Diploma project of the post of diagnostics of checkpoints and rear bridges of tractors

Contents

INTRODUCTION

1. ANALYSIS OF FARM OPERATION. PURPOSE AND OBJECTIVES OF THE WORK

1.1. Performance indicators

1.2. Logistics base of the economy

1.3. Production and territorial structure of the economy

1.4. Composition of the machine and tractor fleet

1.5. Analysis of Tractor Use

1.6. Rationale for the project theme

1.7. Purpose and objectives of thesis

2. JUSTIFICATIONS FOR DEVELOPMENT OF TRACTOR DIAGNOSTICS STATION

2.1. Basic concept of diagnostics

2.2. Fundamentals of non-disassembly technical diagnostics as a result of increased reliability of ICC

2.3. Requirements for technical diagnostics of vehicles and tractors during their development and operation

2.4. Effectiveness of organization of diagnostics in agricultural enterprises

3. DEVELOPMENT OF DIAGNOSTIC TECHNOLOGY

3.1 Organizational and technological principles of diagnostics

3.2 Diagnostic Technology

3.3. Process Site Layout

3.4. Calculation of post area

3.5. Calculation of the annual diagnostic program description of the technology

3.5.1 Calculation and selection of auxiliary equipment for diagnostic station

3.5.2. Organizational mode of operation of workers and equipment

4. DEVELOPMENT OF BENCH DESIGN

4.1 Description of the developed design of the diagnostic bench for checking the technical condition of boxes and driving bridges of tractors and trucks

4.2 Description and principle of diagnostic bench operation

4.3 Bench Operating Rules

4.4 Structural calculation of bench units and parts

4.4.2 We select a two-stage reduction gear box from the standard row according to the transmitted torque, force and frequency

4.5 Calculation of chain transmission

5. PROJECT FEASIBILITY STUDY

5.1 Determination of costs for manufacturing and upgrading the test bench for diagnostics of gearboxes and rear axles

5.2 Technical and Cost Effectiveness from Implementation of Diagnostic Bench

6. SAFETY AND ECOLOGY

6.1 Occupational Safety

6.1.1 Analysis of working conditions and safety

6.1.2 Organizational and legal issues

6.1.3 Production sanitation

6.1.4 Safety and fire prevention

Fire prevention

6.2 Emergency Safety

6.3 Ecology

CONCLUSION

LIST OF SOURCES USED

Applications

Summary

This diploma project proposes a project for the layout of a gearbox diagnostic post and driving bridges of vehicles with the development of a test bench for diagnostics.

The theoretical part describes the justification for the need to develop a diagnostic post for gearboxes and driving bridges using disassembly-free methods that reveal defects in these parts of the machine, as well as the requirement for technical diagnostics during operation. The effectiveness of the organization of diagnostics in agricultural enterprises is justified.

In the design part, the site for the diagnostic post was selected and there is a description of the diagnostic technology for driving bridges and transmissions of vehicles.

In the structural part, a bench is presented that allows analyzing the technical state of the vehicle transmission and determining its repairability, while calculating and selecting mechanisms for transmitting torque from the drum unit to the electric brake. Roadmap for drum shaft manufacturing has been developed.

The section on nature protection considers safety during diagnostic work, as well as calculations on exhaust gas removal from the repair shop, radioactive contamination of the area in case of radiation leakage at the Leningrad NPP, as well as calculation of the wastewater treatment and disposal system of the washing machine.

In the economic part, the economic effect of this project was calculated, as well as the payback period for capital investments.

The volume of the graphic part is made on 9 sheets.

The volume of the explanatory note is 94 sheets.

Introduction

It is especially necessary to determine the technical condition of the units when the unit or unit has failed. According to certain practically established signs, you can find an interface or node where operability is impaired. But this is an extreme case. It is desirable to anticipate the moment of failure in advance in order to exclude it.

Technical diagnostics of tractors and their separate units are aimed generally at solving one or several problems:

determination of technical condition (serviceable or faulty);

search and localization of fault or fault location;

prediction of residual resource or probability of failure-free operation at specified operating time intervals (mileage).

For successful implementation of these tasks, certain works are carried out to develop diagnostic support, improve control suitability and establish indicators and characteristics of diagnostic processes.

