Ecology/4. Industrial ecology and occupational medicine
Ermolaeva N.V., Doctor of Technical Sciences Golubkov Yu.V., Ph.D. Aung Khaing Pyu
Moscow State Technological University "Stankin"
Minimizing the impact of oil cutting fluids on human health
The threat to human health and well-being associated with environmental pollution is currently one of the most urgent problems. According to the World Health Organization, environmental pollution causes about 25% of all diseases worldwide, while children account for more than 60% of the diseases caused by this cause.
Lubricating-cooling technological means (LUTS), the vast majority of which are lubricating-cooling fluids (CLL), are an integral element of the technological processes of modern metalworking industries. There are a number of requirements for oil-based coolants. In particular, they should not cause a pronounced biological effect on the skin and respiratory organs of an employee, have a minimal irritant effect when exposed to mucous membranes, have a low ability to form oil mist, and not contain 3,4-benzpyrene and some other hazardous substances.
The main risk factor for the health of those working with oil coolants is the intake of oil aerosol, formaldehyde, acrolein and other products of thermal oxidative degradation into the respiratory tract. It has been established that even with the observance of the MPC in the working area for acrolein, benzene, formaldehyde, 3,4-benzpyrene, acetaldehyde, an individual lifetime carcinogenic risk with a twenty-year production experience can reach 9* 10 -3 , and with thirty years of experience - 1.3 * 10 -2 , which is much higher than the acceptable (1* 10 -3 ) for professional groups . Despite the fact that for almost all components that make up the coolant and the products of their thermal-oxidative degradation, there are MPCs, coolant, being complex mixtures, can have an adverse effect on human health. Since it is difficult to reliably predict this effect on the basis of a theoretical analysis, an obligatory step in determining the degree of danger of cutting fluids is their toxicological assessment, which determinesLD 50 , LC 50 , the ability to irritate the skin and mucous membranes, sensitizing and mutagenic properties, hazard class.
Most often, oil coolants are made on the basis of industrialoils. Therefore, nIt is of considerable interest to determine the molecular composition of industrial oils in order to find individual compounds that are potential environmental pollutants. Such data are necessary for the development and adoption of measures to implement active methods for protecting personnel and the environment from harmful components of oil coolants.
In this work, we have studied the molecular composition of some brands of oil coolants (MR-3, MR-3K, SP-4) and industrial oil (I-40A) using a chromato-mass-spectrometric method. As a result of the research, it was found that the most harmful substances for humans and the environment in the MP-3 coolant are benzene homologues - ethylbenzene and m-xylene, present in amounts from 2.4 to 3.3 ng/g. It was also found that MR-3K coolant contains polycyclic aromatic hydrocarbons: 3-methylphenanthrene, 9- and 2-methylanthracene in an amount of 6.0 to 21.2 ng/g. 4 are halogenated organic compounds contained in an amount of 0.3 to 1.0 µg/g.
Almost all organic substances pose a danger to the environment. The most powerful carcinogens in petroleum oils are aromatic hydrocarbons (MPC 0.01..100 mg/m³), olefins (1...10 mg/m³), as well as sulfur, nitrogen and oxygen compounds. At present, it is difficult to isolate the most harmful substances for the environment, since many of them, including alkylphenols, have a structure similar to sex hormones and affect the reproductive health of people, causing an increase in cancer. For example, the carcinogenic effect of nonylphenol, which accelerates the development of cancer cells, was accidentally discovered.
One of the principles of the scientific and educational complex "Engineering ecology, labor and life safety" of MSTU "Stankin" is the priority of minimizing the impact on the environment and humans over managing this impact. The implementation of this principle lies in the fact that it is necessary to reduce the impact on the environment and humans directly at the source, and then not take measures to manage this impact through the construction of various types of treatment facilities, waste disposal, neutralization, etc.
We list the possible methods for cleaning industrial oil I-40A and the mentioned oil coolants from harmful components. Hydrotreating- the most effective method for removing all types of sulfur compounds from petroleum products. Adsorption on natural clays and other adsorbents - universal cleaning method. This work, in our opinion, should be carried out at the coolant manufacturer.
Literature:
1. Onishchenko G.G., Zaitseva N.V., Ulanova T.S. Control of the content of chemical compounds and elements in biological media: Guide. - Perm: Book format, 2011. - 520 p.
2. Lubricating-cooling technological means and their application in cutting: a Handbook / Under the general. ed. L.V. Khudobin.- M.: Mashinostroenie, 2006. - 544 p.
3. Maystrenko V.N., Klyuev N.A. Ecological and analytical monitoring of persistent organic pollutants. – M.: BINOM. Knowledge Laboratory, 2004. - 323 p.
