Given that the performance curve for a particular vacuum pump is essentially flat, how can one know what the airflow (capacity) is for a given vacuum gauge reading? In this case, there is no air flow instrument that would provide that info. I'm inclined to think that a system curve will have...
I estimate velocity at about 8 ft/sec. I don't think that is excessive.
You mention a V-port above (Note 2). Remember this is not a throttling application. It merely diverts flow 90 deg from the straight through flow pattern.
The idea of two 2-way valves is good but is somewhat problematic...
It's in a location where space is very limited as there is other piping and equipment nearby. I'm going to go with another 3-way ball valve with a different seat material that will hopefully address the seat wear issue we're having.
The TFE seats on the existing 3-way ball valve are not...
Mike,
The specific gravity is 1.15. The formula I used was Q = Cv*sqrt((psid/SG)).
I got the following:
ball valve = 0.209 psi
plug valve = 5.5 psi
That represents about 11 ft head to be added to the pump discharge. From the performance curve the resultant flow would be about 300 gpm...
I have an application where a 4" 3-way ball valve has a Cv of 840 in the 'through' position. Knowing that 3-way plug valves are notoriously poor when it comes to Cv, I found that the 4" plug valve has a value of 160.
Since we're having issues with the ball valve I wanted to compare what the...
