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11 Cards in this Set
- Front
- Back
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10.1 Sand casting is which of the following types: (a) expendable mold or (b) permanent mold? |
Answer. (a). |
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10.2 The upper half of a sand-casting mold is called which of the following: (a) cope or (b) drag? |
Answer. (a). |
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10.3 In casting, a flask is which one of the following: (a) beverage bottle for foundrymen, (b) box whichholds the cope and drag, (c) container for holding liquid metal, or (d) metal which extrudes betweenthe mold halves? |
Answer. (b). |
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10.4 In foundry work, a runner is which one of the following: (a) channel in the mold leading from thedownsprue 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? |
Answer. (a). |
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10.5 Turbulence during pouring of the molten metal is undesirable for which of the following reasons(two best answers): (a) it causes discoloration of the mold surfaces, (b) it dissolves the binder usedto hold together the sand mold, (c) it increases erosion of the mold surfaces, (d) it increases theformation of metallic oxides that can become entrapped during solidification, (e) it increases themold filling time, and (f) it increases total solidification time? |
Answer: (c) and (d). |
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10.6 Total solidification time is defined as which one of the following: (a) time between pouring andcomplete solidification, (b) time between pouring and cooling to room temperature, (c) timebetween solidification and cooling to room temperature, or (d) time to give up the heat of fusion? |
Answer. (a). |
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10.7 During solidification of an alloy when a mixture of solid and liquid metals is present, thesolid-liquid mixture is referred to as which one of the following: (a) eutectic composition, (b) ingotsegregation, (c) liquidus, (d) mushy zone, or (e) solidus? |
Answer. (d). |
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10.8 Chvorinov's rule states that total solidification time is proportional to which one of the followingquantities: (a) (A/V)n, (b) Hf, (c) Tm, (d) V, (e) V/A, or (f) (V/A)2; where A = surface area of casting,Hf = heat of fusion, Tm = melting temperature, and V = volume of casting? |
Answer. (f). |
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10.9 A riser in casting is described by which of the following (three correct answers): (a) an insert in thecasting that inhibits buoyancy of the core, (b) gating system in which the sprue feeds directly intothe cavity, (c) metal that is not part of the casting, (d) source of molten metal to feed the casting andcompensate for shrinkage during solidification, and (e) waste metal that is usually recycled? |
Answer. (c), (d), and (e). |
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10.10 In a sand-casting mold, the V/A ratio of the riser should be (a) equal to, (b) greater than, or (c)smaller than the V/A ratio of the casting itself? |
Answer. (b). |
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10.11 Which of the following riser types are completely enclosed within the sand mold and connected tothe main cavity by a channel to feed the molten metal (two correct answers): (a) blind riser, (b) openriser, (c) side riser, and (d) top riser? |
Answer. (a) and (c). |
