Answer Happy

b) A farmer requires the assistance of an outdoor mobile lift to assist in the pruning of trees on a 40 ha estate. One option is to use a two stage displacement type telescopic hydraulic lift that is attached to the tractor and powered by the tractor's PTO. Such a design would incorporate the use of a universal joint between the tractor and hydraulic lift implement. The universal joint is a coupling device that permits rotation between two shafts. The 80 hp tractor PTO rotates at 1000 rpm. Perform the following- i. Draw a hydraulic schematic that can be used for the telescopic hydraulic lift (4 marks] ii. Determine the specifications of the hydraulic pump given that the lift raises a maximum of 300 kg at a maximum speed of 5 cm/s and the outside diameters of the cylinder tubes are 150 mm and 254 mm [4 marks] iii. The PTO shaft is attach to a universal joint and has an input torque of 580 Nm. Given that the input and output shafts are in the same horizontal plane. Determine the range of values for the output torque of the driven shaft given that joint angle (a)is equal to 0.21 rads. Assume 5% losses in friction. (4 marks] iv. Deduce if the tractor can perform the work given the power requirements of the lift. [3 marks]