Question

10.1 Investment casting is more suitable for mass production compare to sand casting: (a)True (b) False (0.1mark) Answer 10.2 Total solidification time is defined as which one of the following: (a) time between pouring and complete solidification, (b) time between pouring and cooling to room temperature, (c) time between solidification and cooling to room temperature, or (d) time to give up the heat of fusion? (0.1mark) Answer. 10.3 A riser in casting is described by which of the following (three correct answers): (a) an insert in the casting that inhibits buoyancy of the core, (b) gating system in which the sprue feeds directly into the cavity, (c) metal that is not part of the casting, (d) source of molten metal to feed the casting and compensate for shrinkage during solidification, and (e) waste metal that is usually recycled? (0.1mark) Answer. 10.4 Sand casting is which of the following types: (a) expendable mold or (b) permanent mold? (0.1mark) Answer. 10.5 In foundry work, a runner is which one of the following: (a) channel in the mold leading from the downsprue to the main mold cavity, (b) foundryman who moves the molten metal to the mold, or (c) vertical channel into which molten metal is poured into the mold? (0.1mark) Answer. 10.6 In a sand casting mold, the VIA ratio of the riser should be (a) equal to, (b) greater than, or (c) smaller than the VIA ratio of the casting itself? (0.1mark) Answer. 10.7 The upper half of a sand casting mold is called which of the following: (a) cope or (b) drag? (0.1mark) Answer 10.8 Chvorinov's Rule states that total solidification time is proportional to which one of the following quantities: o)(aiv), (b) H, (c) T, (d v,(e) VIA, or (0 (VIA); where A-surface area of casting, H-heat of fusio 7- melting temperatur,and y- volume of easting? (0.1mark) Answer.

Answer 1

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