In this paper,the traditional mechanical design & manufacturing are compared with mechanical automation.The paper points out intelligent features are the essential difference in function between modern machinery and traditional machinery.Mechanical automation shows its advantages and benefits in application and development in all walks of life,such as multifunction,high efficiency,high reliability,material saving,energy saving,and it constantly meets the diverse needs of people living and production.This paper integrates mechanical technology,microelectronics,automation technology and process control technology and apply to the chemical production from the concept of system.It focuses on the optimal control scheme of boil drum water level,coolant flow and ammonia emissions,puts forward the main objective of the process automation control in the future,and points out the development direction of mechanical design & manufacturing and automation.