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Contents

Introduction

Define Production Type

1. General part

1.1. Service purpose and general characteristics of production facilities

1.2. Define Shop Floor Mode and Production Type

2. Process Part

2.1. Analysis of source data

2.1.1. Service purpose of the product

2.1.2. Drawing Design Control

2.1.3. Technical Specifications Analysis

2.1.4. Product Design Processability Analysis

2.2. Process Analog Selection

2.3. Select Source Procurement

2.4. Selection of process bases

2.5. Substantiation of the form of organization of production and technological route of part manufacturing

2.5.1. Workflow Justification

2.5.2.Basking of used equipment

2.6. Development of technological operations

2.7. Calculation of machining allowances and operating dimensions

2.8. Calculation of cutting modes and normalization of operations

2.9. Calculation of cost-effectiveness of process variants

List of sources used

Introduction

The current state of machine-building production is characterized by an increase in the frequency of turnover of products, an increase in the breadth of the range of products, requirements for reducing the length of the production cycle and ensuring the quality of products.

These tasks in the field of technological preparation of production systems can be solved only if the technological design is preceded by deep technological developments.

Engineering occupies an important place in the development of the national economy, it implements scientific and technical discoveries and creates the material base of all industries.

The modern level of mechanical engineering around the world requires a fundamentally new approach to the design and manufacture of new machines. This approach is based on the increasing use of modern computer technology and software complexes at almost all stages of design and manufacture. The use of computer technology in mechanical engineering processes makes it possible to dramatically reduce the time taken to create new products, especially when using databases in various industries. Computer modeling of parts and products makes it possible to evaluate some characteristics of the designed product without producing prototypes. The use of modern systems in the preparation of control programs for CNC machines and machining center machines makes it possible to process parts of high complexity with the highest accuracy. Until recently, such opportunities were practically not available. Computer-aided modeling of part processing eliminates gross errors when programming CNC machines. Using direct control of CNC machines reduces the time it takes to prepare programs for implementation on the machine.

The purpose of this course project is to consolidate knowledge in the field of theoretical foundations of mechanical engineering technology, acquire practical knowledge and skills in the development of technological processes of mechanical processing, solve specific problems in the development of new technological processes. Familiarization with technological equipment used in technological processes. Conversion of the technological process to more modern equipment to increase the productivity and quality of the product, and reduce the labor intensity of production and the cost of production of the product .

CNC equipment allows the part to be machined with high precision and with minimal reinstallation. Such machines are very easy to transfer to the production of another product. The reassignment is limited to replacing the control programs and accessories for basing and fixing the part on the machine table.

Recently, CNC equipment has become increasingly widespread not only abroad, but also in our country. This is due to the extensive capabilities of this type of equipment, simple re-adjustment, processing accuracy, and built-in capabilities. Therefore, the theme of the course project corresponds to modern trends in the development of world engineering.

At the base enterprise, the Saratov Aviation Plant, in recent years, work has been carried out on the increasing use of a fleet of CNC machines.

In practice, the use of CNC machines allows you to observe such principles as unity and consistency of bases, allows you to reduce processing time due to the maximum concentration of process operations. The introduction of CNC equipment is particularly effective in single and mass production.

Service purpose and general characteristics of production facilities

The housing part is included in the design of the grinding head. The head is designed for installation on a vertical drilling machine and serves to sharpen the cutting tool in small-scale production conditions. From the spindle of the machine through the intermediate shaft (not shown), rotation is transmitted to the hollow spline shaft 1 installed in the housing 2. Gear 3 is pressed onto shaft 1 to transmit torque to shaft-gear 4. Shaft-gear 4 rotates in rolling bearings installed in housing 5. Mandrel 6 with abrasive wheel 7 is fixed on splined end of shaft-gear 4.

Technical Specifications Analysis

The analysis and assignment of the specification is based on the service assignment of the part and is intended to verify their correct assignment.

We will analyze the main points of technical specifications:

1. Casting in sandy forms. Casting specification as per OST 190021 - 92. Monitoring Group 3.

To develop the project, the part "Housing" was proposed, which is part of the grinding head mechanism. Based on the service purpose of the part and the product in which it is included, it can be concluded that the design being developed should have the lowest mass with sufficient strength and hardness, ensuring the reliability of the product. The method of obtaining the workpiece is casting, 40X steel used to manufacture this part.

The part workpiece belongs to the 3rd inspection group. This means that castings belonging to this group are subject to a selective strength test.

2. Casting accuracy 3-0-0-7 GOST 26645-85

This specification means that the casting belongs to class 3 dimensional accuracy and class 7 mass accuracy. The degree of warping and the displacement tolerance of the casting may not be specified.

3. Unspecified limit deviations as per OST 100022 - 80.

This standard establishes limit deviations of linear and angular dimensions, fillet radii, as well as tolerances of deviation of the form and arrangement of smooth surfaces of parts elements obtained by various methods of processing from any materials, limit deviations and tolerances, which are not marked on the drawings for dimensions or technical requirements directly with numerical values or established symbols of tolerance fields. All enclosing elements are performed according to H14, covered by h14, other elements ± t2/2.

