Between Globe,Ball,and Gate, which type of valve is capable of maintaning Differential Pressure better?

You can get some pressure differential at nearly closed positions with the other valve types, but too close to fully closed to do you much good.  They will also be subject to erosion and filling the seal areas with dirt when in that position.  It's by far better to use those types of valves in Open or Closed Positions only.  Some patterns of plug valves and butterfly valves would be more effective for throttling, if for some reason you don't want to use a globe type.

For on/off "control", an actuated ball valve gives more predictable results than the globe valves with diaphram operators that are often used for dump valves or wellsite ESD valves.  I've done the accident investigation on at least 3 fires that the root cause was a diaphragm operated globe valve in on/off service (as a spec break) that leaked through and over pressured downstream equipment.  This is common practice in Oil & Gas, and it is a bad practice.

It's best not to assume that an orifice will make the downstream segment more safe.  An orifice contributes only pressure drop when fluid is flowing through it at a relatively high rate and has no effect on the absolute values of either the upstream or downstream pressures.    The pressures in either the up or downstream segments are a function of your boundary and control conditions at the inlet or the outlet respectively and have nothing to do with the orifice plate's, or pipe pressure drops in between.  Inlet pressure - pressure drops = outlet pressure; Outlet pressure + pressure drops = Inlet pressure.  You can see that you must have one pressure known (your boundary condition) either at the inlet or at the outlet, and you must know the flow to calculate all the pressure drops in between.  An increased pressure drop from the orifice will either reduce the downstream pressure  only when the upstream pressure is controlled constant.  Likewise an increased pressure drop will raise the upstream pressure only when the downstream pressure is controlled constant.  If neither is controlled, an increased pressure drop might raise one and lower the other, but might not.  An orifice plate will do nothing to stop a slow buildup of pressure (from changing boundary conditions) when there is negligable flow in the line.

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