Diploma "DESIGN OF SECTION FOR MANUFACTURING PART" SHAFT-GEAR "TWO-STAGE REDUCTION GEAR"

Contents

CONTENTS

INTRODUCTION

1. DETAIL DRAWING

1.1. Part Service Assignment, Classification, Design

1.2. Part Surface Classification, Constructability Analysis

1.3. Review technical requirements and how to achieve them

2. DEFINITION OF PRODUCTION TYPE

2.1.Define Transaction Fixing Factor

2.2. Definition of operating lot

3. SELECTION OF PROCUREMENT METHOD

3.1. Comparative analysis of the basic and proposed methods of obtaining the workpiece

3.2. Business case for the proposed procurement method

4. DEVELOPMENT OF ROUTE PROCESS

4.1. Develop Surface Route

4.2 Justifications of the list of process operations

4.3 Selection of equipment and cutting tool by operations

4.4 Selection of process route option according to reduced cost minimum

4.5. Operating Process Record

5. DEVELOPMENT OF OPERATIONAL PROCESS

5.1 Rationale for selection of process bases and designation of operational dimensions

5.2 Calculation of coordinates of reference points:

5.3 Selection of measuring tool and instrumentation by operations

5.5 Calculation of cutting modes and main process time

6. PROCESS TOOLING DESIGN

6.1 Design of special installation and clamping device for milling and centering operation

6.2 Design Tool for Milling Operation

6.3 Design of control accessory

7. MECHANICAL SECTION DESIGN

7.1 Establishment of operating mode and annual time fund of workers and equipment

7.2 Determination of quantity of main production equipment

7.3 Determination of the number of employees of the site

7.4 Area of the site

7.5 Design of Support Offices

7.6 Section Layout

7.7 Site Equipment Layout

7.8 Lifting and transportation equipment, in-house and inter-operational transport

8. ORGANIZATION AND MANAGEMENT OF PRODUCTION ON SITE

9. CALCULATION OF TECHNICAL AND ECONOMIC PARAMETERS OF THE DESIGNED AREA

9.1. Calculation of the required quantity of equipment and its loading

9.2. Calculation of the required number of employees

9.3. Calculation of capital investments

10. SAFETY OF LIFE

10.1 Lighting calculation

10.2 Microclimate

10.3 Harmful substances

10.4 Noise

10.5 Electrical Safety

10.6 Fire Safety

11 ECOLOGY

11.1. Sources of chip formation and SOTS

11.2. Wastewater treatment

LIST OF LITERATURE

APPLICATION

APPLICATION

Introduction

In this diploma project, a machining section of the shaft-gear with an annual output volume of NG = 9800 pieces is being developed.

The design is based on the process of making a shaft using CNC machines.

When designing the production process in the mechanical workshop, special attention will be paid to the interconnection of the stages that result in the finished product, quantitative and qualitative changes in the production facility, as well as the main and auxiliary production systems and a set of iterations in the design.

It is better to use NC machines for batch production conditions.

The technological capabilities of CNC machines are due to their versatility, increased rigidity, drive power and accuracy, a lot of instrumentation, automation of the cycle of technological operations, a wide range of spindle and feed speeds, the presence of tool position correctors, the possibility of manual correction of feeds, interpolation modes, reduction of auxiliary time due to high speeds of auxiliary moves and low tool change time.

The use of CNC machines instead of universal equipment has significant features and creates certain advantages, in particular: reduction of production preparation time by 5070%; reduction of the total production cycle by 5060%; savings of 3085% on engineering and manufacturing of technological equipment; increase of labor productivity due to reduction of auxiliary and main processing time on machine.

Part Drawing

Part Service Assignment, Classification, Design

The Valshesternya part is part of a cylindrical two-stage reduction gear and serves to transfer torque from a high-speed drive shaft to a slow-speed driven shaft.

Reduction gear - a mechanism used to reduce or increase the speed and increase or decrease the torque, respectively. This is a complete mechanism connected to the engine and the working unit by clutches or other detachable devices.

Gear or worm wheels fixed on shafts are arranged in reduction gear case. Shafts are supported by bearings, which are located in the gearbox housing in special mounting slots; rolling bearings are mainly used.

