Casting MCQ
Best process for small nonferrous casting with thin sections
Die casting
A flask is
Box which holds cope and drag
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?
C, D, E
Metals typically used in die casting
Cast iron, tin and zinc
Permanent mold operations casting
Centrifugal and die casting
In foundry work a runner is
Channel in the mold leading from the down sprue to the main mold cavity
The main function of the down sprue is to eliminate the cold shut defect in the product
False
Not advantages of die casting over sand
Higher melting temperature metals and larger parts can be cast
Properties which make a material more suitable for sand casting
Low melting point and high fluidity
Material suitable for making die casting products
Metals that can melt at low temperatures
Why is green mold called that
Moisture is contained in the mold
Material suitable for lost foam casting
Polystyrene
Super heat is the temperature difference between
Pouring temperature and melting point
Liquid is a temperature at which an alloy
Starts to freeze Melts completely
Cooling curve of pure metal shows a relationship between
Temperature-time
In sand casting, the volumetric size of the pattern is (a) bigger than, (b) same size as, or (c) smaller than the cast part?
bigger than
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?
greater than
Most widely used casting process
sand casting
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?
time between pouring and complete solidification