Manufacturing Engineering & Technology
7th Edition
ISBN: 9780133128741
Author: Serope Kalpakjian, Steven Schmid
Publisher: Prentice Hall
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Chapter 14, Problem 40QTP
A solid cylindrical specimen, made of a perfectly plastic material, is being upset between flat dies with no friction. The process is being carried out by a falling weight, as in a drop hammer. The downward velocity of the hammer is at a maximum when it first contacts the workpiece, and becomes zero when the hammer stops at a certain height of the specimen. Establish quantitative relationships between workpiece height and velocity, and make a qualitative sketch of the velocity profile of the hammer. (Hint: The loss in the kinetic energy of the hammer is the plastic work of deformation; thus, there is a direct relationship between workpiece height and velocity.)
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The figure below shows a symmetric plane-strain upsetting process. The process may also be thought of as a form of side extrusion. Observations show that the deformation is confined to two shear planes, each one being analogous to that seen in plane-strain cutting. You may assume that there is no friction between the work material and the tool/die walls; the uniaxial yield strength of the material is σy and is independent of strain rate and temperature, and the material behaves as a rigid plastic solid.
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Chapter 14 Solutions
Manufacturing Engineering & Technology
Ch. 14 - What is the difference between cold, warm, and hot...Ch. 14 - Explain the difference between open-die and...Ch. 14 - Explain the difference between fullering, edging,...Ch. 14 - What is flash? What is its function?Ch. 14 - Why is the intermediate shape of a part important...Ch. 14 - Describe the features of a typical forging die.Ch. 14 - Explain what is meant by load limited, energy...Ch. 14 - What type of parts can be produced by rotary...Ch. 14 - Why is hubbing an attractive alternative to...Ch. 14 - What is the difference between piercing and...
Ch. 14 - What is a hammer? What are the different kinds of...Ch. 14 - Why is there barreling in upsetting?Ch. 14 - What are the advantages and disadvantages of...Ch. 14 - Why are draft angles required in forging dies?Ch. 14 - Is a mandrel needed in swaging?Ch. 14 - Describe and explain the factors that influence...Ch. 14 - How can you tell whether a certain part is forged...Ch. 14 - Identify casting design rules, described in...Ch. 14 - Describe the factors involved in precision...Ch. 14 - Why is control of the volume of the blank...Ch. 14 - Why are there so many types of forging machines...Ch. 14 - What are the advantages and limitations of cogging...Ch. 14 - What are the advantages and limitations of using...Ch. 14 - Review Fig. 14.6e and explain why internal draft...Ch. 14 - Comment on your observations regarding the...Ch. 14 - Describe your observations concerning the control...Ch. 14 - Prob. 27QLPCh. 14 - Describe the difficulties involved in defining the...Ch. 14 - Describe the advantages of servo presses for...Ch. 14 - List the general recommendations you would make...Ch. 14 - Which would you recommend, (a) hot forging and...Ch. 14 - Take two solid, cylindrical specimens of equal...Ch. 14 - Calculate the room-temperature forging force for a...Ch. 14 - Using Eq. (14.2), estimate the forging force for...Ch. 14 - To what thickness can a solid cylinder of 1020...Ch. 14 - In Example 14.1, calculate the forging force,...Ch. 14 - Using Eq. (14.1), make a plot of the forging...Ch. 14 - How would you go about estimating the punch force...Ch. 14 - A mechanical press is powered by a 30-hp motor and...Ch. 14 - A solid cylindrical specimen, made of a perfectly...Ch. 14 - Devise an experimental method whereby you can...Ch. 14 - Assume that you represent the forging industry and...Ch. 14 - Figure P14.44 shows a round impression-die forging...Ch. 14 - Prob. 45SDPCh. 14 - Prob. 46SDPCh. 14 - Review the sequence of operations in the...Ch. 14 - Prob. 48SDPCh. 14 - Discuss the possible environmental concerns...Ch. 14 - List the advantages and disadvantages in using a...
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