Machining of shaft-gear type part

Contents

Entry

1. Calculation of output volume and determination of production type

2. General characteristic of the child

2.1. Service assignment of a child

2.2. Child-lee type

2.3. Analysis of workability of a child

2.4. Standard control and metrological examination of part drawing

2.4.1. Selection of rational nomenclature of controlled parameters

2.4.2. Analysis of correctness of standard setting

2.4.3. Shape and Roughness Compliance Analysis

permissible time-measure

2.4.4 Analysis of correct selection of bases and location tolerances

3. Procurement type selection and justification

4. Development of a routing process for the manufacture of parts

5. Operational Process Development

5.1 Equipment refinement

5.2 Calculation of Operating Sizes and Sizes of Corners

5.3 Selection of working devices

5.4 Purpose of cutting tools

5.5 Calculation of cutting modes

5.6 Technical Standards

6. Metrological support of the process

7. Process System Safety

Lead-outs

Literature

Introduction

The current pace of scientific and technological progress causes significant changes in the field of production of all industries, where samples of products are constantly being improved and updated. In this regard, the need for systematic restructuring of production to significantly increase the volume of products produced in single, small-scale and serial production is increasing. In addition to solving automation problems, the tasks of ensuring the flexibility of production systems capable of quickly adjusting to the production of new products are of great importance.

During development of process processes of parts processing in automated areas it is necessary to solve the following tasks:

- increase of workability of parts;

- improving accuracy and quality of blanks; ensuring stability of the allowance; improvement of existing and creation of new methods of production of billets, which reduce their cost and metal consumption;

- increasing the degree of concentration of operations and the related complexity of structures of machine process systems;

- development of advanced technological processes and structure-and-layout diagrams of equipment, development of new types and structures of cutting tool and devices providing high productivity and quality of processing;

- development of aggregate and modular principle of creation of machine systems, loading and transportation devices, industrial robots, control systems.

In basic production (PKB OJSC), universal machines with elementary settings are used for the manufacture of parts as main equipment. The equipment is located in groups, with the formation of sections. Technological processes are built on the principle of differentiation of operations.

Mechanization and automation of machining processes provides for maximum reduction of manual labor associated with transportation, loading, unloading and processing of parts, change and adjustment of tools, as well as work on collection and processing of chips.

In such production, a person is partially exempt from direct participation in the manufacture of the product. Behind it are the functions of tooling preparation, adjustment, programming, computer maintenance. The proportion of mental labour is increasing and the proportion of physical labour is minimized. The number of workers is declining. The requirements for the qualification of workers serving automated production are increasing.

3. Procurement type selection and justification

The main thing when selecting a workpiece is to ensure the specified quality of the finished part at its minimum cost. The method of obtaining the workpiece is determined by its design, purpose, material, technical requirements for manufacturing and its cost effectiveness, as well as the volume of production. The method of obtaining the workpiece, its type and accuracy directly determine the accuracy of machining.

The choice of the method of obtaining the workpiece was based on the analysis of possible production methods, the implementation of which can contribute to the improvement of technical and economic indicators, that is, to achieve maximum efficiency while ensuring the required quality of the product.

Rolled stock is used for a certain class of simple parts, such as small rollers, fasteners, rollers. Characteristic of mass and large-scale production.

For parts working on bending, stretching, torsion, blanks of forging and stamping type are used.

Forgings can be obtained by free forging, which is used for large parts, allowances range from 12 to 70 mm. Decay is required during processing. Equipment: steam-air hammers, hydraulic presses. Characteristic of single production.

Among the technological processes of low-waste production of blanks are: obtaining accurate hot-stamped blanks with minimal waste in the cloud, manufacturing blanks by cold stamping or heating.

Stamping is a more productive process. The workpiece applies a shape closer to the part shape. It is carried out in a stamp. Equipment crank presses, horizontal forging machines. Accuracy 15 qualities and rougher. Characteristic of mass production and mass production.

A progressive method of stamping is cold extrusion. For cold extrusion of blanks, hydraulic presses are used, which allow to automate the process. Setting the maximum force at any point in the stroke of the slider on hydraulic presses allows you to press long parts.

It is preferable to obtain stamping on GSM, where it is possible to form blanks weighing up to 100 kg (stepped shafts, gear shafts, flanges). The dimensional accuracy of steel forgings can reach 1214 square meters, a para-meter of surface roughness Ra12.5Ra25.

The shaft blank can be obtained by means of a process of transverse wedge rolling, which provides a sharp reduction in metal consumption and an increase in productivity. This method gives the workpiece configuration closest to the part configuration, the highest accuracy and the best surface quality. The dimensional accuracy of steel forgings can reach 1112 square meters, roughness parameter Ra3.2Ra1.6.

Obtained forgings are subjected to preliminary heat treatment.

The purpose of the heat treatment is:

- elimination of negative consequences of heating and pressure treatment (removal of residual stresses, evaporation of overheating);

improvement of workability of workpiece material by cutting;

- preparation of metal structure for final maintenance.

After maintenance, forgings come to surface cleaning. The workpiece sketch is presented in the graphic part of the diploma project.

The blank can be obtained by stamping in closed dies. It is used for parts of a simple shape, mainly bodies of revolution with reduced ductility.

As one of the versions of the billet production we will accept production of forging by cross-wedge rolling. This method makes it possible to obtain stampings closer to the finished part in shape and dimensional accuracy than stampings obtained by other methods. In our case, if it is necessary to manufacture a high-precision part, the minimum surface roughness of which is Ra3.2, obtaining a blank by transverse wedge rolling will significantly reduce blade processing, reduce metal consumption and machine-tool capacity.

5.1. Equipment refinement

The main type of equipment for processing parts of the type of bodies of revolution, in particular shafts, in medium-term production conditions are turning and round grinding machines with numerical program control (NC). For toothed surfaces - tooth-cutting and tooth-grinding, for milling slots - milling machines.

To process cylindrical and end surfaces, select the Mazatrol PC Fusion 640 M Pro CNC Lathe (XYZ760 * 660 * 660; table edges 500 * 500, spindle speed 15000). For finish turning and keyway milling, select the FREZER DMC1000 machine (Axial movement XYZ1000 * 1500 * 1200, max machined length 1500, spindle speed 1500)

For finishing grinding and milling we adopt the grinding machine machine 2206VMF4. (Working surface pore 630 * 800; spindle speed 3500).

For the advanced and high precision stages, the Pico Tern CNC CNC NC grinder, for the particularly high precision stage, is the MS5B. For tooth milling, a 5K328A tooth cutting machine.

For grinding of teeth of increased and high accuracy, we select the tooth grinding machine 5D833.Bases for each installation are assigned in accordance with the principle of constancy of bases and their successive alternation from stage to stage and taking into account ensuring accuracy of arrangement of machined surfaces .

5.3 Selection of working devices

Considering the adopted type and form of organization of production on the basis of a group method of processing, it can be stated that it is advisable to use specialized, fast-acting, automated readjustable devices. At turning operations, self-centering cartridges and centers are used, at grinding operations - centers. All fixtures shall contain in their design the basic part (common to the basing scheme for all parts of the group) and replaceable adjustment or adjustable elements for quick changeover when switching to processing of any of the parts of the group.

Conclusions

In this exchange rate project, the production volume was calculated and the production type was determined. The correctness of drawing execution is analyzed from the point of view of compliance with the current standards. Part processing route is designed, equipment, cutting tool and accessories are selected. The operational dimensions and dimensions of the workpiece are calculated. Cutting modes and time norm for turning operation are defined. The issues of metrological support and safety are considered.