The most optimal solution is to carry out work on the diagnostic support of tractors at all stages, from their development to complete write-off, i.e. at the stages of development, production, operation, overhaul and storage, as well as when substantiating the certificate of write-off of specific tractors.

Diagnostic support is a set of interconnected diagnostic methods, standards, technical (hardware) and software tools, diagnostic processes, metrological support systems for used methods and technical diagnostic tools reflected in technical documentation.

Control suitability of tractors and their units is ensured at the stages of their development and manufacture by compliance with the requirements for technical diagnostics in terms of structural design of products, parameters and methods of diagnostics, and indicators of evaluation of object control suitability.

The purpose of the thesis is a project for the layout of a diagnostic post for gearbox and leading bridges of vehicles with the development of a stand for diagnostics at the Pushkinskoye agricultural farm.

1.5. Analysis of Tractor Use

In recent years, the Pushkinskoye farm has no money for fuel and lubricants, spare parts, etc. Agricultural production is not staffed. On 17 existing tractors of various brands, only 6 machine drivers. There are no mechanics for repair and maintenance of tractors, cars, agricultural machines, livestock equipment, etc. The equipment is not prepared for sowing. There is no repair schedule and maintenance. There is no technology for repair and maintenance of equipment. The farm is not fully mechanized potato harvesting, hay harvesting, labor-intensive processes on the livestock farm, etc. Production culture is low. There are no Job Instructions for agricultural works. At the same time, the economy has a good material and technical base. There are typical repair and mechanical workshops, car garage, machine yard, fuel and lubricants warehouse, parking areas, good livestock facilities, hay sheds, silo towers and trenches, etc.

Due to the not quite good financial and economic situation, the Pushkinskoye Machine and Tractor Fleet (ICC) is aging both physically and financially. Every year it decreases, however, the farm still has a fairly wide range of tractors, cars and agricultural machines, which are capable of performing a large range of various agricultural work. The average operating time for almost all machines exceeds 10 years.

Another reason for the decrease in the number of machine and tractor fleet is the weak repair base and the untimely allocation of funds for the purchase of spare parts. Due to the lack of personnel and the required amount of materials for the repair and maintenance service, no maintenance and maintenance measures of all electrical and thermal equipment are carried out for several years. Actual operation is performed in emergency mode ("for failure"), which is unacceptable for safe and trouble-free operation of plants. Therefore, with accurate forecasting of maintenance and repairs, the machine-tractor fleet can support the technological process of harvesting crops, harvesting feed, perform the existing amount of work on a livestock farm and carry out transport transportation without interruption.

1.6. Rationale for the project theme

An analysis of the machine and tractor fleet showed that the farm has problems with tractors in view of the fact that the tractor fleet is very worn out. Frequent breakdowns occur at field work due to poor equipment with equipment, problems arise with plowing, landing and cleaning of landings .

Therefore, in the farm, it is necessary to prevent in advance breakdowns of the main parts of tractors in order to prevent disruption of sowing and harvesting landings. This can be prevented if the tractor is diagnosed before leaving the territory. During pre-diploma practice, it was noticed that the gear often flies out, the engine is constantly overheated, noise and buzz in the rear axle increase .

The analysis showed that the main parts of tractors that account for more breakdowns are the gearbox and rear axles of tractors. Therefore, the farm needs to introduce a post and diagnostics of these main parts of the tractor.

1.7. Purpose and objectives of thesis

The purpose of the thesis is the design of the diagnostic post of the manual gearbox and the rear axle of MTZ82 tractors and other similar equipment with the development of a stand for diagnostics in the Pushkinskoye farm.

Thesis tasks:

analysis of existing equipment and selection of a site on the territory of the Pushkinsky farm for the gearbox and rear axle diagnostics post;

substantiation of the need to develop a diagnostic post;

development of diagnostic algorithm and layout of diagnostic station;

development of a stand for determination of operability, detection and localization of failure and malfunction of the diagnostic object;

carrying out a feasibility study for the implementation of this diagnostic system;

Assessment of environmental parameters and development of basic labour protection measures.

