Operation of road transport enterprise

Summary

In this diploma project, the work of the motor transport enterprise Avtopark LLP was considered and calculations were made on the technological design and organization of the work of the TO-1 zone with a proposal to increase its production capacity.

The project consists of several parts that address issues relevant to each area that are directly related to the work of the ATP.

The calculations are aimed at improving the operation of ATP taking into account the current changes and trends in the automotive industry, at adapting the enterprise to market conditions, the feasibility of which is justified in the economic part of the project.

Attention is paid to occupational safety issues, which determine ways to solve safety problems during work and methods of determining engine toxicity.

In the design part of the project, an analysis of existing solidifier models was carried out and economically feasible changes were made to the design of the selected model.

In the last part of the project, the cost-effectiveness calculation is performed, where the cost-profit ratios are determined.

The diploma project is executed in the volume of 104 sheets of the explanatory note and contains 10 sheets of graphic material .

Introduction

The purpose of road transport, as part of the transport complex of the country, is to meet the need of agriculture and the population of the country for freight transport at the minimum cost of all types of resources. This general objective is achieved as a result of improved road transport efficiency: increased transport capacity and vehicle productivity; reducing the cost of transportation; increase staff productivity; ensuring environmental friendliness of the transport process.

Technical operation as a subsystem of road transport should contribute to the realization of the goals of agribusiness road transport and have controlled indicators of the efficiency of the system, that is, agribusiness road transport.

Knowledge of quantitative and qualitative characteristics of regularities of changing parameters of technical condition of units, units and the car as a whole allows controlling the operability and technical condition of the car during operation, i.e. maintaining and restoring its operability.

The need to maintain a high level of operability requires that most of the faults are prevented, that is, the product is restored to health before a fault occurs. Therefore, the task of maintenance is mainly to prevent the occurrence of failures and faults, and repair - to eliminate them.

The vehicle maintenance and repair system is subject to the following requirements:

Ensuring the specified levels of operational reliability of the automobile fleet at rational material and labor costs;

Resource-saving and environmental focus;

Planned and normative nature, allowing to plan and organize maintenance and repair at all levels;

Mandatory for all organizations and enterprises that own road transport, regardless of their departmental subordination;

Specificity, accessibility and suitability for leadership and decision-making by all sections of the Road Transport Engineering Service;

Stability of the basic principles and flexibility of specific standards that take into account changes in the operating conditions, design and reliability of cars, as well as the economic mechanism;

Taking into account the variety of operating conditions of cars.

Ensuring the required level of technical readiness of rolling stock for transportation at the lowest labor and material costs is the main requirement of the production and technical base of road transport of the agro-industrial system.

The level of development of PTB has a significant impact on the performance of ATP, and therefore on the entire process of maintenance and repair. The quality of the TEA works is directly related to the level of development of PTB. The technical readiness of the vehicle fleet and its reliability, productivity will increase with an increase in indicators and the development of PTB. One of the main goals of the maintenance and repair system is the quality of the work, reliability, the level of equipment of the workplace and the post. Paying special attention to the development of PTB in the environment of the material and technical base is now more relevant than ever for the road transport of our country. The continuous development of the automotive industry of foreign countries only reinforces the need to develop the material and technical base of road transport of our republic.

The importance of road transport as an element of the country's agricultural production infrastructure is determined not only by the fact that no economic activity is carried out without its participation, but also by the fact that more than 80% of all goods delivered by all modes of transport are transported to them. Cars carry out either the entire process of transporting goods from manufacturer to consumer, or, in cooperation with other modes of transport, carry out its initial, intermediate or final phase.

Road transport is of great importance for the life of the population of the country, both in cities and in rural areas. It contributes to the growth of the life of the people economically and culturally, to the equalization of the living conditions of the population.

Principles and

methods of enterprise management

Enterprise management is a complex process. It should ensure the unity of action and focus of the work of the teams of all divisions of the enterprise, the effective use of various technologies in the labor process, and the interconnected coordinated activities of the workers. From which management is defined as a process of targeted impact on production to ensure its effective implementation.

