Hello Everyone

I was wondering if anyone could provide some information on the working of the SOV in the attachment. Normally for a typical 3 Way SOV you have 3 ports i.e. Pressure, Cylinder and Exhaust. Instrument air is being routed to the pressure port and once SOV is energized the air is then routed to a valve via cylinder port. Exhaust port comes into play when the SOV is de-energized and the air is dumped through the exhaust port. I am getting confused with this pilot operated SOV below. i am trying to understand the working of this model and specifically the function of the "AUX" port on this valve.

any help would be greatly appreciated.

Thank You

 

You'll have to read through the manufacturers detailed description, before you asume how you might think it work.

 

@zuhaib,

Most (but not all) manufacturers of almost all kinds of equipment have websites that have the data sheets and installation instructions and manuals for their equipment. It seems you have at least the exterior outline; do you not have the manuals and installation instructions? Have you checked the manufacturer's site for the information? Is there a local manuracturer's representative/vendor in your area/region for ASCO valves?

 

Thanks for the response. This model is a custom made model and i havent had any success in getting info onsite and from the vendor as well. The vendor simply told me that they cant provide any info on this, not even drawings because of the custom model. I was only able to track the model from the field and then looked at the installation detail. But no luck so far in finding any manual.

 

You'll have to read through the manufacturers detailed description, before you asume how you might think it work.

Only if i can find that manual from the manufacturer. This being a custom model, vendor has not been able to help at all.

 

@zuhaib,

We don’t know where you found the attachment AND we don’t know what application the valve is being used for. It would also be helpful if you could provide a P&ID (Piping & Instrumentation Diagram) of the system the valve is installed in. It would be really useful also if you could provide the nameplate information from the valve itself.

Also we don’t know what kind of problem you perceive to be related to the valve. We don’t know if the system worked properly for some time and just recently started giving problems or … what. We don’t know if the voltage to the device has been verified.

Unless I’m missing something I don’t see any ports with labels on the attachment you provided.

Without some idea of the system the valve is used in and how it’s connected to the system it’s really difficult to say anything with any degree of certainty about the valve. I have seen some ASCO assemblies that were custom-built using standard ASCO devices. And those were pretty self-explanatory after looking at the P&ID for the system. And for those that weren’t self-explanatory it was sometimes required to ask the manufacturer of the equipment the device was provided with for assistance.

I find many times that pneumatic devices fail when the air supply is not correct. Most pneumatic control devices require clean, dry instrument air, sometimes even at a lower pressure than the instrument air system provides, requiring a pressure regulator in the air supply to the device and the pressure regulator is dirty or plugged or broken or misadjusted. Sometimes the pressure regulator has a glass “cylinder” to trap moisture and it requires manual operation to drain the water from the cylinder.

But without knowing more about the application and the symptoms/problems being experienced and the troubleshooting that’s been done and what the results of the troubleshooting were we can’t provide much more information.

 

Thanks for the response. the model # that i got from the field is HV-276890-2. Due to confidentiality of the drawings i want be able to post them here but i can for sure tell you that we are using this model of SOV on an existing fuel gas control valve in order to make it act like a chopper or on/off valve. we already have one chopper valve on the fuel gas line and we dont want to add another one due to piping modifications and cost. That said we will use the control valve as a second chopper.

The standard that we have dictates that any time we have a trip, the SOV has to "LATCH" and hence this mode is used everywhere onsite due to latching/manual reset. That is one of the reasons for going with this model but "AUX" port on this model of SOV is not making sense to me.

I hope this gives you additional info. Thanks once again for your reply.

 

Without more technical drawing information, there's not much more anyone--except someone who has worked with this specific valve, which apparently isn't like the existing "chopper valve" (which most of the world calls a fuel shut-off valve...)--can offer. And that might be hard if it's a custom application of which there aren't many in use.

I suggest you look at the ASCO website for similar valves with an AUX port to understand how it is intended to be used.

Also, are you certain the existing fuel shut-off valve doesn't have an AUX port that may just be plugged or blanked off?

AND, again, if you have a working relationship with a local company that sells and represents ASCO valves you should try contacting them for more assistance. If you're trying to use a spare custom valve purchased from the packager of the original fuel shut-off valve and it's NOT the same as the one already in service at your site, you should be contacting the seller of the valve (the packager of the fuel shut-off valve) and asking for clarification of how to install the valve with an AUX port the original valve does not have. If they sold it to you and it's NOT the same as the existing valve then they should recognize an obligation to provide proper installation instructions.

There's just something fishy about this....

Best of luck!

 

I want to add, that typically fuel shut-off valves and fuel control valves have very different sealing ratings, and many regions of the world have very specific technical regulations and/or standards regarding fuel shut-off valves. Having said that, I worked on machines that used fuel control valves as shut-off valves--but their leakage rates when closed met most of the technical regulations and standards in most of the world. But, as those machines grew bigger and bigger they were forced to add a true fuel shut-off (on-off) valve upstream of the fuel control valve.

We don't know if instrument air is the gas used in the fuel shut-off valve actuator/operator, or if it's pilot-operated using fuel gas. (That may be part of the proprietary nature of the solenoid-operated valve in question.) Again, part of the situation we don't know and which has to be worked out on site.

You could also ask ASCO or another solenoid-operated valve manufacturer what they would recommend by providing them with the requirements of the application/system and see what they propose to meet your needs.... Could be very informative. VERY informative.