2. justifications for the need to develop a tractor diagnostic station

2.1. Basic concept of diagnostics

Diagnostics - the process of determining the technical condition of the machine or its individual units by non-disassembly methods. Diagnostics can be objective (carried out with the help of instrumentation, special equipment, devices, tools) and subjective carried out with the help of the sensory organs of the person checking and protozoa, technical means of the metroscope, dynamometer key, etc., which do not allow to quantify the technical state of the assembly unit, unit or machine as a whole. In practice, especially in small auto farms, often objective methods of diagnosis are combined with subjective ones, which cannot be considered quite reliable.

Instrumental diagnostic methods are more advanced and promising. They provide a quantitative assessment of the state of the inspected objects without disassembling them, which allows you to significantly reduce the cost of forces and funds for the maintenance and repair of cars, while the operation of assembly units and mechanisms is not disrupted. Any "disassembly - assembly" of the mechanism causes additional wear of parts, damage to gaskets and glands, violation of threaded connections and requires time. In addition, they allow you to most reliably predict the period of failure-free operation of an assembly unit, unit or machine as a whole.

Subjective (control and diagnostic) methods allow you to give an indicative assessment of the technical state of the objects of verification, without quantitative assessment. They are used, as a rule, for a preliminary diagnosis.

The most important characteristics of the car are subject to diagnosing: the developed or power consumption, speed of the movement, acceleration, the movement on inertia (run-down), fluctuations, vibrations, a way of braking, fuel consumption, etc .

Technical diagnostics is a field of science that studies and establishes signs of failures of machines and their mechanisms, developing methods and means by which a conclusion is made (diagnosis is made) about the nature and essence of malfunctions. Technical diagnostics determine the rational sequence of mechanism checks and, based on the study of the dynamics of the technical state parameters of the units and assembly units of the machine, solves issues of resource prediction and failure-free operation.

The practical purpose of technical diagnostics is to determine with minimal labor and time the technical condition and causes of failures of the car without disassembly and to provide recommendations for its maintenance and repair.

Depending on the results of these tasks, diagnostics provide practical recommendations that establish:

during maintenance - causes of failures; the need to adjust mechanisms or replace individual parts and mechanisms during the next periodic maintenance; the need to send the assembly units, units and machine as a whole to specialized repair facilities for major repairs or to workshops, to maintenance stations for ongoing repairs;

during current repair - list of parts and units to be replaced, as well as mechanisms to be adjusted;

Technical diagnostics operate on a number of special terms and concepts. The technical condition of the machine, unit or individual interface depends on the state of the elements (parts), of which the interface (mechanism) consists, the technical condition of the elements is determined (evaluated) by parameters .

The parameter is a physical quantity or function that characterizes the serviceability or serviceability of the diagnostic object and varies during operation. During technical diagnostics, the parameters of the technical condition of the mechanism are divided into structural and diagnostic.

The structural parameter is a physical quantity that directly characterizes the technical condition or operability of the mechanism (machine): geometric shape, dimensions, mutual arrangement and conjugation of parts, purity of their surface, microstructure of the material from which the parts are made, etc.

The structural parameter of the mechanism can be expressed in linear measures, in the size of the gap, in changing the tightness or strength of the joints, in changing the mass of the part, etc. They are generally not directly measurable without disassembling units and assemblies.

The diagnostic parameter is also a physical quantity, but controlled by diagnostic tools and indirectly characterizing the state or operability of the machine. The diagnostic parameter can characterize the technical condition of both individual couplings or mechanisms of the car, as well as some of their totality, depending on this it is called private or generalized.

Technical diagnostics when determining the technical condition and predicting the resource of the mechanism operate on several parameter values. Both structural and diagnostic parameters by their value (value) can be nominal, permissible, limit and current (at the time of diagnosis).

The nominal value of the parameter is the value of the parameter defined by its functional purpose and serves as the beginning of the deviation reference. The nominal value of the parameter is, as a rule, for new or overhauled units and units after their run-in and run-in.

The permissible parameter value is the boundary value of the parameter, at which the interface, assembly unit, mechanism is left without repair, adjustment or other preventive operation, ensuring reliable operation of the product until the next scheduled control. A number of basic parameters of machines and mechanisms can have two permissible values. One of them is calculated based on the need to ensure the failure-free operation of the mechanism until the next scheduled maintenance (usually up to to TO-2), and the second - before the next repair.

