Assignment II (15%) 1. If the applied system pressure is 300MPa and the actuator has a bore of 250mm. Due to internal leakage, the cylinder has a volumetric efficiency of 90 percent. a. Find how much extension force can be exerted by a hydraulic cylinder b. Calculate time the cylinder takes to extend if the pump flow applied to the cylinder was 20 litres per minute and the cylinder had a 500 mm stroke. 2. If the motor displaces 130 cm3 per revolution and the flow to the motor is set at 60L/min. a) Find the speed of a hydraulic motor b) calculate flow rate in litres per minute c) Calculate the required pump input power in kilowatts (kW) for a system that has a pressure of 80MPa. Assume a volumetric efficiency of 97 per cent. 3. Calculate theoretical delivery flow Qtp and actual delivery flow Qp of a pump which has stroke displacement qp = 12cm3rev-1. The pump shaft rotation speed is Np =4800rpm and the pump volumetric efficiency ŋvp= 0:82. 4. A pump which has unit displacement qp = 230 cm3rev-1 operates under pressure p = 300bar. What is the required input torque if pump hydro-mechanical efficiency is ŋhmp = 0:98? 5. Calculate the actual delivery flow rate Qp of a pump if its unit displacement is 𝑉 ∅= 4cm3rad1 and its shaft angular speed is 𝜔p = 400 rad-1. Pump leakage loss is Qvp = 120 cm3s-1. What is the volumetric efficiency of the pump? 6. Main dimensions of gears in a gear pump are: gear width b = 25mm, number of teeth z = 16, modulus m = 5. Calculate the theoretical delivery flow Qtp when shaft speed is Np = 3000 rpm.