In an expansion molding operation, why does fusion occur in the mold and not in the pre-expansion step?
What will be an ideal response?
The beads are confined in the molding step and therefore expand against each other. This close contact forces the walls of neighboring beads to meet and, if the temperature is high enough, fusion occurs. During pre-expansion, the beads are in an air flow and therefore do not have intimate contact with each other. To further prevent beads from fusing during pre-expansion, the temperature is often a few degrees lower than during molding. Also, liquids can be added during pre-expansion that tend to keep the beads separated.
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cholesterol level in eggs.
Indicate whether the statement is true or false.Using Ohm?s law, find V when the current I = 4.2 mA and R = 1.5 k?
What will be an ideal response?
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Fill in the blank(s) with the appropriate word(s).
Direct expansion evaporators have ____.
A. expansion joints between sections of the evaporator B. an established superheat at the outlet of the evaporator C. subcooling at the outlet of the evaporator D. an established superheat at the inlet of the evaporator