Cylindrical reduction gears are equipped only with cylindrical gears and differ in the number of stages and the position of the shafts. Cylindrical two-stage gearboxes are typically arranged in an expanded, bifurcated or coaxial pattern with one, two or three power streams. The most common is the expanded schema. Gearboxes made according to this scheme are very technological, have a small width, allow for easy and rational unification.

Review technical requirements and how to achieve them

According to the specifications for the manufacture of shafts, the diameters of the landing necks are held according to 2-3em, and in some cases according to the 1st accuracy class. The ovality and conicity of necks does not exceed 0.2÷0.4 of admission on their diameter. The beating of the landing necks relative to the basements should not exceed 10? 20 μm. Axial run-out of thrust ends must not be more than 10 mcm at the greatest radius. The non-parallelism of the key grooves should not exceed 0.1 μm per 1 mm of the tolerance length for the length of the feet 50? 200 μm, the permissible curvature of the shaft axis 0.03? 0.05 mm/m.

The use of permanent process bases (center holes) makes it possible to increase accuracy and reduce the labor intensity of processing coaxial stepped surfaces.

Lengthwise dimensioning facilitates machine adjustment and reduces processing labor.

Ecology

Sources of chip formation and SOTS

The following metal cutting machines are located on the designed mechanical section for the production of the Valschestern part of the two-stage reduction gear: milling centering semi-machine MP71M, lathe with CNC 16K20F3, toothfreather semi-machine 53A20, splitfreather semi-machine 5350 and round grinding 3M151F2. To reduce temperatures in the cutting zone and reduce loads, water and oil based LFFs are used, for which certain disposal methods are required. Also, various tools are used in the processing of the part: cutters, drills, cutters, grinding wheels. During machining, a large amount of metal chips is formed, and during grinding operations, dust is formed consisting of small parts of metal, abrasive and binder. This dust negatively affects the working capacity and health of workers. Therefore, equipment for grinding operations should be located in a room separate from other machines, equipped with good ventilation. According to Federal Law of the Russian Federation No. 89 "On Production Waste and Consumption," in order to protect the environment from harmful production factors, it is necessary to switch to low-waste and, if possible, waste-free technologies and industries.

Types of wastes and their disposal during operation of the site:

Chips of ferrous metals - formed during mechanical blade processing of metals. The amount of chips during the production of the gear shaft for 1 year is 43512 kg. The chip material of 40X steel is well recyclable. The place of temporary accumulation is wooden boxes in the workshop, as the waste is accumulated, it is handed over to AHO, which has a site in the storage area for accumulation of scrap metal. Metal containers for accumulation of scrap and chips, separately for ferrous and non-ferrous metals, are installed on the site. Scrap, as it accumulates, is delivered to the procurement production for remelting as a raw material for the production of blanks.

LMS wastes (lubricating and cooling process media) - are generated as a result of maintenance of machine lubrication and cooling systems. The SMS is handed over to the AHO, which has an organized storage place - a tank, in the storage area in the territory.

The waste oil is industrial, formed during the current and periodic technological maintenance of the machines and from the quench bath in the thermal section. Withdrawal

is collected in a metal container and handed over to an AHO having tanks for collecting petroleum products at a separate site of fuel and lubricants in the storage area. Currently accumulating in the territory of the landfill of the enterprise due to the lack of a place for receiving spent petroleum products.

Wet rags - formed as a result of maintenance of equipment in need of lubrication during scheduled and ongoing repair work. It is collected in places of temporary accumulation, after which it is burned in the boiler room.

Scrap of abrasive products and worn out abrasive wheels - formed during the operation of grinding and grinding machines, collected in a portable box, waste is taken to landfill or used by employees of the enterprise.

Diamond circles and mandrels, fully spent and worn circles and mandrels are manually removed from the workshop to the storage site in the storage area, then waste having metal bases is handed over to Vtormet, the rest, together with garbage, is taken to landfill.

Production garbage - formed as a result of the production activity of the workshop, is a mixture of various materials in the form of sawdust, shavings of estimates from the floors, etc., collected in a metal box in the workshop, currently together with household garbage, taken to landfill.

Oil sawdust - formed during cleaning of the floor from oil leaks near the machines, collected in a metal box in the workshop, as they accumulate, they are handed over to the AHO site, from where they are taken for combustion to the boiler room.

Waste from quench baths - slags, carburezer, etc., is formed during the annual cleaning of quench baths in the thermal area, manually removed from the workshop to the storage site in the zone, then taken to landfill together with garbage.

