Difficult to advise as it looks like the attached print is incomplete. regardless, I would attempt to revolve as much as possible based on the section views provided, starting with D-D. Then add an extrusion based off section C-C for the upper part of the form. Then another revolve for the top/center port based on the vertical axis of D-D. Add relief cuts as needed. Shouldnt need to do much lofting/guess work if adequate views/dimensions are provided.
I would model the valve as if it didn't have internal passages.
Then I'd separately model the interior as its own part.
Then I'd locate the interior inside the valve (aligned to common planes) and combine>subtract.
This way you can concentrate on one and get it right. Then the other. And when both are good, then combine.
For the interior, I'd leave off these nubs from the interior model and add one after the combine, then mirror it to the other side.