Processing process of rear roller part

Contents

INTRODUCTION

1TECHNOLOGICAL SECTION

1.1The purpose and design of the machined part

1.2 Determination of workability of part design

1.2.1 Qualitative analysis

1.2.2 Quantitative Analysis

1.3Specification of production type

1.4 Selection and justification of procurement method

1.5 Calculation of machining allowances

1.6 Calculation of cutting modes

1.7 Calculation of technical time norm

1.8 Selection of equipment and calculation of its quantity

1.9 Feasibility Study of Process Option

CONCLUSION

LIST OF LITERATURE

APPLICATION

Introduction

As the development of industrial production of recent years shows, in the field of mechanical engineering technology, one of the main areas is the development of methods for optimizing technological processes in terms of accuracy, productivity, provided that high operational qualities and reliability of the machine are ensured. This direction is considered in this course project.

The purpose of this course project is to develop a processing process based on the base part "Rear Roller."

The drawing of the manufactured part "Rear Roller," the basic manufacturing process of the part, is used as the initial data for the upcoming design. The mode of operation in the manufacture of the part is taken as two-shift, in accordance with the task for the course design. The volume of production is 9,500 pieces per year. The following tasks were solved in the course project:

1. The workability of the part has been determined.

2. Production type is defined.

3. Basic technological process is analyzed and process is developed on the basis of it.

4. The procurement method is selected and justified.

5. Calculation of machining allowances and calculation of cutting modes were performed.

6. The technical time limit has been calculated.

7. Feasibility study presented

1.2 Determination of workability of part design

Each part must be manufactured with minimum labor and material costs. These costs can be reduced to a large extent by the correct choice of the process variant, its equipment, mechanization and automation, the application of optimal processing modes and proper preparation of production. The construction and manufacturing requirements of the part have a particular impact on the labour input of the part. Processability is the most important technical basis that ensures the use of design technological reserves. Rules of part design development for processability are given in GOST 14.20383.

Evaluation of workability of the part design is carried out according to two indicators: qualitative and quantitative.

1.2.1 Qualitative analysis

The "Rear Roll" part is made of 40XGNM steel, so the configuration of the loaded loop does not cause significant difficulties in obtaining the part. Since the part is a body of revolution, most chipbreaking operations can be performed on lathes.

From the point of view of machining, the chamfers are non-technological in 30˚, they are determined by structural considerations and it seems difficult to change them.

The surfaces Ø16k6 are required as they are the bearing support elements. These surfaces shall be made within the specified deviations and with roughness Ra 0.8. The only way to achieve this accuracy is

final grinding on circular grinding machines.

Also non-technological elements are two slot holes 6x4.5x12 on the surface Ø25 since its manufacture requires the use of a key cutter on a vertical milling machine.

Otherwise, the part is technological. The part allows the use of high-performance processing modes, has good base surfaces for initial operations. This part can be manufactured on universal and specialized equipment with a standard cutting tool, and depending on the volume of production, CNC equipment and machining centers can be used. Therefore, this part is technological.

Conclusion

The "Rear Roller" part is technological in terms of processing accuracy and roughness factors. As a method of obtaining a workpiece, MCC stamping is used.

For "Rear roller" part with annual volume of production

N = 9,500 pieces/year according to the obtained values, the production type is large-scale. The allowances for processing the most accurate surface are calculated - the outer surface of the roller ∅16k6. The cutting modes for operation "015 Milling with NC" and the technical normalization for operation "025 Drilling with NC" were calculated.

The annual economic effect of the use of stamping on GKM amounted to 6,279,500 rubles compared to the production of this stock.

In the process of developing a technological project, the task set for us was solved. The following changes have occurred in the developed process plan compared to the basic one:

reduced processing time for the part;

the labor intensity of manufacturing a unit of production decreased, since optimal cutting modes were adopted, the share of auxiliary time mainly decreased.