Design and Analysis of Marine Crane for a Container Ship

Module Learning Outcomes (MLOs) Assessed by Coursework

MLO1 Apply advanced knowledge, scientific and mathematical principles to model a mechanical system.

MLO2 Critically apply and integrate knowledge and further understanding of other engineering disciplines to study of mechanical systems.

MLO3 Utilise critical advanced quantitative methods and computer software in the analysis of components under complex static and dynamic loading conditions.

MLO4 Solve problems to the benefit of society by applying good engineering practise.

Coursework Overview

As a mechanical engineerer in a naval architecture company, you are asked to design a marine crane for a container ship and write a design report to the project manager. The heaviest container for the crane to lift is 80000 kg. Moreover, due to the impact of sea swell on the ship, the dynamic amplitude factor (DAF) of 5 is considered. The dimension requirement of the crane structure is given in the figure below. The whole structure is composed of four steel members connected to each other by pins. The density, Young’s
modulus and yielding stress of steel are respectively: ? = 7860 kg/m3 , E = 200 GPa, ?Y = 250 MPa.

You need to determine the size and cross section of each member to avoid buckling failure and yielding. Moreover, you need to reduce the product cost by using as few materials as possible, i.e., the lightest crane. You also need to maintain the rigiditiy of the structure, i.e., the smallest displacement of the holding point B.

 

                                                                                                 

Coursework Tasks to be Completed by Students

Propose 3 ~ 5 designs of marine crane: layout, size, and cross section of each member.

 

CAD software drawing is preferred. Hand drawing is also acceptable, but you need to ensure the quality and clarity of your hand drawing.

                                                                                           

 

Perform finite element analysis (FEA) to find the axial stress and displacement of each design (refer to:

Seminar 3. Truss bridge modelling).

Perform buckling analysis of each design to check whether the design will have buckling failure or not (refer to: Lecture 4. Buckling – slides 17~22). Discuss the improvement if the design fails.

 

Note: buckling analysis only for the members under axial compressive force.

You can consider FoS (factor of safety) or not in the buckling analysis. If you want to consider FoS, you can choose a value by yourself.

 

For buckling calculation, typing is preferred. Hand writing is also acceptable, but you need to ensure the quality and clarity of your hand writing.

Perform yielding analysis of each design to check whether the design will have yielding failure or not (refer to: Lecture 5. Nonlinear behaviours – slides 12~14). Discuss the improvement if the design fails.

Note: yielding analysis only for the members under axial tensile force.

 

You can consider FoS (factor of safety) or not in the yielding analysis. If you want to consider FoS, you can choose a value by yourself.

 

For yielding calculation, typing is preferred. Hand writing is also acceptable, but you need to ensure the quality and clarity of your hand writing.

• Compare proposed designs by weight, rigidity, buckling and yielding failures.
• Choose the best design and discuss how your design considerations and solutions are beneficial to the society.