1. Mechanical Design of Process Equipment

4. 13.1. INTRODUCTION Mechanical design of chemical plant
particular interest to chemical engineers
developing and specifying the basic design information
will be responsible for
Mechanical design of chemical plant
pressure vessels
storage tanks
heat-exchanger
Vessel function.
Process materials and services.
Operating and design temperature and pressure.
Materials of construction.
Vessel dimensions and orientation.
Type of vessel heads to be used.
Openings and connections required.
Specification of heating and cooling jackets or coils.
Type of agitator.
Specification of internal fittings.
data sheet for pressure vessel design

5. 13.1.1. Classification of pressure vessels
Pressure vessels are sub-divided into two classes depending on the ratio of the wall thickness to vessel diameter: thin-walled vessels, with a thickness ratio of less than 1 : 10; and thick-walled vessels, above this ratio
If the wall is thin, the radial stress 3 will be small and can be neglected in comparison with the other stresses, and the longitudinal and circumferential stresses 1 and 2 can be taken as constant over the wall thickness.
In a thick wall, the magnitude of the radial stress will be significant, and the circumferential stress will vary across the wall.

6. Piping & Instrumentation Diagram

7. Data sheet for pressure vessel design
Sufficient for the chemical engineer
to check the feasibility of a proposed equipment design
to estimate the vessel cost for an economic analysis
to determine the vessel’s general proportions and weight for plant layout purposes

14. 13.2. PRESSURE VESSEL CODES AND STANDARDS
British Standard PD 5500
European Standard EN 13445
American Society of Mechanical Engineers code Section VIII (the ASME code)
Design
materials of construction
fabrication (manufacture and workmanship)
inspection and testing
The current (2003) edition of PD 5500 covers vessels fabricated in carbon and alloy steels, and aluminium
The design of vessels constructed from reinforced plastics is covered by BS 4994
The ASME code covers steels, non-ferrous metals, and fibre- reinforced plastics

15. TERIMA KASIH