I need your advice regarding the valve symbol in the attached picture. I’ve come across this valve in a project but fail to identify what it actually is. Hope someone would be able to name this valve and hopefully identify some source as well. I’m fairly sure this is not a shuttle valve.
Here is a picture (albeit a fuzzy one):
I guess I would call it a fixed flow restrictor with bi-directional excess flow check valves. The check valve would close when the deltaP across the flow restriction exceeds the check valve spring force.
Above is a snippet.