The enterprise is a complex system. Any system has a controlled and controlling system. The first consists of a number of interconnected production complexes: main and auxiliary workshops, various kinds of services. The second is a set of controls. Both systems are connected by means of information coming from control objects, as well as from external sources of information to the control system, and decisions taken on the basis of this information, which in the form of commands are sent to the controlled system for execution.

The proportional ratio of individual parts of the system is the main requirement for its functioning. However, each system is not stable once and for all. It develops, changes, improves. At the same time, the impact on the enterprise is possible not only on the part of the system, but also on the part of other systems.

The production process and its peculiarities necessitate the establishment of appropriate forms and management functions. Production management can be represented schematically in a number of main steps, covering the collection of the necessary initial information, its transfer to the heads of the relevant departments, its processing and analysis, the development of decisions and, finally, the analysis of the results of the performed

Methods for testing the toxicity of gasoline engines

As has already been noted, many production processes in motor vehicles are accompanied by the release into the air of toxic substances that have a harmful effect on the human body, and these, of course, include gasoline, which is widely used in road transport as the main type of fuel.

Harmful substances in chemical composition can be general toxic, irritating, carcinogenic, mutagenic. They penetrate the body through the respiratory organs, digestive system and skin.

Biological (toxic substances) by their effect on the human body are conditionally divided into cauterizing effects acting on the respiratory organs, acting on the blood, acting on the nervous system, enzymatic and metabolic (antiplasmic) poisons.

Psychophysiological harmful production factors are divided into physical and neuropsychiatric overloads.

It has been proved that neuropsychiatric overloads occur due to over-voltage of analyzers, mental or emotional over-voltage and monotony of labor.

The most common toxic substances found in road transport are lead, tetraethyl lead, leaded gasoline, CO carbon monoxide, acrolein, nitrogen oxides, benzene, chromic acid, caustic alkali, acetone, cooling liquid, methanol, lubricating oils, epoxy resins.

Lead in motor vehicles is used in the soldering of radiators and gas tanks, as well as in the manufacture and repair of battery plates. Lead poisoning is detected only in chronic form when the complexion becomes pale gray (lead) due to anemia of vascular spasm. Sanitary supervision authorities prohibit the manufacture of lead whitewash, lead gaskets in the production of fillers, the use of glazes containing lead compounds. In battery departments, the work of adolescents, as well as the work of women, is prohibited. People with blood diseases are not accepted for work.

Tetraethyl lead - the strongest and most dangerous poison - is not used in pure form, but is used in ethyl liquid. Ethyl liquid is an antidetonator. It is also used in leaded gasoline.

Tetraethyl lead in ethyl liquid and in leaded gasoline completely preserves toxic and physicochemical properties. Tetraethyl lead quickly enters the body through the airways and skin.

Leaded gasoline causes the same poisoning as tetraethyl lead. Leaded gasoline can be poisoned by inhaling its vapors, contaminating its body, clothes, ingesting it with food or drinking water. Leaded gasoline, penetrating the blood, causes a general health disorder - a person is losing weight, the nervous system is disrupted. Signs of acute poisoning with leaded gasoline are detected after several hours or days. When gasoline is repeatedly received in small quantities, chronic poisoning occurs.

Carbon monoxide CO is a colorless gas without taste and smell, extremely poisonous. It burns with a bluish flame. Molar weight 28 kg/mol; density - 1.25 kg/m ³. A mixture of two volumes of CO and one volume of O2 explodes upon ignition.

Carbon monoxide, entering the human body, forms carboxyhemoglobin, which is not capable of oxygen transfer, as a result of which oxygen starvation occurs. Acute poisoning is observed when inhaling air with a concentration of carbon monoxide of more than 2500 mg/m ³ or staying in an environment with a concentration of CO 1800 mg/m ³ for 1 hour. The consequences of the poisoning may be a violation of the central nervous system, memory disorders, attention, functional neuroses, paralysis, hemorrhage in the retina. Loss of consciousness occurs when working for a long time in a room with a CO content of 650 mg/m ³. high concentrations of CO in the air are life-threatening. Chronic poisoning is caused by low concentrations with frequent and prolonged inhalation of carbon monoxide. Signs of chronic poisoning can be headaches, dizziness, insomnia, lethargy, flickering, twofold in the eyes, disorder in memory, drowsiness.

