How would you call such a valve? 2

[nouanda]

Dear all,

I need your experience for a very small problem...
How do you call a ball valve whose passage is smaller at the outlet than it is at the inlet? (see the attached drawing)

Thanx
Nouanda

 

[Garlik]

Reduced ball valve.

 

[Garlik]

Reduced ball valve

 

[Unotec]

Reduced port ball valve

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying ” Damn that was fun!” - Unknown>>

 

[gerhardl]

Either reduced bore ball valve or somewhat false sketch of V-port ball valve.

I am a bit unsure about your sketch. Normally the cone reduction described is in the housing, while the reduced boring is even or symmetrical through the ball, or somewhat rounded equally on both sides of the ball itself.

See link and explanation.

http://www.summitcontrols.com/FAQ/FAQ.html

What is a full bore valve?

A full bore (or full port) valve is one where the hole in the ball is equal in diameter to the hole in the pipe. In other words, if you were to look down a piece of pipe which also contained the valve, you would not notice any constriction at the location of the valve.


2. What is a reduced bore valve?

A reduced bore ( also called a standard bore or port) valve is one where the hole through the ball is smaller than the hole in the pipe. In some valves such as the Jamesbury 5000 series, there is a gradual narrowing so that the valve almost looks like a vena contracta. In other valves, such as the reduced bore Jamesbury 4000 series, the reduction is simply a shoulder.

Often, the reduction in diameter is to the next standard size. For example, a 2" (nominal size) reduced bore valve would have a 1.5" bore in the ball. A 1.5" (nominal size) reduced bore valve would have a 1.25" bore in the ball and so on. This comes from a rule of thumb which actually coined the term "standard bore" as much as the desire for modular design to allow the same ball to be used in one size of full bore valve and another of a standard bore. Long time ago, the engineers noticed that to get good control, very often the solution was to use a full bore valve of one size smaller than the pipe you were using. Now, this arrangement required reducers on either end of the valve. Someone then came up with the idea of integrating the reducers in to the valve and the standard bore valve was born.

.....

A V-port ball valve has a V-opening in a shell-formed ball section. Controlling the flow from fully closed to reveling more and more from narrow end tu full V to regulate a flow.

 

[nouanda]

Thank you all for your attention.

Gerhardl: the cone is actually inside the ball. This valve is used on a circuit that may be subject to plugging.
When the valve is plugged (due to the cone), the operator rotates the valve at 180°, then the dirt can be easily removed.
that's why I posted my question. I knew the definition of full bore and reduced bore, and also the fact the the ball is usually symmetrical (at least, for what I've seen), but I was curious about this particular configuration.

 

[roydm]

That's interesting, so the operator rotates the valve 180° and the plug blows off down the line?
Wouldn't be lime by any chance? Air activated pinch valves work well in that application.
Roy

 

[gerhardl]

I am also curious! I still don't see the reason for the configuration (constriction within the ball). Im my mind any constriction in a pipeline that tend to clog, will increase the clogging tendency at that particular point.

 

[nouanda]

I am not sure either... to be honest, I posted here, because a colleague was searching for a translation (we're French), but even in French, we don't know how to call this (and everybody knows we are good at creating complicated words for technical applications!)
The only thing we can imagine is that the valve is used to create a high deltaP, but compared to a restriction orifice that would be more usual, it is easily cleanable (by turning 180°).

 

[Unotec]

Could it be some sort of pressure control valve?

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying ” Damn that was fun!” - Unknown>>

 

[belowzero]

We made a very similar item many years ago in NJ from a solid ball. However it was not actually given a name as it was the customer themselves who provided the sketch.
The stops were changed to allow the ball to rotate 180 degrees. As far as we were concerned it was a very crude manual control valve for setting a specific Dp which was then left set.
B

 

[unclesyd]

During the eighties we had a pilot plant that used a number of similar valves with the exception that the hole through the ball were mostly straight holes with a few conical holes thrown in. They were on a manifold to change the flow rates of several streams going into a reactor without a lot of high dollar control valves and instrumentation.

These were called "Orifice Valves".

 

[gerhardl]

belowzero, unclesyd --- thank you for enlightening input, but out of curiosity, why the special make?

Could not a standard V-port ball valve have given the same effect? Or where there present any special considerations?

(price? pressure or temperature range?)

 

[unclesyd]

I think it depends on what period of time you are talking about as the V-port valve was a late comer. It also stay with the larger sizes for good period of time. It was a long period when you could only get the quarter turn ball valve in one flavor, that is round with a circular hole. The non-circular bore valves were slow to show up and even slower to catch on. If you look at the history of the ball valve it is fairly new arrival and really didn't catch on until the Teflon seat was perfected.

Improvements and design changes also came slow. How many stems were put in orbit and feet got burnt from accidentally opening the lever operated valve before things started to change.

When we made and used the ball valve as an on/off orifice we had to get the balls from an outside source as the valve manufacturer wouldn't sell us a ball without a hole.

 

[belowzero]

unclesyd is mostly right, the other point is that the vee port was either a metal seat with the formed aperture and the use of a standard ball, or a solid ball machined with a parallel cutter forming the 'Vee', the Vee that is talked about here and the ones we made have a tapered Vee, this reduces any debris hang up at the beginning of the balls transition in shape. The edges of the Vee foem were also radiused slightly.
The other reason for what we classed as a 'special' was the shear low quantity/demand for this valve.
B