36" Wafer Butterfly Valve: Through Bolt Holes Nearest to Stem 1

[lazzydogg]

I was wondering if any you have seen any 36" Wafer Butterfly Valve 150# with through bolts holes (guide holes) for connecting the mating flanges instead of taps which are nearest to the stem.
Thanks.

 

[bcd]

Even with a reduced pressure rating (i.e., valve can't withstand the full Class pressure rating across the disc when the valve is shut), the spacing between the bolts is smaller than normal shaft diameters. In order to get the required wall thickness per ASME B16.34, you need to drill and tap the flange holes near the shaft. If you drill through, you will break into the shaft bore and even cut into the shaft.

In short, no through holes.