Acrolein (akroleinovy aldehyde - CH2CHCHO) comes to air of production premises of the motor transportation enterprises together with the fulfilled gases during the operation of engines on a heavy type of fuel. Acrolein is a colorless liquid with an acute irritating smell of burnt fats. Boiling point 52.4 ° C, density at 20 ° C - 0.841 g/cm ³, vapor density relative to air - 1.9; the odor perception threshold is about 4 mg/m ³. acrolein causes severe irritation of the upper respiratory tract, sharp inflammation of the mucous membranes of the eyes, in addition, there can be dizziness, flashes of blood to the head. The human body can transfer the concentration of acrolein in 7 mg/m ³ for no more than 1 minute.

Measures to combat the release of acrolein - the use of conveyors and electric cars for transporting cars in the areas of their maintenance, the use of local exhaust ventilation.

Nitrogen oxides are also contained in exhaust gases. Oxides and nitrogen dioxide are found in the largest amount. They enter the body through the upper respiratory tract. Symptoms of poisoning appear only after 6 hours in the form of coughing, shortness of breath, suffocation, pulmonary edema is possible. In blood, nitrites and nitrates convert oxyhemoglobin into metagemoglobin. Chronic poisoning is possible, accompanied by chest pain, cough, heart pain and headaches.

In the premises of Avtopark LLP, as in all motor transport enterprises, local and common ventilation is used to create clean air.

Benzene (C6H6) is used as fuel for automobiles in admixture with gasoline of not more than 25% by volume. When using benzene, acute and chronic poisoning is possible. Chronic benzene poisoning is characterized by a change in the vascular walls and damage to the hematopoietic function of the bone marrow. In the initial stage of chronic poisoning, patients complain of headaches and dizziness, fatigue, drowsiness, irritability, general malaise, and sometimes dermatitis or eczema appear on the skin of the hands. Acute poisoning is accompanied by dizziness, tinnitus, muscle weakness, feeling intoxicated.

It is allowed to store benzene only in metal and hermetically closed containers in warehouses equipped with ventilation and in open areas under a canopy. The preparation of the benzinobenzene mixture is allowed only by a mechanized method, and at outdoor temperature above + 4 ° C, benzene with gasoline is mixed in the open air. It is strictly forbidden to suck benzene with your mouth. For siphoning, workers are provided with pumps-siphons with hoses.

Gasoline vapors have a harmful effect on the central nervous system. There may be acute and chronic poisoning. With a severe degree and acute poisoning, there is a loss of consciousness, reflex arrest of breathing, seizures, trembling of the limbs, cough with sputum. A chronic form of poisoning is accompanied by neurasthenia, vegetoneurosis.

Caustic alkalis - caustic soda (NaOH) and caustic feces (KOH) are used in degreasing and washing automotive parts. Caustic soda and caustic feces act in a cauterizing manner, a scab forms on the skin, under which alkali penetrates into the interior of the tissue. With prolonged work and non-compliance with safety regulations, dermatitis, softening and rejection of the cornea, the appearance of cracks and dry skin can be observed. To avoid damage to the skin, it is necessary to introduce mechanization and sealing of the process. Analogous to the action of caustic alkalis, soda ash (NaCO3) acts, but is much weaker than other alkalis.

In order to prevent hands from drying out, the skin is lubricated with a burning ointment before work, after work is completed, hands are washed with warm water with soap.

Acetone (CH3COCH3) is a colorless liquid with an ether smell. It has narcotic properties and causes skin irritation. With acetone poisoning, headache, dizziness, general weakness, and a state of mild intoxication occur.

An effective ventilation device is a precaution against acetone exposure.

Cooling fluid is a special ethylene glycol low-freezing liquid poured into the cooling system of the car during its operation in the winter.

