Question

Square soda bottle is proposed to replace the traditional cylindrical shape. Both have the same height for packaging and storing purpose.

*Use HDPE plastics for both shapes

*Bottle cross section: 4 inch square or 4 inch diameter, 0.050 inch thick

*Blowing pressure: varies

*Assume tensile strength of HDPE is 20% lower than that at room temperature

a) Find the blowing pressure that bursts each container at molding temperature of 170 F

b)Which is cheaper to produce? Why?

Answer 1