Help with High Flow 2" Metal Valve

[ajeagle6921]

Hi, was wondering if someone could help a person new to the valve world. I have been researching for the past 3 weeks trying to find a valve to fit my application without any luck.

I am needing a valve that is 1.5" or 2" and is made of any type of metal, just not plastic. I need it to be air operated, no electric. It needs to be very high flow atleast 45+ CV and release in under 30 ms. I have looked at dust collector valves but need a valve that is in-line not a right angle.

Any help would be GREATLY appreciate. Thanks in advance for the help.

 

[MikeHalloran]

Mechanical things generally don't move far in 30ms unless explosives are involved.



Mike Halloran
Pembroke Pines, FL, USA

 

[bcd]

Explosive bolt holding back a spring could be used to fast close a valve. So Mike is dead-on, explosives are necessary. Lots of questions to determine if design and testing effort is worthwhile. First the commercial side. How many are needed and how much are you willing to pay for each?

Then what media and pressure is in the pipe? What type of end connection. How tight does the valve have to seal after it slams shut? What happens to the valve after it shuts? Reopen and reset? Throw it out and replace it? What is it being used for? Important to know so the supplier knows their level of risk in case a valve does not shut or shut fast enough.

 

[DLite30]

a small 2" valve in this catalogue has a CV value of about 50 or so.

You're going to have more issues in finding an actuator that can move a valve fast.

http://www.velan.com/velan/en/resources/literature/download?id=62

 

[ajeagle6921]

http://www.ascovalve.com/Common/PDFFiles/Product/DC_MainPulseR1.pdf

I was thinking maybe a valve like this would work. The 1.5" has CV of 50 and would open extremely quick I think if air piloted. Not sure if 20ms or not.

The media is compressed air fyi, up to around 100-150psi. Need to exhaust about 2.5 liters of air as quick as possible. Will be threading this pipe into 3" aluminum pipes.

 

[DLite30]

Looks like it's worth a try.

 

[NGiLuzzu]

ajeagle6921,
I do apologize in advance for the stupid question, but... are You sure You actually need to open in 20÷30 ms (and not 200÷300 ms, for instance)?
How about instantaneous transient fluid velocities, chocked flow phoenomena, dynamic effects, etc...?
;-)

Hope this helps, 'NGL
_________________________________

 

[MikeHalloran]

Let me put the timing in perspective.
A while ago, I used a size 23 stepping motor with a fairly strong drive circuit to cause a valve to rotate 90 degrees in 50 ms. The valve was a Hamilton liquid chromatography teflon plug valve with a clear orifice of .080" or so; quite a small little valve.
You could hear the valve change state, but it was difficult to watch; it was just in one position, then it was in the other position. The movement was not instantaneous, but 50 ms is very rapid by mechanical standards.





Mike Halloran
Pembroke Pines, FL, USA

 

[gerhardl]

As indicated by others above, you might need to re-analyze and perhaps modify your wishes if you want to find existing commercial products.

I observe that you have had a look at dust filter valves, designed to give air shocks to rinse collecting filterbags.

Not a bad idea, as theese will have large Cv's and be some of the most fast acting types of valves on the market, but as you point out: angle-type valves. Theese valves are often based on say 0,4 to 8 bars air process media, and operated by springs/normal pneumatic air (6-10 bar) released by solenoid valves (mechanical release should be no problem)

I have not checked (or remember) the opening time for dust valves. For regular solenoid valves 30 milliseconds might be obtained by some smaller direct-acting solenoid valves, but not in the size you demand, and you stated 'no electric'.

One company specializing in dust valves (angle type) but also air/spring operated valves (will probably be lower in Cv than required) and some specialized valves not shown in published data-sheets, as well as 2/2 solenoid valves is the Norgren company:

http://www.buschjost.com/

or you could try ASCO or others:

http://www.ascovalve.com/applications/products/SolenoidDustData.aspx

You need of course data as P1, P2, media (all details), temperature media and surroundings, max operational pressure as well as minimum, how often you want to operate (sequence and number of operations, hour, day, week and year), required lifetime and operational time without service, release type (hand or mechanical?), time of operation (exclusive/inclusive response, signal and mechanical delay?), available space for mounting, connection types, ex protection/class?, and possibly other, including a more detailed verbal performance and function description of your intergrated system.

I also found this, technical datasheets giving all details, except closing time!

http://www.rizzio.it/prod_quick.html

PS. Needing a 30millisecond closing or shorter is normally required in firefighting or explosion preventing systems

http://www.fike.com/products/episolation.html

Good luck!