Ethylene glycol (CH2OH - CH2OH) and its aqueous solutions are extremely poisonous. It affects the central nervous system and human kidneys. Accidental ingestion of even a small amount of coolant can lead to death.

To prevent cooling liquid poisoning, the general safety requirements are strictly observed. The use of liquid is allowed only for the intended purpose. Its transportation and storage is carried out in serviceable metal bidions with hermetic covers of barrels with screwing plugs, which have devices for strengthening the seal. Containers for cooling liquid are thoroughly cleaned from solid precipitates, deposits and rust, washed with alkaline solution and steamed.

After working with a cooling liquid, especially before meals, hands with soap are washed to prevent ingress of ethylene glycol mixtures.

Personnel engaged in works using cooling fluid are allowed to work only after familiarization with the rules of its application.

Methods of toxicity testing. Used in engines as fuel, gasoline, combustion, is released into the atmosphere in the form of exhaust gases that pose a danger to human health. The problem is the incomplete combustion of the combustible mixture in the combustion chamber of the engine, due to which the unburned part is released into the atmosphere, the composition of which is a danger to humans and the environment.

The completeness of combustion of the fuel mixture in the engine is determined by experimental methods by a complete analysis of the composition of the exhaust gases. The current analysis methods allow a very accurate quantification of the components contained in the exhaust gases, including toxic ones.

In particular, in recent years, the method of analyzing the exhaust gases of cars, which has long been used in tests of internal combustion engines, has been widely used.

From the data on the quantity of exhaust gases, a number of valuable information about the engine operation can be obtained, in particular:

to determine the final results of the combustion process, as well as to determine the degree of completeness of combustion due to physical and chemical factors;

Evaluate the quality of the blending and gas exchange processes;

to determine the influence of various factors on the combustion process in order to effectively affect its individual stages.

Knowing the quantitative composition of the combustion products, it is possible to determine:

excess air ratio;

quantitative and qualitative difference of mixture in individual cylinders of a multi-cylinder engine;

the nature of the combustion process;

energy loss in the case of incomplete or poor-quality combustion;

The degree of toxicity of the exhaust gases.

The presence in the exhaust gases of unburned compounds such as: carbon monoxide CO, hydrogen H2, methane CH4, CH hydrocarbons or elemental carbon C2 as carbon black is evidence of incomplete combustion. The presence of combustible gas mixtures CO, H2, CH indicates poor-quality combustion. Combustion is considered incomplete if solid substances - soot and unburned hydrocarbons are present in the exhaust gases.

There are many analysis methods available to quantify the composition of gas mixtures. In this work, only methods that have been widely used are considered.

For the analysis of exhaust gases, methods based on the use of the chemical properties of individual substances included in gas mixtures are used. Chemical methods of analysis include the Ors method and the calorimetric method. Physical methods include methods based on the use of the physical properties of the investigated components:

absorption ( absorption) of infrared or ultraviolet radiation by the analysed medium;

heat conductivity of gases, magnetic susceptibility of oxygen to other gases;

ionization during combustion of hydrocarbons in the flame of a hydrogen burner.

An analytical method of gas chromatography is also known, based on the use of various absorption (sorption) and evaporation (desorption) properties of the column aggregate (sorbent) of individual components contained in the carrier gas passing through the column.

The measuring instruments used for the analysis of exhaust gases can be divided from the point of view of gas sampling:

Instruments for periodic or continuous measurements of gas components entering the instrument directly;

devices for periodic measurements of components of gases supplied to the device from tanks previously filled with exhaust gases.

Instruments for direct measurements are more convenient from the point of view of the practice of motor research. The exhaust gas sample is continuously introduced into the analyzing system directly from the exhaust pipe of the operating engine. The time required to determine the percentage of the measured component is from 310 s. The only disadvantage of this type of devices is that with their help only one of the components of the gas mixture can be determined.