4. Misalignment tolerance of surfaces B, C and D is not more than 0.05 mm.

Tolerance of deviation from coaxiality relative to common axis is the largest distance Δ between the axis of the considered rotation surface and the common axis of two or several rotation surfaces on the length of the normalized section.

5. The run-out tolerance of surfaces B and C relative to surface D is not more than 0.05 mm.

The surface run-out tolerance relative to the axis is the deviation of the angle between the plane and the base axis from the right angle, expressed in linear units on the length of the normalized section.

6. Tolerance of non-perpendicular surface E relative to surfaces B and B is not more than 0.05 mm.

Deviation from perpendicular of planes - deviation of angle between planes from right angle, expressed in linear units Δ on length of normalized section.

7. Deviation of mounting surfaces B, C, E for bearings as per GOST 332585, for 6 accuracy class.

Deviations from the correct geometric shape of the landing surfaces are assigned in accordance with GOST 3325-85. This standard applies to shafts (axes) and holes of the bodies of machines and mechanisms, the seats of which are intended for rolling bearings manufactured according to current standards. In accordance with this GOST, the permissible deviation from the correct geometric shape of the landing surfaces should take the following values: by ovality - no more than ¼ tolerance for diameter in any section of the landing surface; by taper (difference of diameters in extreme sections of the landing surface) - not more than ¼ tolerance for diameter of the landing surface.

Roughness parameter of mounting holes of housings with nominal diameter up to 80mm shall not exceed 0.8mkm; more than 80 up to 500 mm - 0.8 ÷ 1.6 microns.

When analyzing the values of the permissible limit deviations of the shape and mutual position specified in the technical requirements, it can be concluded that these values ​ ​ meet current standards and ensure the required accuracy of the regulated surfaces to fulfill their service purpose.

8. Mark and mark with PO-5 font, GOST 293062.

Software - capital font, main (Russian, Latin, Greek, Arabic numbers); 5 is the height of the font in mm. The quality of the products manufactured by the manufacturer for the correctness of individual operations of its manufacture is confirmed by the placement of the stamp, The marking is carried out by applying the imprint of a metal or elastic stamp directly to the received product, on the accompanying tag or on the accompanying acceptance documentation. The location of the stamp, the method of branding and the size of the imprint are determined by the design documentation in accordance with GOST 2.314-68. In this case, the marking is adhesive, i.e., the application of imprints with paint compositions.

9. Fluorescent control.

The luminescent method is one of the main capillary methods of non-destructive control. It is based on recording the contrast of the visible indicator pattern luminescing in long-wave ultraviolet radiation against the background of the surface of the control object.

The capillary method of flaw detection allows detecting microscopic surface defects on products from almost any structural materials. The method is based on capillary penetration of indicator liquids (penetrants) into the cavities of surface and through irregularities of the material of control objects and recording of generated indicator traces visually or using a transducer. In the luminescent method, a highly sensitive set of defectoscopic materials is used, which allows detecting surface defects with an opening of about 0.1 μm. It consists of permeant PLH6A, developer PR1, cleaner OZH1.

10. Coating - AN. OKS chrome/enamel EP140 bluish-gray 265 GOST 907377.

Protective coatings are used to protect the surfaces of the part from corrosion, that is, destruction processes as a result of chemical or electrochemical effects of the external environment, as well as to give the part an aesthetic appearance.

If the paint coating is preceded by a metal (inorganic) coating, then the designation is recorded by a fraction, the numerator of which indicates a metal or non-metallic (inorganic) coating according to GOST 9,073 - 77, and the denominator - paint.

The inscription in the numerator means that the surface of the part is subjected to a chromate coating, anodized.

Oxide film coating - oxidation - is used to protect steels, copper and aluminum alloys from atmospheric corrosion.

Oxidation of aluminum and its alloys, also called anodization, is carried out most often by electrochemical treatment in a solution of sulfuric acid, chromic or oxalic acid. By anodizing, the thickness of the oxide film, which is always present on the aluminum surface, can be increased tenfold. The obtained film has high hardness, heat resistance, electrical insulation properties, and adheres well to the surface of aluminum. Having significant porosity, the film is capable of being painted in various colors with organic and mineral dyes.

Chromium coatings are characterized by high hardness, low coefficient of friction, the ability to firmly adhere to the base metal, as well as good chemical and thermal resistance.

The inscription in the denominator means that all external surfaces must be covered with EP enamel - 140 bluish - gray; 265 is the number of the coating system.

Enamels are intended for painting pre-loaded surfaces from magnesium, aluminum and titanium alloys, as well as copper and its alloys.

Enamels are used to obtain upper layers of coatings according to the layer of primer or flooring. They shall provide the coating with the required colour, cover and durability under operating conditions.