Refrigeration and Air Conditioning Technology (MindTap Course List)
8th Edition
ISBN: 9781305578296
Author: John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher: Cengage Learning
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Chapter 8, Problem 18RQ
Why is it important to change the oil on a vacuum pump after each evacuation?
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Ex. Determine the safety factors for the bracket rod based on
the distortion "energy theory and max. shear theory
both
Given:
L= 6 in
held 47000 Psi
and material is ductile.
a = 8 in
d = 1.5 in
F = 7000-16
arm
し
Tod
F
a
d
Ex. For a plate that made from a brittle material alloy shown below,
Find the max. stress that occur.
P=5KN
d=2cm
w= 10 cm
t=0.2 cm
Ex. A circular cantilever rod, shown in the Fig. below, is to be made
* from al ductile material with field strength of 276 MPa Using
design factor N = 2
factor N = 2, Find the appropriate diameter(d).
d
F= 1.75 KN
P=9KN
120mm
Chapter 8 Solutions
Refrigeration and Air Conditioning Technology (MindTap Course List)
Ch. 8 - The low-pressure side of the system must not be...Ch. 8 - Name and briefly describe the six classes of...Ch. 8 - The ________is both the greatest asset and the...Ch. 8 - Why should oxygen or compressed air never be used...Ch. 8 - List some of the foreign matter that may enter a...Ch. 8 - True or False: A vacuum pump can remove any type...Ch. 8 - Air in a refrigeration system causes which of the...Ch. 8 - The only two products that should be circulating...Ch. 8 - In order to remove moisture from a refrigeration...Ch. 8 - Are the best vacuum pumps one-stage or two-stage?
Ch. 8 - Name the two types of vacuum procedures used by...Ch. 8 - What can be done to get water out from under the...Ch. 8 - When evacuating a refrigeration system that has...Ch. 8 - What is today's most accurate type of deep vacuum...Ch. 8 - _________microns are in 1 inch.Ch. 8 - Briefly describe the method for cleaning up a...Ch. 8 - What is the advantage of using large gauge lines...Ch. 8 - Why is it important to change the oil on a vacuum...Ch. 8 - Describe the meaning of a deep vacuum, and explain...Ch. 8 - List the main advantages of a microfoam leak...Ch. 8 - What could an oily dust spot on a condenser or...Ch. 8 - Why should a condenser be covered with a sheet...Ch. 8 - Leaks that occur only when the unit is in...Ch. 8 - Briefly describe a combination-dependent leak.
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