Posted: January 4th, 2017

Consider a cylindrical pressure vessel that is used for chemical processing in which the full pressure is limited to 22.5 MN m–2

.On a sketch of a cylindrical pressure vessel subjected to an internal pressure P, illustrate in which orientation a crack like defect would be most likely to cause failure when the internal pressure reaches a critical value. (6 marks)  b.Consider a cylindrical pressure vessel that is used for chemical processing in which the full pressure is limited to 22.5 MN m–2. The vessel has a mean radius of 2.8 m and a wall thickness of 0.16 m, and is constructed from welded plates of material with UTS 625 MN m–2 and a yield strength of 465 MN m–2. o i.Calculate the maximum stress at full pressure that could drive the growth of a crack. o ii.State, with justification, whether or not the service condition represents a high load on the structure. o iii.Following fracture toughness testing on this material it is established that the fracture toughness is 95 MN m–3/2. Use the Mathcad R6 Calculator to determine the safety factor for a flaw that penetrates 2 mm into the wall section (i.e. a ‘crack length’ of 2 mm on the Mathcad R6 Calculator) with zero secondary stress. State what type of failure is likely to occur if the vessel is overloaded. o iv.Discuss whether the safety factor determined in (iii) is acceptable. (4 + 4 + 10 + 4 = 22 marks)  c.The vessel is welded, so conservative procedures demand that you assume that any flaws are in the weld zone. During welding a residual (secondary) stress of 180 MN m–2 is introduced into the pressure vessel. Using the R6 calculator, determine the maximum internal pressure the vessel can withstand without failing when it contains a 7.5 mm crack. (12 marks) (Total 40 marks) Question 2 Question 2 Question 2 This question carries 12% of the marks for this assignment. Your answer should be no more than about 400 words  a.Look at the photograph of a cyclist in Figure 1. Using the definitions given in Block 3 part 1, give an example of different parts of the cyclist and/or bike displaying. o i.rectilinear motion o ii.circular motion o iii.curvilinear motion