Diagnostics are carried out during maintenance, repair, identification of causes of failures, as well as when determining the residual life of machines.

The main purpose of diagnostics is to ensure the most efficient operation of machines at the minimum cost of their maintenance and repair. The reduction of costs in the implementation of diagnostics is achieved by performing repair and maintenance actions in accordance with the technical condition of the machines, which makes it possible to prevent premature work, prevent failures in a timely manner and reduce machine downtime for technical reasons.

During diagnostics, serviceability or only serviceability of mechanisms and systems, state of adjustable coupling, technical characteristics of components specified in the machine operating manual are determined; signs, places and causes of failures are detected. As a result of diagnostics, a characteristic of the actual technical condition of the machine is obtained (diagnosis is made). Based on the diagnosis, a prescription is drawn up that indicates the specific repair and maintenance effects necessary to restore the parameters of the technical condition that have exceeded the permissible limits.

The basis of the material base of diagnostics is made up of diagnostic sets of equipment, devices and devices, as well as diagnostic posts and areas at maintenance points (TSS), at central repair shops (CMM) of farms and at tractor maintenance stations (STOT).

Diagnostics are performed according to the technology containing technical requirements for diagnostics, instructions on the procedure and modes of work, equipment used, sequence of checks, operational standards of labor intensity and duration of work.

As a result of diagnostics, information about the technical condition of the machine is obtained, which allows timely detection and prevention of machine failures, maintaining optimal adjustments, reducing machine downtime due to technical malfunctions, skillfully assessing the technical condition of the machine components and developing recommendations for carrying out preventive operations. Replacement of individual parts of the machine, their repair or further operation without maintenance.

The introduction of diagnostics allows to organize their maintenance (maintenance) and repair on the basis of reliable information about the technical condition of the machines.

The economic effect of diagnostics is achieved by preventing premature maintenance work, timely detection and prevention of failures, establishing optimal terms for putting machines for repair, reducing machine downtime, reducing the consumption of operational materials and spare parts.

2.2. Fundamentals of non-disassembly technical diagnostics as a result of increased reliability of ICC

The reliability of the machine is laid down in the process of manufacture and repair, and maintaining it at a high level is the primary task of the operators.

The process of operation of the machine is accompanied by three periods:

1) run-in, or initial stage of work. Failures observed during this period can be explained by the fact that hidden defects, errors in assembly of units were made during manufacture or repair.

2) normal operation. This is the longest stage. The process of running-in is completed, and wear and aging are not yet manifested, failures are random. The task of the operators is to extend this period and minimize the number of failures.

3) aging. Even with careful design of components of any product, exemplary manufacture and careful operation, a period comes when failures occur more often - inevitable processes of wear and aging of the components of the machine affect.

The period of operation and its conditions have a significant impact on reliability indicators and can negate all the achievements of designers and technologists. In this regard, the implementation of operational measures that increase the pre-repair and inter-repair life of machines should be given great attention.

Running in new or repaired machines in farms actually lays the foundations of long-term and trouble-free work. It should be carried out in accordance with the recommendations of manufacturers or repair enterprises.

The normal operation of the machine has a great influence on reliability. Overload of the machine by load and speed, incorrect adjustment of clearances in bearings, gears and other connections cause violation of the temperature mode of operation of friction surfaces of parts, lubrication conditions, which leads to forced wear.

The organization of diagnostic work and the creation of the necessary base for its implementation are the main condition for ensuring reliable and economical operation of the machine and tractor fleet. The most high efficiency of using the machine-tractor fleet and ensuring its reliable work was achieved by farms in which stationary diagnostic points were organized, links were created for master adjustment officers and the necessary washing, lubrication, adjustment, diagnostic equipment, devices and equipment, and mechanization tools were widely used.

The receipt for repair of machines with an unused resource can be explained by the lack in most farms of the necessary technical means for an objective assessment of the condition of tractors and combines without disassembling them, that is, a non-disassembly technical diagnostics service.

Non-disassembly technical diagnostics help to identify additional reserves in the use of the machine and tractor fleet that do not require significant investments.

Specialists of leading foreign companies producing machines and diagnostic tools believe that the field of maintenance is sharply lagging behind the field of machine production. They consider diagnosis as one, but a means of bringing together the levels of development of these two areas.

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