Cylindrical two-stage reduction gear with specification

Contents

Contents

Introduction

1. Initial data for development of course work

2. General provisions

2.1. Design and technological characteristics of the product

2.2. Volume of product production. Production type

3. Gearbox Assembly Process

3.1. Analyze or develop product specifications

3.2. Build Sequence Development

3.3. Development of routing process of assembly

4. Manufacturing process of stepped shaft

4.1. Utility and Part Specification

4.2. Selection of the workpiece and its manufacturing method

4.3. Development of routing process of part manufacturing

4.4. Calculation of tolerances and cross dimensions

4.5. Development of technological operations

4.6. Calculation of cutting modes

4.7. Technical rationing

Conclusion

List of literature

Material Inventory

Applications

Introduction

Mechanical engineering is the most important industry that determines scientific and technological progress and has a decisive influence on the creation of the material base of the new society. The level of development of mechanical engineering depends on the quality of products, labor productivity and the quality of equipment produced

The equipment used in various industries is very diverse. Along with this, in the engineering industry there are all types of production - from single to mass. These features create some difficulties in generalizing and describing the technology for manufacturing oil and gas equipment. At the same time, despite these differences, all the variety of oil and gas equipment is united by the fact that all its representatives are industrial products. In view of the fact that the development of manufacturing processes should be based on their service purpose, accuracy requirement and volume of production, it is of great interest to select from the whole variety the most characteristic objects covering a certain group of products and meeting the above three requirements.

This trend requires increased attention to the standardization and improvement of the technological process, the application of new and advanced technologies in the development of the technological process. It is the development of drawings and technological documentation related to the choice of the necessary accuracy of surfaces and roughness, the justification of landings, taking into account the technological features of processing by the selection of instrumentation, the calculation of dimensional chains, and especially with reasonable rationing of deviations in shape and location, that primarily forms the qualitative indicators of machine-building products.

In the course work, the technical requirements for the manufacture of parts and the assembly of the product are justified, the technological process of assembling the reduction gear and the manufacture of the gear wheel has been developed, measuring means for controlling the gear wheel, cutting modes have been selected, and route and operating cards have also been filled.

Initial data for development of course work

The initial data in the design of the process processes of assembly and product and process processing are:

1. Assembly drawing of gearbox article;

2. Part drawing - gear wheel;

3. Product Specification;

4. The annual production volume of the product is 5000 pcs;

5. The duration of product production is 3 years .

General provisions

2.1. Design characteristics of the product.

Before you begin to develop the assembly process, you need to familiarize yourself with the utility of the machine.

A reduction gear is a mechanism consisting of gear or worm gears, made in the form of a separate unit and serving to transfer rotation from the shaft of the engine to the shaft of the working machine .

In this course work, a reduction gear with a two-stage cylindrical gear was developed.

The service purpose of the reduction gear is to reduce the angular speed and, accordingly, increase the torque of the driven shaft compared to the driving one.

The reduction gear consists of a housing in which the transmission elements are located - gears (cylindrical), shafts (driving, intermediate and driven), bearings, etc.

Two-stage cylindrical reduction gear is considered in course work. Its maximum gear ratio according to GOST 218566 umax = 12.5.

Actuating surfaces of reduction gear are involute surfaces of teeth of cylindrical gear. When the input shaft of the reduction gear is rotated, torque is transmitted by means of a toothed involute engagement to the intermediate shaft, and then to the output shaft. Input and output shafts are installed in radial thrust bearings GOST 832875, and intermediate shaft is installed on.

Attachment of the cover to the housing is performed by bolts M14 on the flanges of the housing and cover. Bearing covers are attached to the housing by M16 screws.

2.2. Volume of product production. Type of production.

The basis for selecting the production type and organizational form of the assembly is the annual production program, which includes the item and the volume of product production for each name. There are three types of production: single, serial and mass.

Since the weight of the reduction gear is less than 200 kg and the annual output of the product is 5000 pcs, we choose the average production type. [4, 13 pages]

Serial production is characterized by a limited range of products manufactured (repaired) in periodically repeated batches. Depending on the number of products in the batch, small, medium and large-scale production is distinguished. Characteristics of repetitive manufacturing :

assigning multiple operations to each workplace; the use of universal and specialized machines for the manufacture of basic parts; Processing blanks according to a process plan divided into operations arrangement of equipment according to processing process; use of special devices and tools, etc.

Product Assembly Process (Assembly)

3.1. Analyze or develop product specifications.

This type of reduction gear has high efficiency and significant durability.

Specifications provided during gearbox assembly [4]:

1. Distance between axes of dividing circles of gears -132 mm, permissible deviations within ± 0.08 mm (GOST 164381).

2. The lateral clearance in the gear train is within 0 mm.

3. Axial clearance in shaft bearings within 0 + 0.1 mm.

4. In accordance with GOST 164381, the total contact spot must be at least 30% in height and at least 40% in length of the tooth size.

5. Clearance between sealing surface of shafts and inner surface of labyrinth seals within the limits of 0 + 0.1 mm.

6. The axis of rotation of the dividing circle of the driven shaft is parallel to the axis of rotation of the dividing circle of the intermediate shaft, permissible deviations within ± 0.085/300 mm.

7. The axis of the driven shaft is parallel to the plane of the base of the gearbox housing, permissible deviations within ± 0.435/300 mm.

8. Torque of bolts flanges is not less than 240 kgf • cm, torque of bearing covers is not less than 198.4 kgf • cm, tightening is performed in two receptacles in the following order: nuts of flange bolts, bolts of bearing covers; stop by gasket of spring washers (GOST 640275).

9. Noise level (not more than 80 dB) shall be within permissible limits.

3.2. Develop an assembly sequence.

The sequence of the general assembly of the product is determined by its structural features and the methods laid down in the design to obtain the required accuracy. The shape of the assembly process has less effect on the product assembly sequence.

The housing is the base part in the gearbox structure, which provides the necessary relative position of the remaining parts and assembly units. Therefore, the gearbox assembly should begin with the installation of the housing on the assembly bench. After the housing is installed on it, all assembly units and parts are sequentially installed.

The product assembly sequence is shown as an assembly flow chart. It shows the structure and picking order of the product and its components.

Based on the study of the purpose of the gearbox, its assembly and working drawings and the intended volume of output, we choose the organizational form of the assembly - a stationary assembly with the dissection of work, which involves dividing the process into a node assembly and a common gearbox assembly. At the same time assembly of each group and common assembly of reduction gear is performed at the same time by several assemblers. Basic part in common assembly - housing 9, in unit assembly - shafts 3, 6.

Workstations shall be equipped with assembly stands, benches, assembly and instrumentation tools, vehicles (roller table, trolleys).

3.3. Development of route process of reduction gear box assembly.

The developed process of gearbox assembly is given in the roadmap, issued in accordance with the requirements of GOST 3.1407 (Appendix 1).

Conclusion

During the course work, we developed the technological process of assembling the cylindrical reduction gear, the technological process of machining the gear wheel.

The technical specifications for the product, its service purpose, performance indicators, reliability indicators, technical requirements were analyzed. We chose a method to achieve the required accuracy of the gearbox assembly. Developed a product assembly scheme.

An analysis of the service purpose and technical conditions for the gear wheel was carried out. They chose methods for obtaining a blank - forging in backing dies, made a dimensional analysis of technological processes in mechanical engineering during the manufacture of the wheel.

Allowance and interchange dimensions, cutting mode and technical rationing were calculated.

A special machine tool was selected and calculated.