thePetroStreet

Hi

It is usually seen that control valve in "control valve manifold " assembly is one size smaller than the attached pipe run. Why is it so?

Regards

as a general rule, the reduced control valve size compared with the pipe size in which it controls the flow makes it more convenient to impose stable control and produces more pressure drop thus reduced flow which is the main purpose of the control valve

however, due to certain restrictions the control valve size could very well be of the same pipe size but this would be too restrictive a constraint which needs to adequately justified if for nothing but the increased cost

Agree with Alzuhd. Adequately explained.