Solenoid Valves

1. None.

2. When they fail. Ask the manufacturer about life expectancy.

Academic articles can be found by searching for them.

Beware the link you provided is not the direct replacement. It's listed as having a 120 volt coil.

Thank you for your help.

As ozzb said you have 120V in the second link, but following the first you can see listed the 24V replacement. (basically change the "G" to an "H" in the model number) I also notice the body is formed a bit different, so you may have a plumbing fit up problem if the inlet/outlet are a bit differently spaced from the old model to the new one.

If you get the new 24V model, the solenoid will work the same, but will it fit the same?

The fraction of on time will now be 72/73 of before, which almost certainly will not be noticed.

I think you're wrong. The last 2 valve courses I've taken say that Cv is a flow factor constant particular to a valve design that is used to calculate flow rate through a valve - not on/off cycles.Thus the flow rate will be very incrementally increased.

>how often solenoid valves should be replaced?

Since you asked the question, I have to assume that you are not in an industry that replaces components on the basis of accumulated run-hours (like aircraft). Outside of those segments, solenoid valves are only replaced when they fail and repair is more costly than replacement.

ASCO's red hat series is known for its easily replaceable electrical coil assemblies. Gasket and diaphragm kits are available for those who want replace these components. I suspect that a replacement coil and parts are still available for your 'obsolete' model.

Academics concern themselves with life span of solenoid valves, because no government agency will fund them to write on such topics.

But manufacturers publish statements like, "designed for quiet operation and long life, up to 20 million cycles, in dry air or gas applications."

The reality number that I usually hear is 250,000 cycles, but it all depends on the service - ambient temperature, fluid temp, vibration, etc.

Thank you, for your answer.

The solenoid valve is used for cover gas system which supplied to welding torch (GMAW). This is automatic welding for welding special containers. There is preventative maintenance program at my company that requires replacement for these solenoids every year. The maintain group claims that it should be changed every 5 year. As an engineer I need to provide justification for this change. Since, I am junior engineer:), wanted to ask experts what will be good time frame for replacement of these solenoids.

Could you please explain more about more life expectancy in terms of cycles?

Thank you.