Flowmeter Freezing????

By Inertia Date 05-18-2001 01:37

[deleted]

By sparx

Date 06-15-2001 21:01

A standard flow meter should not freeze up when using an argon/co2 mix unless it is almost entirely co2. there is most likely a problem with the flowmeter getting moisture in the flowtube for it to freeze, especially at the lower flow rates that you are using. to tig weld aluminum, pure argon is the best to use, unless you are working on heavier sections where an argon/helium blend will work. as for tig welding steel, pure argon would be the way to go there also. CO2 is not required when tig welding

By RonG

Date 06-15-2001 22:37

Where are you getting your gas? From a liquid storage tank? There is no reason for it to freeze out side at that flow rate let alone on the inside.

What is this "Flow meter/ Regulator" combination? You can not regulate pressure with a flow meter nor flow with a pressure regulator. A flow meter has to have a set pressure at all times in order to acurratly contol the flow. I have never heard of such a thing. If you dont belive me look a real flowmeter over real close. The highest factory setting I haver seen is 50 PSI, most are 25. How could you expect it give an accurate flow if the pressure is constantly changing.

The freezing is a simple exchange of heat and should take place first at junction where the gas can increase its velocity it absorbs the heat of what ever is its conveyence (hose, pipe or fitting) but it will not form frost unless it can flow threw faster than the heat can be replaced.

But for it to freeze inside the glass you would all most have to be letting liquid inter the meter. If you are useing a normal industial cylinder it should only contain gas not liquid but just about any compressed gas will absorb energy when its released. you almost have to be using it at a greater flow than 20 CFH. Hell we run over 35 CFH a lot and only get a little frost at elbows when the air is cool and damp.

I would take another look at the metering device or you source.

By BankerQC (*)

Date 06-30-2001 11:14

We ran into a similer problem here in the shop with a 75/25 , co2 ar. mix gas. It turned out that the cylinder had been improperly refilled by our weld consumables supplier. They came in, took the regulater off and cracked the valve on the cylander and immediatly said, "our Bad, we'll have it replaced in 15 minutes". Sounds like that might be one of the first things to check.