Need advice on FX hand pump lube

[angrybear]

[QUOTE=brassbanjo;7046453]

? what is the difference between "high pressure" and "compressed air"? all these pumps produce highly compressed air, which in the presence of a fuel (such as mineral oil)
is quite capable of sustaining combustion. It does not need to be pure oxygen, no?

Yes, it does need to be Oxygen (or Oxygen rich) for there to be a serious risk of combustion, (unless you are atomising a specific combustible fuel like diesel in an engine) the only risk with 3 in 1 in a compressed air pump is possible contamination.

Compressed air is just that it is atmospheric air compressed, and the atmosphere is 78% Nitrogen & less than 21% Oxygen, so the inert N2 acts as a "damper" to the O2 content.

I clearly stated "high pressure &/or pure Oxygen" with the Oxygen underlined.

Oxygen and Compressed Air are two hugely different things and have markedly different characteristics under pressure, while pure Oxygen is volatile even at atmospheric pressure.

[brassbanjo]

[QUOTE=angrybear;7046817]

Yes, it does need to be Oxygen (or Oxygen rich) for there to be a serious risk of combustion, (unless you are atomising a specific combustible fuel like diesel in an engine) the only risk with 3 in 1 in a compressed air pump is possible contamination.

Not being funny or anything, but there have been fatal accidents where people have been messing with high pressure AIR (not oxygen) and unsuitable oils
like mineral oil. I haven't heard of an accident involving pumps specifically, but certainly people have been killed attempting to top up paintball tanks from a HPA tank.

The typical scenario is that people are attempting a field repair to the leaky fill valve of a paintball tank by squirting a few drops of oil on the o-ring in there (rather than having to wait till the next day to replace the o-ring). The air from the HPA tank then blows the oil inside the paintball tank and explosions occur.

What makes you so sure this cannot happen with a pump?

[slow_runner]

I came upon this 'SuperLube Synthetic Grease' http://www.guncity.com/superlube-syn...-85-gr.-117304

We're giving it a bash. Certainly the pumping effort has been reduced markedly so we will see how it performs over the long term.


The debate about mineral oils (fuel), high pressure/temperature, oxygen/air ratios would seem to be deserving of a thread on its own?

[oliver13]

I use silicone grease on my pump, there's no metal to metal contact, it's all metal to O ring sliding surfaces.


'The debate about mineral oils (fuel), high pressure/temperature, oxygen/air ratios would seem to be deserving of a thread on its own?'

Instead of starting a new thread on the subject, just Google 'high pressure air mineral oil explosion risk':

https://www.google.co.uk/webhp?ei=f2...explosion+risk

It's not really something that needs discussion, it is what it is.

[slow_runner]

Yep, and the explosive nature of flour is a thing to observe.
The suggestion of a separate thread was for BB and Angry or anyone else who might require a vigorous debate

[oliver13]

What's to debate? It's the laws of physics & chemistry, debate with them - & good luck...

[bighit]

I came upon this 'SuperLube Synthetic Grease' http://www.guncity.com/superlube-syn...-85-gr.-117304

We're giving it a bash. Certainly the pumping effort has been reduced markedly so we will see how it performs over the long term.


The debate about mineral oils (fuel), high pressure/temperature, oxygen/air ratios would seem to be deserving of a thread on its own?

We used that lube for diesel driven compressors. No problem with it. I still have some in my toolbox.

[Nessmuk]

Compressed air is just that it is atmospheric air compressed, and the atmosphere is 78% Nitrogen & less than 21% Oxygen, so the inert N2 acts as a "damper" to the O2 content.

Doesn't stop internal combustion engines from working does it? They only get their oxygen from the atmosphere. I'd say it's unlikely you'd end up with the right oil and compressed air mix for it to combust, but there must be a small chance that you could, surely? Worth avoiding the wrong oil for that reason I would think.

[angrybear]

Doesn't stop internal combustion engines from working does it? They only get their oxygen from the atmosphere. I'd say it's unlikely you'd end up with the right oil and compressed air mix for it to combust, but there must be a small chance that you could, surely? Worth avoiding the wrong oil for that reason I would think.

True, but petrol engines require a spark to ignite the mixture and diesel engines require the fuel to be injected, atomised at high pressure and a precise measure. (as I stated in the line above the one you quoted )

Anything with a reasonably high calorific value can be made to combust if precisely the correct conditions are met, as slow_runner intimates a cloud of flour can be ignited with spectacular results, however that does not mean that a smear of 3in1 on a pump seal is going to.

[slow_runner]

More help needed thanks.
Despite being stripped down, cleaned, then carefully reassembled, the pump will only attain 150bar.
All manner of O ring grades have been tried to no avail. So now we are back to original spec with no change in behaviour of the pump.
Would we be correct in assuming that 150bar is the 2nd stage limit and the problem could exist somewhere in the final stage? But where, why?
Has anyone had similar results and what was the solution?

It is driving Jeff crazy; I'm Ok as I am there already

[smudger1234]

More help needed thanks.
Despite being stripped down, cleaned, then carefully reassembled, the pump will only attain 150bar.
All manner of O ring grades have been tried to no avail. So now we are back to original spec with no change in behaviour of the pump.
Would we be correct in assuming that 150bar is the 2nd stage limit and the problem could exist somewhere in the final stage? But where, why?
Has anyone had similar results and what was the solution?

It is driving Jeff crazy; I'm Ok as I am there already

I would check the final stage seal. This is the one most people substitute out for a cheaper commonly available o ring, needs to be the original PU spec; nitrile and viton dont cut it.

[slow_runner]

I would check the final stage seal. This is the one most people substitute out for a cheaper commonly available o ring, needs to be the original PU spec; nitrile and viton dont cut it.

Thanks for the advice smudger.
All the seals are as per the FX recommendation; the final stage seal is PUR90 grade.
In that regard our local supplier, Seal House, have been very accommodating with advice and service.

[angrybear]

How are you testing the pressure ? have you blanked it with a brass plug or are you trying it on a rifle ?

Could it be that the adaptor is leaking rather than the pump ?

[Neil54]

When cleaning model aircraft engines, they would fire and run on WD40, also 3in1 I seem to remember.
Models use caster oil as a lubricant. I wouldn't put it in your pump though, dries to a sticky mess.

Lubricate with silicon based products.

[keithy]

If you read the info on the 3 in 1 container it says; contains petroleum distillates don't use near heat, from memory I remember my BSA meteor giving a loud crack if I put 3 in 1 down the transfer port. I definitely wouldnt use 3 in 1 in a pump pumping at 200 bar (3200 psi).