A proposed laboratory scale cylindrical polymerization reactor to make high density polyethylene (HDPE) needs to be designed and constructed. The maximum design temperature and pressure of the reactor are 200 oC and 25 MPa, respectively. The reactor is used 4 times per day and must be designed for a minimum lifetime of 20 years. The inside diameter and wall thickness of the reactor are 300 mm and 10 mm, respectively. To meet safety regulations, a safety valve will be installed if the pressure exceeds 22 MPa, which will cause a maximum