MTR300 Exam 3
How is the pattern that determines the geometry of the casting in expendable mold processes usually made? a. undersized b. oversized c. same size
Oversize
in casting, a flask is which one of the following? a. box which holds the cope and drag b. container for holding liquid metal c. a container to hold a beverage
a box which holds the cope and drag
in casting processes, a runner is which one of the following? a. a channel in the mold leading from the downsprue to the mold cavity b. ventilation holes to help trapped air escape the mold cavity c. cavity which holds extra molten to help mitigate shrinkage
a channel in the mold leading from the downsprue to the mold cavity
which of the following terms is used to describe the degree to which the measured value agrees with the true value of the quantity of interest? a. accuracy b. precision c. repeatability
accuracy
the empirical that determines total solidification time in casting is know as which of the following? a. chivorinos rule b. hookes law c. flow curve
chirvorions law
solidification shrinkage in casting is defined as which one of the following? a. contraction during the phase change from liquid to solid b. contraction during the phase change from solid to liquid c. liquid contraction during cooling prior to solidification
contraction during the phase change from liquid to solid
a ring gage is used to check which one of the following? a. part lengths b. tapered holes c. cylindrical diameters
cylindrical diameters
which one of the following devices is most commonly used in measuring runout? a. dial indicator b. caliper c. micro meter
dial indicator
the lower half of a sand-casting mold is called which one of the following? a. cope b. drag c. flask d. riser
drag
what is the most accurate way to measure surface roughness? a. electronic stylus instruments b. fingernail test c. surface finish block
electronic stylus instruments
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 used to hold together the sand mold (c) it increases erosion of the mold surface (d) it increases the formation of metallic oxides that can become entrapped during solidification (e) it increases the mold filling time (f) it increases total solidification time?
it dissolves the binder used to hold together the sand mold
an outside micrometer is appropriate for measuring which of the following. a. hole diameter b. shaft diameter c. roundness
shaft diameter
in inspection, which procedure provides more information? a. gauging b. measurement c. they are the same
measurement
During solidification of an alloy when a mixture of solid and liquid metals metals is present, the solid liquid mixture is referred to as which one of the following? a. solidus b. mushy zone c. liquidus
mushy zone
what is the purpose of the core in the metal casting process? a. to define the internal geometry of the casting b. to promote faster cooling rate c. to promote slower cooling rate
to define the internal geometry of the casting
a tolerance is which one of the following a. total permissible variation from a specified dimension b. clearance between a shaft and mating hole c. measurement error
total permissible variation from a specified dimension
which of the following terms is used to describe the degree of repeatability in the measurement process? a. accuracy b. precision c. repeatability
precision
a factory that performs casting processes is called which of the following? a. foundry b. molding plant c. metal working plant
foundry
in a sand- casting mold, the V/A ratio of the riser should be? a. equal to than the V/A ratio of the casting itself b. greater than the V/A ratio of the casting itself c. smaller than the V/A ratio of the casting itself
greater than the V/A ratio of the casting itself
which one of the following manufacturing processes is likely to result in the best surface finish? a. sawing b. machining c. grinding
grinding
what is the name of the sand-casting defect which occurs due to metal splatter during the pouring process? a. cold shot b. sand blow c. misrun
sand blow
what is the most widely used casting process? a. sand casting b. die casting c. plaster casting
sand casting
which of the following manufacturing processes is likely to result to result in the worst surface finish? a. grinding b. sand casting c. machining
sand casting
which of the following is not true about permanent mold processes? a. their geometries are limited by the need to open the mold b. the mold is made from a durable material and can be reused c. they have more rapid solidification which results in a finer grain structure and stronger parts
their geometries are limited by the need to open the mold
heating a metal from room temperature to pouring temperature in a casting operation depends on all of the following properties except which one? a. thermal expansion b. heat fusion c. specific heat
thermal expansion
when a tolerance is specified in only one direction from the nominal dimension, it is called a. bilateral tolerance b. unilateral tolerance c. limit tolerance
unilateral tolerance