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1、2021/6/13,SCUT,1,3.8 The function and design method of process planning file,The term process route(工藝規(guī)程) refers to the process planning file in which the process and operation method are specified. In another word, the sequence of each operation, the part dimensions, tolerance and technical require

2、ment, technical equipment and measures, cutting parameters, standard production time, and levels of operators skill are all included in the process planning file.,2021/6/13,SCUT,2,3.8.1 The format of a process sheet工藝過(guò)程卡,The format of a part process sheet made by different companies is quite differe

3、nt. In 1982, the pre-mechanical industry ministry(原機(jī)械工業(yè)部） issued the ministry standard to regulate the format of a part process sheet (referred to JB/Z1 187.3-82). Nevertheless, operation sheets are largely identical but with minor differences. Usually the following items should be included in a pro

4、cess sheet. Name of part and type ； Name and No. of part ； Raw material ； Name of operation ； Name of plant .,2021/6/13,SCUT,3,In single or small batch type production, only a general and simple process planning sheet is prepared, shown as the following sample, where the product name and type, part

5、name and drawing No., the kinds and material of the roughcast, operation No. name and content, the workshop for each operation, equipments and time scheduling are all included.,3.8.1 The format of a process sheet工藝過(guò)程卡,2021/6/13,SCUT,4,process planning sheet,3.8.1 The format of a process sheet工藝過(guò)程卡,2

6、021/6/13,SCUT,5,In Batch type production, usually a detailed operational sheet is planned, show as the sample given below, in which not only the content of a process sheet must be included ,but also the detailed description of the operational step and position, the operational dimensions and specifi

7、cations are included. An operational draft should be given for some main operations, in which the desired dimensions achieved in that operation, the tolerance, the roughness and the setup must be marked. In single or small batch type production, some important parts also ask for an operational sheet

8、.,3.8.1 The format of a process sheet工藝過(guò)程卡,2021/6/13,SCUT,6,operational sheet,3.8.1 The format of a process sheet工藝過(guò)程卡,2021/6/13,SCUT,7,Part operational draft,3.8.1 The format of a process sheet工藝過(guò)程卡,2021/6/13,SCUT,8,Before products are manufactured, technical and production preparation can be made

9、according to the demands of process planning sheet.,According to the process planning sheet, the kinds, type and number of machine tools, the production area needed , the plan arrangement of equipment, the number, type and class of operators required can all be decided. Then, the planning of factory

10、 preparation, enlarging or rebuilding will be decided accordingly.,3.8.1 The format of a process sheet工藝過(guò)程卡,2021/6/13,SCUT,9,The functions of process planning sheet,The functions of the process planning sheet are as follows ： (1)The main technique for giving regulations to guide the production. (2)

11、The basis of organization and management. (3) The main information to guide the building, enlarging or rebuilding of a mechanical factory.,3.8.1 The format of a process sheet工藝過(guò)程卡,How to design the machining process of a workpiece?,2021/6/13,SCUT,10,2021/6/13,SCUT,11,3.8.2 The analysis of the proces

12、sing performance (加工性分析）,1 . Inspect the design drawing：check if the dimensions are complete and structural expression is clear. 2. Analyze if the specifications are reasonable, including: （1）The dimensional accuracy；（2）The geometrical shape accuracy；（3）The positional accuracy between the main machi

13、ned surfaces （4） Requirement of the surface quality；（5） Requirement of the heat treatment .,Step 1,3、Check if the material is properly chosen Use the usually used material as far as possible if it meets the requirement, such as 45 steel,3.8.2 The analysis of the processing performance (加工性分析）,The de

14、termination of raw material is related with the part geometrical shape, dimensions, mechanical performance of material and production type, current production conditions of the workshop.,Casting,includes cast steel, cast iron, cast alloy etc. The shape of the casts can vary from complication to simp

15、licity, and dimensions can be very large.,Forging,has better mechanical performance than castings, however. many intricate and cored shapes possible in casting cannot be forged.,Profiled bar,The shape of cross section can be round, rectangular or other different shapes. Bars are often machined into

16、shafts, dishes or round shells with engine lathe, turret lathe, or automatic or semi automatic lathe, and the dimensions can vary from small to medium size. but its thickness is limited within a range.,Welding,for complicated and large parts can be welded from profiled bar or forged parts，but the welded part performs badly in some respects.,Engineering plastic,used widely in mechanical manufacturing in recent years. Its shape can vary from simple to complicated, and the dimension accuracy is hig