freezing (Tapflo - Double Diaphragm)

Sounds like your drier is undersized.  Do you have a knockout pot after your compressor before the air drier?

RE: pump freezing (Tapflo - Double Diaphragm)

Air at 25 °C can absorb more moisture than air at 2 °C. So, where shall the moisture come from in a closed pipeline when it leaves the drier with 2 °C and arrives at the pump with 2 °C?

ash' question is correct. Does your compressor have a knockout pot?

  

RE: pump freezing (Tapflo - Double Diaphragm)

(OP)
Hi This is the compressor in use, well actually there are two working together.

http://www.abac.co.uk/genesis-compressors.htm

It is an 11kw - 8 bar model.

The dew point is set at 2-3degrees. It comes out of the compressor at this temp and 8 bar, it then travels in an uninsulated standard rubber air hose across the bakery where it is regulated down at the fridge to 4 bar. The internal temp of the fridge is between 2 and 4 degrees. The air temp of the bakery (remember it travels approx 30 - 40m) is a minimum of 20degrees.

There is a 'knockout pot' next to the compressor, and also a small mist separator at the fridge, yet when the pump is running you can see the condensation mist being emitted from the exhaust port.


The air is used elsewhere in the bakery also for various equipment and air guns etc.

 

RE: pump freezing (Tapflo - Double Diaphragm)

Run the air through an uninsulated metal coil inside the fridge, out to the mist separator, then back in to the pump? Cool the air before it enters the mist separator to give it a better chance at removing some moisture.

Not sure how practical that really is but given the constraints...

RE: pump freezing (Tapflo - Double Diaphragm)

You are not drying the air adequately. Instrument air is dried to -40F dew point and still air gets into the lines. Flow surges (often caused by air driven pumps) do not allow the dryer to get the air fully dry. For some reason dew point meters are designed not to shows this.

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