Based on my 8 years of experience in Oil & Gas industry I'm trying here to introduce you to the most of what you may need to know about Process Control as a chemical engineer. This is an introduction to understand more about :- -Final Control Element -Components - Types - Sizing Equations This is 4 of 4 presentation on this topic. All the data and the illustrative figures presented here can be found through two reference books:- ENGINEERING DATA BOOK by Gas Processors Suppliers Association Process Technology - Equipment and Systems by Charles E. Thomas VALTEK (1995) Control Valve Sizing and Selection Manual. Thank you.