Previously, the Ors chemical method, carried out by means of an analyzer of the same name, was used as a method for analyzing engine exhaust gases. The Ors method is as follows. A certain amount of exhaust gas sequentially passes through chambers filled with chemical reagents selected so that each of them absorbs one of the components of the exhaust gas. Based on the difference in the volumes of the exhaust gas sample before and after absorption, the volume content of the analysed component is determined.

Currently, this method is not used, since it is very time consuming.

1. Absorption spectrophotometry method - colorimetry. These methods are optical methods based on the application of electromagnetic radiation to the test sample. The most common methods are absorption spectrophotometry of visible, ultraviolet and infrared radiation. These methods use electromagnetic radiation with wavelength: the visible region of the spectrum 4 * 10... 8 * 10 cm, the ultraviolet region of the spectrum 1 * 10... 4 * 10 cm, the infrared region of the spectrum 8 * 10... 3 * 10 cm.

All methods of absorption spectrophotometry are based on measuring the absorption (absorption) of electromagnetic radiation with a certain wavelength of the medium under investigation.

The maximum absorption corresponding to a certain wavelength and the type of absorption curve depend on the structure of the molecule. They are its specific characteristic and can serve to identify a molecule.

In order to use the absorption phenomenon for the analysis of exhaust gases, it is necessary to study the relationship between the concentration of the substance in the solution and the radiation absorbed by this solution.

The most commonly used method of colorimetric measurements is the reference - analytical curve method. It consists in determining the dependencies between the concentration (within the established limits) of the colored substance in the solution and the amount of radiation absorption.

Spectrophotometry in the visible spectrum - colorimetry. An important feature of the absorption of radiation in the visible region of the spectrum is the possibility of visual observation of the phenomenon. This feature was used in the development of a method for determining nitrogen oxides in exhaust gases. To exclude the dependence of the assessment on the individual properties of the human eye, photocells and photocells are used in devices for measuring radiation intensity, with the help of which an objective assessment is made. Essence of colorimetric method lies in selective effect of reacting substance on desired substance. As a result of this action, a colored product is obtained.

Spectrophotometry in the ultra violet region of the spectrum. The spectrum of the spectrophotometer and ultraviolet radiation is basically the same as those used in the visible radiation range. It consists of a source of ultraviolet radiation, which is most often a hydrogen lamp, a light decomposition system (quartz prism or diffraction grating), an adjustable window, chambers with a reference gas and an analysed gas, a detector, which usually uses photocells sensitive to ultraviolet radiation, and a measuring electrical system acting on the principle of compensation.

Infrared spectrophotometry. The optical system of the infrared spectrophotometer is identical to the circuits of the above-described devices. The difference concerns the quality of the design features of individual parts of instruments.

the infrared source is typically an electrically discharged fiber of an agglomerated mixture of cerium, thorium, zirconium and yttrium oxides. Photocells or photocells cannot be used to detect infrared radiation because they do not respond to a given radiation region.

Thermocouples and sensitive diaphragm capacitors are used here. Given the complexity of the spectral pattern of infrared absorption, automatic spectrum registration and a two-beam system have been used in these devices earlier than in others, thereby eliminating not only the registration of the gas carrier spectrum, but also peaks created, for example, by carbon dioxide present in the air through which the instrument beam passes.

2. Gas chromatography method. Gas chromatography was used in the analysis of exhaust gases to determine hydrocarbons. The method of gas chromatography is based on the use of adsorption of gases and vapors to a solid carrier - sorbent (solid phase - gas) or liquid-gas equilibrium system, the liquid being stationary as a result of its deposition as a very thin layer on a solid sorbent. In gas chromatography, a sample of the test mixture of gases or vapors is introduced into a gas carrier passing through the column, which is a scavenging agent. At the outlet of the column, a mixture of the carrier gas and the analyte is obtained.

3. Chemiluminescent method. The concentration of nitrogen oxides in the exhaust gases of engines shall be determined by measuring the amount of NO and NO or by measuring the sum of NO + NO2 of the NOx to be designated. It was found that when analyzing the exhaust gases obtained as a result of combustion of poor mixtures in an infrared analyser, NO in a gas sample is quickly oxidized to NO2. Therefore, in the case where oxidation in the sample to be analyzed occurs in one analyser vessel, double analysis is required. In addition, taking into account the presence of CO2, Odva, CO, SO2 and water vapor in the exhaust gases, measurements should be carried out selectively.

