New design of Butterfly valve

[espresso51]

Hi to all. I have designed. patented and am now manufacturing a new kind of butterfly valve. The design was geared towards a plastic valve that would be used on an outlet to a storage tank, where the pressure would always be in one direction only, and the valve had to be leak free for long periods of time. A further criteria was that the spindle seal shouldn't be under pressure - i.e. the spindle had to be on the outlet side of the valve. The resulting geometry caused a standard butterfly valve to be self opening due to the pressure imbalance on the disk. My design has overcome this and in fact I have a valve that is now self closing. The design is such that the valve could be self closing or neutral.
My question is - do any of you guys think that such a valve might be useful in any other field? I would imagine that a valve with this design could be used for high pressure applications where the actuating forces wouls normally be very high, or for very big dia valves, where the actuation forces would also be large. A valve used in a dam perhaps (the self closing feature?)

 

[JLSeagull]

My group doesn't buy dam valves. We buy valves that comply with several industry standards including API, ASME and MSS. To sell to the oil, gas and petrochemical industries assure that your design comlies with ASME B16.34. MSS SP-67A and 68 are among butterfly valve standards. Examples include API Specifications 6D, 6FA, 6FB, 6FC, standard 598, 607, 609 (as I require lugged butterfly valves in hydrocarbon service), etc. OK, throw in some ISA standards too.

 

[NGiLuzzu]

espresso51,
I'm afraid I didn't get all the meaning of your post...

May I ask what are the analogies and differences between your new valve design and existing ones (simmetric butterflies, HPBVs, triple-offset and "clapet" check valves)?

Am I right if I understand that is a valve made of plastic material? In that case, if I remember well, ASME B16.34 is not applicable (more specific standards should be retrieved...).


Thank you in advance, 'NGL

 

[espresso51]

Hi,
First of all I am not hoping to sell my plastic valve to anyone other than my existing customers.
I have patented a design of double offset valve that if it is receiving pressure from the non spindle side, it is then self closing or neutral in terms of the forces on the disk. All I want to know is whether there may be any application for such a concept in other industries besides the one that I am making for.

 

[JimCasey]

I am curious as to what the patented features are. Traditional double-offset butterfly valves are self-closing due to dynamic torque, with the torque peak occurring at about 75 degrees open. With the shaft upstream, they would be self-closing at the seat due to the moment generated by the pressure against the back of the disc and the stem offset. The favored flow direction for a double offset butterfly is with the shaft downstream and the disc /seat upstream, but this is mostly to take the pressure off the packing while the valve is closed.

 

[espresso51]

Hi Jim,
Exactly as you put it. If you want a double offset butterfly valve with the shaft DOWNSTREAM then the traditional valve would be self opening. This fact is exactly what I have overcome, but it only applies if you want the configuration of shaft downstream. This would apply if you want to take the pressure off the shaft packing. I wanted to do this simply to remove one of the possible leakage sites.

 

[Ashereng]

espresso51,

As JL mentioned, in the oil and gas industries, plastic would most likely not be allowed. I have never bought anything in plastic.

Perhaps in water treatment service (I don't have much experience there), or fire water (I don't have much experience there either)?

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