1. Exercise Problem No. 5 • Figure below shows a diagram of fluid power system for a hydraulic press used to extrude rubber patrs. The following data are known : • The fluid is oil (sg =0,93), Volume flow rate is 175 gal/min • Power input to the pump is 28.4 hp, Pump efficiency is 80 % • Energy loss from point 1 to 2 is 2.80 lb-ft/lb, from point 3 to 4 is 28.50 lb-ft/lb and from point 5 to 6 is 3.50 lb-ft/lb • a). Compute the power removed from the fluid by the press • b). Compute the pressure at point 3 at the pump outlet • c). Compute the pressure at point 5 at the press outlet Answer : a). 21.16 hp b). 219,1 psig c). 1.01 psig

2. Jawab :

3. b).

4. c).

5. Soal Kuis 2 Gambar di bawah ini adalah suatu bagian dari sistem pemadam kebakaran dimana pompa menarik air pada 50oFdengan debit 1500 gal/min dari suatu reservoir dan mengeluarkannya ke titik B. Kehilangan energi antara reservoir dan titik A adalah 0,65 lblb.ft/lb. a). Tentukan kedalaman h untuk mempertahankan tekanan paling sedikit 5 psig pada titik A. [12,8 ft] b). Bila titik A tekanannya 5 psig tentukan daya pompa yang diperlukan agar tekanan di B adalah 85 psig. Kehilangan energi antara pompa dan titik B adalah 28 lb.ft/lb [90 hp]

6. 1 2

9. Exercise Problem No. 6 Professor Crocker is building a cabin on a hillside and has proposed the water system shown in figure below. The distribution tank in the cabin maintain a pressure of 30 psig above the water. There is an energy loss of 15.5 lb-ft/lb in the piping. The pump is delivering 40 gal/min of water. If the pump has an efficiency of 72%, what size motor is required to drive the pump ? Answer : 42,8 hp