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Politecnico di Milano MANUFACTURING SYSTEMS ENGINEERING GENERAL RECOMMENDATIONS  During the exam, ONLY the official lesson material and the suggested additional material are allowed  Exercise material, solved exercises or personal notes are NOT allowed.  Write using a pen; pencil written texts will not be considered.  The written text is the only official document which will determine the final mark o Report all your hypotheses o Report the used formulae, the complete procedure and the numerical results o Report all the graphs on your exam paper sheets EXERCISE The TecnoMilano S.r.l. is a supplier in the automotive market. Its plant is divided into various manufacturing cells, each of them composed by automated machining centers. One of these cells is dedicated to process t hree part types (A, B, C). The demand of these part types is known for the next year and is equal to 6000, 8000 and 10000 [ part/year] respectively. In the manufacturing cell there are 3 identical 3 -axis machining centers (Type1) with a spindle speed of 8000 [RPM]; the three parts can be machined on this type of machine with a total machining time of 2160, 2880 and 2520 [s/part] respectively. The plant is open 230 days in a year with 3 shifts of 7 hours each. The availability of the Type1 machining center is 0.93. The firm is discussing with a client about the supply of a new part type (D). It is estimated that there is a 60% probability to sign the contract; in this case, 12000 parts must be produced during the next year. The new part type (D) is more complex than the other ones and two setups are necessary to machine it on the Type1 with a total time of 3240 [s/part]. It is also possible to purchase a 4 -axis machine (Type2) with a spindle speed of 12000 [RPM]; since the Type2 has a higher…