Currently, the following main methods for determining nitrogen oxides in exhaust gases are used: Salzman chemical colorimetric method, mass spectrometry, absorption of ultraviolet radiation - on a non-dispersive analyzer, gas chromatography, absorption of infrared radiation - on a non-dispersive analyzer chemiluminescent method.

4. Instruments for continuous analysis of exhaust gases. Samplers and probes for exhaust gas sampling. Exhaust gases are continuously supplied from the engine exhaust system with a precisely determined intensity provided by special disk pumps.

Gas samples entering the analyzer during the passage through the vents are cleaned in ceramic filters from mechanical contaminants and dewatered.

When assessing the toxicity of an automobile or in studies to determine the causes of the formation of toxic components during the combustion of fuel in the engine, samples are taken from the exhaust pipe or directly from the engine cylinder. Regardless of the sampling location, the sampling device shall ensure that the sample composition is representative under these engine operating conditions. It is also necessary to keep the original sample composition until it is introduced into the analyzer, preventing air from entering the sample during its withdrawal.

In addition, normal operating conditions for the analyzers and the engine exhaust system shall be ensured.

Instruments for continuous analysis of exhaust gases. In order to fully assess the accuracy of engine exhaust gases, it is necessary, as noted above, to determine the content of components such as CO, NOx, SenNam, benzpyrene, carbon black, lead and sulfur compounds, as well as to determine the smell and degree of smokiness. We shall limit ourselves to a short review of typical analysers for the determination of individual toxic components in a continuous manner to the recommended engine test standards for exhaust toxicity.

Currently, gas analyzers based on the principle of spectrophotometry are widely used. Analyzers of this type allow fast, accurate and continuous analysis of engine exhaust gases.

The main manufacturers of such analyzers are Horiba (Japan), Beckman (USA), HartmanBrown (Germany).

5. Measurement of exhaust fluidity. The exhaust components resulting from the combustion of motor fuels, with the exception of nitric oxide, are theoretically clear and colorless.

The release of painted and obsolete exhaust gas indicates that the combustion process is unsatisfactory.

The presence of carbon in the exhaust gases in the form of small particles of carbon black with a size of several tens of micrometers, as well as the smallest droplets of fuel, is evidence of incomplete and poor-quality combustion of fuel and causes coloring of the exhaust gases. Unburned hydrocarbon molecules give them a blue tint, and soot - a black color. Carbon black adsorbs a large amount of aromatic hydrocarbons and therefore is a dangerous toxic component.

The ability of soot molecules to absorb and scatter light depends not only on their number, but also on their size. Therefore, there is no unambiguous relationship between the amount of soot and their smoke and color. As a result, the quality of the combustion process can be determined based on a visual assessment of the smoke and color of the exhaust gases only approximately.

All known and used methods for estimating the fluidness of exhaust gases are based on the principle of optically measuring their transparency or on measuring the content of carbon black particles deposited in them on the surface of the filter paper through which the exhaust gases pass. In the latter method, which is used in Bosch smoke meters, the degree of fluidity of the exhaust gases is determined by measuring the blackening of the paper surface. The most common smoke meter based on the principle of measuring the difference between the absorption of light by the cloud of exhaust gases and air is the Hartridge smoke meter. This device has a scale divided by 100 units per unit the degree of attenuation of light flux intensity by 1% is taken. Correctness of device readings is periodically checked by means of reference filter corresponding to smoke content of 50 units. Opacimers of this type are characterized by high stability and objectivity of readings.

Conclusion

In this project, the motor transport enterprise Avtopark LLP was considered and the re-equipment of the TO-1 Zone with an increase in production capacity was proposed, as well as calculations were made to change the design of the equipment of the NIIAT390 solidifier with subsequent introduction into production.