辽宁石油化工大学：《机械制造技术基础》课程教学资源（PPT课件）Chapter 06 机械加工工艺规程的制定 The Process Planning of Mechanical Manufacturing

遼字石油化工大學⊙ Chapter Sⅸ The Process Planning of Mechanical Manufacturing

Chapter Six The Process Planning of Mechanical Manufacturing

遼字石油化工大學⊙ Instructional objectives At the end of this lesson the student would be able to (1)Understand the process of product and the process of part, master the composition of the process of product (2 )Understand the content and steps of the machining process planning and focus on the main problems to be solved when formulating the machining process planning (3 )Understand machining metal removel and its influencing factors master the determination of process size and tolerance (4)Understand the definition and characteristics of dimensional chains master its composition and the basic calculation formula of it. master the analysis and calculation of dimensional chains with emphasis

Instructional objectives At the end of this lesson, the student would be able to : (1) Understand the process of product and the process of part, master the composition of the process of product. (2) Understand the content and steps of the machining process planning, and focus on the main problems to be solved when formulating the machining process planning. (3) Understand machining metal removel and its influencing factors, master the determination of process size and tolerance. (4) Understand the definition and characteristics of dimensional chains, master its composition and the basic calculation formula of it. Master the analysis and calculation of dimensional chains with emphasis

遼字石油化工大學⊙ Introduction The purpose of mechanical machining is to turn a kind of raw material into the finished parts that meet the requirement of the produce Under given manufacture conditions, how to apply both an economical and efficient method, as well as a rational process roution, to achieve the desaired parts is the concern of this chapter

Introduction The purpose of mechanical machining is to turn a kind of raw material into the finished parts that meet the requirement of the produce. Under given manufacture conditions, how to apply both an economical and efficient method, as well as a rational process roution, to achieve the desaired parts is the concern of this chapter

遼字石油化工大學⊙ 6.1 Manufacturing process AImportant concepts 1. Process of product: Manufaturing is the utilization andmanagement of materials, people, equipment, and money to produce products. For successful adn ecomomical manufacturing to be achieved, lanning must start at the design stage and continue through the selection of materials, processes, equipment, and the scheduling of production 2. Process of Part: The Process by which the shape dimensions and performance of raw material or rough casting are changed directly by mechanical manufacturing into desiged parts is called component manufactured part production, or process route

6.1 Manufacturing Process A.Important Concepts 1. Process of product: Manufaturing is the utilization andmanagement of materials,people,equipment, and money to produce products.For successful adn ecomomical manufacturing to be achieved, lanning must start at the design stage and continue through the selection of materials, processes,equipment, and the scheduling of production. 2. Process of Part: The Process by which the shape, dimensions and performance of raw material or rough casting are changed directly by mechanical manufacturing into desiged parts is called component manufactured part production,or process route

遼字石油化工大學⊙ 3. Operations: When one operator or a group of operators) works in a definite position (one machine tool or clipping table )to achieve the continous manufactruing of one or several parts simultaneously. An operation is the basic element of process procedure as well as of the production schedule and of cost estimation 200 Example1 B,s30 590 Fig. 6. 1 the engneering drawing of a shaft

3. Operations: When one operator (or a group of operators) works in a definite position (one machine tool or clipping table ) to achieve the continous manufactruing of one or several parts simultaneously. An operation is the basic element of process procedure as well as of the production schedule and of cost estimation. Example1: Fig.6.1 the engneering drawing of a shaft

遼字石油化工大學⊙ Analysis: If the number of the parts in a batch is small, the manufacturing process can be completed through 5 operations, which are shown in table 6-1 For the manufacturing of the same part, if the number of part is large, the operation 1 in table 6-1 can be divided into 2 operations a)facing and centering one end in an engine lathe by one operator b)transferring to another engine lathe for facing and centering the another end by another operator. table 6-1 the process of shaft manufacturing Operation No peration name Work place facing end. center drilling ends Engine lathe 2 Cylindrical Turning Engine lathe Key way milling Upright milling machine Cylindrical grinding Grinding machine 6 deburring Clipping table

Analysis: If the number of the parts in a batch is small, the manufacturing process can be completed through 5 operations, which are shown in table 6-1. For the manufacturing of the same part, if the number of part is large, the operation 1 in table 6-1 can be divided into 2 operations: a) facing and centering one end in an engine lathe by one operator. b) transferring to another engine lathe for facing and centering the another end by another operator. table 6-1 the process of shaft manufacturing

遼字石油化工大學⊙ 4. Operation Step: An operation step is the basic element of an operation. One operation step is defined as an operation that is completed under the condition when the surface to be manufactured the cutting parameters and cutting tool remain the same. When any of the cutting parameters is changed, it will become another operation 5. Cutting pass: When the amount of metal to be removed is large, several cutting passes may need to be carried out a cutting pass is a kind of operation step that is completed by a single type of tool to cut the same surface under the same cutting parameters

4. Operation Step: An operation step is the basic element of an operation. One operation step is defined as an operation that is completed under the condition when the surface to be manufactured, the cutting parameters and cutting tool remain the same. When any of the cutting parameters is changed, it will become another operation step. 5. Cutting pass: When the amount of metal to be removed is large, several cutting passes may need to be carried out. A cutting pass is a kind of operation step that is completed by a single type of tool to cut the same surface under the same cutting parameters

遼字石油化工大學⊙ 6. Operation position: In order to reduce the number of setups, a rotational worktable or fixture is usually used to make sequential machining in different positions possible from a single setup. The job performend in one position is called one operation position Demontration of operation, operation step, position and cutting pass

6. Operation position: In order to reduce the number of setups, a rotational worktable or fixture is usually used to make sequential machining in different positions possible from a single setup. The job performend in one position is called one operation position. Demontration of operation, operation step, position and cutting pass

遼字石油化工大學⊙ B Production Type and its impact on process planning 1. Production type: refers to the specialized classification of an enterprise in respect of a workshop, manufacturingline or group, work place, and so on. Generally, it can be classified into 3 types, which are, a)single Production The number of workpieces with different structure or different dimensions is only one at a time, or only in small quantity For example: heavy-duty machines, specialized machines and new products o)Batchs The number of the same products in one batch. Including small batch large batch and medium batch

B.Production Type and its impact on process planning 1. Production type: refers to the specialized classification of an enterprise in respect of a workshop, manufacturingline or group, work place, and so on. Generally, it can be classified into 3 types, which are, a) Single Production: The number of workpieces with different structure or different dimensions is only one at a time, or only in small quantity. For example: heavy-duty machines, specialized machines and new products. b) Batchs: The number of the same products in one batch. Including: small batch, large batch and medium batch

遼字石油化工大學⊙ c)Large quantity production: The quantity of each part being produced is large, and many work places often manufacture the same product, carrying out the same operations on each example of the product repeatedl For eXample: the manufacturing of vehicles, trucks and bearings 2. Impact on process planning Process planning are highly affected by the produciton type When the produciton type changes, the production organization and management, the layout of workshop and machine tools, the process method of the raw material, the manufactruing equipment, such as kinds of cutting tool, fixture and inspeciton tools and the technical level of the operators will also varied addordingly

c) Large quantity production:The quantity of each part being produced is large, and many work places often manufacture the same product, carrying out the same operations on each example of the product repeatedly. For example: the manufacturing of vehicles, trucks and bearings. 2. Impact on process planning Process planning are highly affected by the produciton type. When the produciton type changes, the production organization and management, the layout of workshop and machine tools, the process method of the raw material, the manufactruing equipment,such as kinds of cutting tool, fixture and inspeciton tools and the technical level of the operators will also varied addordingly