Thread: Water pump

Sorry if this is on the wrong thread.

I have a water pump that isn't working properly. In fact the pressure tank is empty of gas. It says, on the tank, to refill with nitrogen to prevent rust. That is where my trouble is. I can't find a supply. The fill valve is the same as on a car tyre. Can I fill with air, using a foot pump ? If so will that cause rust problems at a later date ? The gas pressure is for 1.0KG Cm3. Is there a scale that converts that to bar pressure ? Thanks.

It is Obvious from the replies to this thread that there is a slight lack of knowledge with respect to SI Units and basic Process parameters.

1 KG/CM2 = 0.98067 Bar = 1000 CM Water column = 14.223 PSI
1.0197 KG/CM2 = 1 = 1019.7 CM Water column = 14.504 PSI

KG/CM3 is the SI Unit of Density, but the most dense material know to man is Depleted Uranium with a Density of 19.1 g/CM3 = 0.0191 KG/CM3 so obviously that is incorrect .

KG/Cm3 is not SI for Displacement or should I say mass / Volumetric Flow to use its correct descriptor, that is measured in KG/Cm3/s, now 1 Liter of water is 1000Cm3 therefore 1Kg/Cm3 /s equates to a volumetric flow of 1 Liter every 16 minutes and 40 seconds which would not be much of a pump.


Oxygen is a wet gas 5555555

Any element has its 3 Stages, Solid, Liquid, Gas, Oxygen melting point is -218.79 °C and boiling point is -182.95 °C whereas for Nitrogen its -210.00 °C and -195.79 °C respectively so I can assure you that oxygen is as just as dry as nitrogen at Thai Ambient Conditions. Nitrogen is an INERT Gas and as such prevents oxidation occurring, Oxidation is the process where Oxygen and Water react to form rust.

Anyway after the brief engineering refresher back to the OP.

Use a foot pump and pressurise to approx 1 Bar, slight Oxidation will occur in the pressure vessel but the rate should not be detremental to the overall lifecycle of the pump.