Unit Learning Outcomes LO2 Determine parameters within mechanical engineering systems. Assignment Brief and Guidance Scenario: You are the Maintenance Manager of a large galvanising company in Telford. At the weekly management meeting, the Managing Director and Finance Director have raised concerns and asked you to deal with the following maintenance issues before next week's meeting. 1. Gantry crane breakdown The travelling gantry crane has broken down. To affect a repair, one of the supporting legs has to be lifted. Can this be handled in house, or is specialist lifting gear required? A diagram of the crane and the distribution of its weight is shown below. a. Determine the reaction force carried on each leg b. You have a 1.5 tonne jack available to lift each leg - will this be sufficient and if so what safety factor does it give? 18 kN 5kN/m FIC N 3m 3m 6m Leg A 2m Leg B Whilst repairing the crane, you take the opportunity to check the condition of the wheel bearings and need to remove a cover plate to do so. After checking the bearings, you need to replace the cover plates. The cover plate is washer like in shape and made from aluminium. It has an internal diameter of 48.2mm and a thickness of 5mm (figure 2). The cap must fit onto a shaft which has a diameter of 48.3mm. Determine: C. The diameter of the aperture in the washer if its initial temperature is 21C and it is heated to 150 C, take the coefficient of linear expansion for aluminium to be 24 x 10-6 m C-1 Figure 2 d. The iron shaft, at the same initial temperature, is subject to a temperature change of 40C due to heat transfer during the fitting process - what will the shaft's final diameter be and will the washer fit? Take the coefficient of linear expansion for iron to be 9 x 10-6 m C-1 2 Cont'd overleaf