Few things are more irritating than a dripping tap. Taps drip because the rubber washer is worn or the brass seat is pitted by corrosion, or both. Ceramics have good wear resistance, and they have excellent corrosion resistance in both pure and salt water. Many household taps now use ceramic valves.

a. List the function and constraints, leave the objective blank and enter 'Choice of process' for the free variable.

b. Use the charts of Figs. 7.3, 7.4 and 7.6 to identify processes to shape the casing.

Data From Fig, 7.3

Data From Fig, 7.4

Data From Fig, 7.6

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