Electronic technology 20th autumn "Introduction to machine manufacturing" online assignment 3 [standard answer]

20 autumn 《 Introduction to mechanical manufacturing 》 Online homework 3
1.[ Single topic selection ] Economic machining accuracy refers to the use of a certain machining method （）.
A. The highest accuracy that can be achieved
B. The average accuracy that can be achieved
C. Accuracy guaranteed under normal conditions
D. Accuracy guaranteed under the most unfavorable conditions
answer :——C——
2.[ Single topic selection ] The material suitable for manufacturing gear cutters is （）
A. Carbon tool steel
B. High speed steel
C. Carbide
D. Ceramic materials
answer :——B——
3.[ Single topic selection ] drill 、 expand 、 Among the three machining methods , The highest machining accuracy is （）
A. drill
B. expand
C. hinge
D. Cannot compare directly
answer :——C——
4.[ Single topic selection ] One of the main reasons for the heavy energy of forgings is （）
A. Overheated
B. Overburning
C. Large deformation resistance
D. Poor plasticity
answer :————
5.[ Single topic selection ] When turning the screw rod , Causes of pitch cumulative error （）
A. Radial displacement of machine tool spindle
B. The lathe spindle moves axially
C. Machine tool transmission chain error
D. Tool wear
answer :————
6.[ Single topic selection ] The composition of the machining process system is （）
A. The cutting tool 、 Measuring tool 、 Fixtures and accessories
B. Machine tool 、 fixture 、 Knives and accessories
C. Machine tool 、 fixture 、 Tools and measuring tools
D. Machine tool 、 fixture 、 Tools and workpieces
answer :————
7.[ Single topic selection ] The included angle between the rake surface and the base surface measured in the orthogonal plane is ()
A. Front corner
B. Back corner
C. Principal deflection angle
D. Blade inclination angle
answer :————
8.[ Single topic selection ] Machining an outer circle of quenched steel , The processing sequence is （　　）.
A. turning － quench － Grinding
B. turning － Grinding － quench
C. quench － turning － Grinding
D. turning － quench － turning
answer :————
9.[ Single topic selection ] The sensitive direction of error is （）
A. Main motion direction
B. Feed movement direction
C. The normal direction of the machined surface passing through the tip
D. The tangential direction of the machined surface passing the tip
answer :————
10.[ Single topic selection ] When organizing the process according to the principle of process concentration , The following statement is wrong （）
A. Fewer processes , Less equipment , The number of operators and production area can be reduced accordingly
B. It is conducive to the adoption of efficient machine tools and process equipment with a higher degree of Automation , High productivity
C. The technical level of machine tool operators is not high
D. numerical control machine 、 Most machining centers use the principle of process concentration to organize the process
answer :————
11.[ Single topic selection ] The frequency of forced vibration is equal to （). University of Electronic Science and technology answer q Or come in
A. The frequency of the disturbing force
B. Frequency of process system
C. The frequency of the disturbing force or its integral multiple
D. Frequency of weak links in the rigidity of the process system
answer :————
12.[ Single topic selection ] Which of the following methods can be used to improve machining productivity ？（）
A. Adopt advanced and efficient production equipment
B. Improve the operation level of workers
C. Modify the product design
D. Increase operators
answer :————
13.[ Single topic selection ] When finishing , Should be selected （　） Cooling .
A. Aqueous solution
B. Emulsions
C. Cutting oil
D. Higher temperature aqueous solution
answer :————
14.[ Single topic selection ] In machining , Linear wear of tools belongs to （）
A. Constant systematic error
B. Variable systematic error
C. Random error
D. Gross error
answer :————
15.[ Single topic selection ] The Eutectic Transformation of metal materials in the crystallization process refers to ()
A. Crystallize a solid phase from a liquid phase
B. Two different solid phases crystallize from a liquid phase
C. From one solid phase to another
D. From one solid phase to two different solid phases
answer :————
16.[ Single topic selection ] When cutting , Which of the following factors has no effect on surface roughness ？（）
A. Tool geometry
B. Cutting parameters
C. Workpiece material
D. test method
answer :————
17.[ Single topic selection ]． The structural manufacturability of parts refers to （）.
A. The influence of part structure on strength
B. The influence of part structure on machining feasibility
C. The influence of part structure on service performance
D. Influence of part structure on stiffness
answer :————
18.[ Single topic selection ] The rigidity of the process system is equal to that of the machine tool 、 fixture 、 Tool and workpiece stiffness （）.
A. The sum of the
B. Product of
C. Reciprocal of the sum of the reciprocal
D. The reciprocal of the reciprocal product
answer :————
19.[ Single topic selection ]“16Mn” Refer to （）
A. Carburized steel
B. Quenched and tempered steel
C. chisel tool steel
D. Structural steel
answer :————
20.[ Single topic selection ]（） Is a constant systematic error
A. Machine tool 、 Manufacturing error of fixture
B. Tool thermal elongation
C. Internal stress redistribution
D. Linear tool wear
answer :————