Dust from grinding, grinding and polishing machines is removed by local suction; cyclone of TsN15 type is installed on grinding machines of tool shop.

Wastewater treatment

Waste water is also generated in the mechanical area in addition to various types of waste. Waste water in production is generated as a result of cleaning of production premises upon completion of work, as well as in the process of washing parts for removal of oil residues and SOTS. MOS clean rooms from chips located on the floor, as well as SOTS. As a result, wastewater treatment is necessary to reduce the concentration of pollutants.

When choosing a waste water treatment method and the necessary technological equipment for this, it must be taken into account that the specified efficiency and reliability of any treatment device are provided in a certain range of concentrations and impurities and waste water flow rates. Most machine-building plants are characterized by constant consumption and composition of wastewater, but in some technological processes there are short-term changes, which can significantly reduce the efficiency of treatment devices or disable them. For example, volley discharges of spent process solutions in thermal, etching and electroplating shops cause a significant increase in the concentration of heavy metals in waste water at the outlet to the treatment facilities. The rapid melting of snow, as well as intense rains, cause a significant increase in the flow of surface wastewater at the outlet to the treatment facilities.

To ensure normal operation of treatment facilities in these cases, it is necessary to average the concentration of impurities or waste water consumption, and in some cases for both indicators simultaneously. To this end, an averager is installed at the entrance to the treatment facilities, the selection and calculation of which are determined by the characteristics of salvo discharges.

Treatment of waste water from solid particles depending on its properties, concentration and fractional composition at machine-building enterprises is carried out by methods of cleaning, settling, separation of solid particles in the field of action of centrifugal forces and filtration.

Filtration is the primary stage of wastewater treatment. Designed to extract large insoluble impurities up to 25 mm in size from waste water, as well as smaller fibrous contaminants, which in the process of further treatment of effluents prevent normal operation of treatment equipment.

Settling - based on the features of the solid particle deposition process in the liquid. There may be free deposition of non-adhering particles that retain their shapes and sizes, and precipitation of particles that tend to coagulate and change their shape and dimensions. The patterns of free deposition of particles are practically preserved at a volume concentration of precipitated particles up to 1%, which corresponds to their mass concentration of no more than 2.6 kg/m3.

Separation of solid impurities in the field of action of centrifugal forces is carried out in open or pressure hydrocyclones and centrifuges.

Filtration of waste water is intended for their purification from fine solid impurities with a small concentration. The filtration process is also applied after physicochemical and biological purification methods, since some of these methods are accompanied by the release of mechanical impurities into the liquid being cleaned.

For the treatment of waste water of machine-building enterprises, 2 classes of filters are used: granular, in which the treated liquid is passed through nozzles of unrelated porous materials, and microfilters, filter elements that are made of bonded porous materials.

Treatment of waste water from oil products depending on their composition and concentration is carried out at machine-building enterprises by settling, treatment in hydrocyclones, flotation and filtration.

Settling is based on the patterns of surfacing of oil products in water according to the same laws as precipitation of solid particles. The settling process is carried out in settling tanks and oil traps. In the design of treatment facilities, the use of settling tanks is envisaged, both for the deposition of solid particles and for the surfacing of oil products. Settling tanks are used to extract insoluble precipitating or popping mechanical contaminants (emulsified oils, petroleum products, etc.) from waste water. In the direction of waste water movement in the settling tanks, they are divided into horizontal, vertical, radial and combined.

Separation of oil products in field of action of centrifugal forces is performed in pressure hydrocyclones. At the same time, it is more advisable to use a pressure hydrocyclone for the simultaneous extraction of both solid particles and oil products, which must be taken into account in the design of the hydrocyclone.

Treatment of waste water from impurities by flotation consists in intensification and intensification of process of oil products surfacing when their particles are enveloped with bubbles of air supplied to waste water. This process is based on the molecular adhesion of oil particles and bubbles of air finely dispersed in water .

Depending on the method of air bubble formation, several types of flotation are distinguished: pressure, pneumatic, foam, chemical, biological, electrophlotation, etc.

Conclusion

The proposed methods of air treatment in the working zone, waste water and disposal of industrial waste make it possible to minimize the harmful impact of production factors on the environment. The reuse of chips and regenerated SOTS also increases the environmental efficiency of the project.