The operation of turbine oils over time leads to its aging. This is an inevitable process, because these oils have to work in rather difficult conditions, since the oil systems of turbogenerators are under the constant influence of a number of unfavorable factors.
Factors Affecting Turbine Oil
Influence of high temperatures
When oil is heated in the presence of air, enhanced oxidation of the oil product occurs. In parallel, other characteristics of oils also change. Evaporation of low-boiling fractions leads to an increase in viscosity, a decrease in flash point, a deterioration in demulsibility, etc. The greatest heating of turbine oils is observed in turbine bearings (from 35-40 to 50-55 ºС). Oil heating occurs due to friction in the oil layer of the bearing and partly due to heat transfer along the shaft from hotter parts.
To get an idea of the current temperature of the bearing, the temperature of the oil in the drain line is measured. But even a relatively low temperature does not exclude local overheating of the oil due to the imperfection of the bearing design, its poor-quality manufacture or improper assembly. Local overheating leads to accelerated aging of turbine oils, which is a consequence of a sharp increase in oxidizability due to an increase in temperature above 75-80 ºС.
Oil can also become hot in bearing housings and control systems.
oil splatter
Oil splashing is caused by the presence in the composition of steam turbines of such components as gears, couplings, ledges, ridges on the shaft, shaft sharpening, speed controller, etc. In this case, oil is sprayed into the craters of bearings and columns of centrifugal speed controllers. Such an oil product has a large area of contact with air, which is almost always present in the crankcase. As a result, the oil is mixed with oxygen and the subsequent oxidation of the oil product. This process is intensified by the high speed of turbine oil particles relative to air.
The air in the bearing housings appears due to a slightly reduced local pressure due to suction into the gap along the shaft.
The greatest intensity of oil splashing is observed in movable couplings with forced lubrication. Therefore, in order to reduce the oxidation of oils, the couplings are surrounded by metal casings that limit the splashing of oil.
Influence of the air contained in the oil
Air can be in the turbine oil in the form of bubbles of various sizes, as well as in a dissolved state. It gets there due to capture in places of the most intensive mixing of oil with air, as well as in oil drain pipes, where the entire pipe section is not filled with oil.
As the air-containing oil passes through the main oil pump, the air bubbles are rapidly compressed. In large formations, the temperature rises sharply. Since the compression is very fast, the air does not have time to give off heat to the environment - the process is, in fact, adiabatic. Very little heat is released and the process of release itself lasts quickly. However, even this is sufficient to significantly accelerate the process of turbine oil oxidation. After passing through the pump, the compressed bubbles gradually dissolve, as well as the impurities contained in the air - dust, ash, water vapor, etc. - pass into the oil. As a result, the oil product is polluted and watered.
Oil aging due to the air it contains is most noticeable in large turbines, due to the high oil pressure after the main oil pump.
Influence of water and condensation steam
In turbines of old designs, the main source of oil flooding is steam, which escapes from the labyrinth seals and is sucked into the bearing housing. Also, watering may occur due to a malfunction of the steam shut-off valves of the auxiliary turbo oil pump. Also, water can enter the oil from the air as a result of condensation and through oil coolers.
The most dangerous is the watering of the oil after contact with hot steam. At the same time, the oil product not only absorbs moisture, but also heats up, which leads to an acceleration of its aging process.
The presence of water contributes to the formation of sludge. If it enters the bearing lubrication line, it can clog the holes in the metering washers installed on the injection lines. This is fraught with overheating or even melting of the bearing. The penetration of sludge into the control system disrupts the normal operation of spools, axle boxes and other elements of the turbine.
Also, as a result of the contact of turbine oil with hot steam, an oil-water emulsion is formed. It can get into the lubrication and regulation system, sharply degrading the quality of their work.
Influence of metal surfaces
When circulating through the oil system, turbine oil almost always comes into contact with various metals: steel, cast iron, babbitt, bronze, which also contributes to oxidation. When metal surfaces are exposed to acids, corrosion products are formed that can enter the oil. Also, some metals may have a catalytic effect on the oxidation of petroleum products.
The factors listed above, both individually and collectively, cause the aging of turbine oils. Aging is usually understood as a change in physical and chemical properties in the direction of deterioration in performance.
Signs of aging of turbine oils during operation can be considered:
- increase in viscosity;
- increase in acid number;
- flash point reduction;
- the appearance of an acid reaction of water extract;
- the appearance of sludge and mechanical impurities;
- decrease in transparency.
But the presence of even all of the listed signs does not mean that the turbine oil is not fit for use.
For use in steam turbines, petroleum products that meet the following requirements:
- acid number does not exceed 0.5 mg KOH per 1 g of oil;
- the viscosity of the oil does not differ from the original by more than 25%;
- the flash point has decreased by no more than 10 ° C from the original;
- the reaction of the water extract is neutral;
- the oil is transparent and does not contain water and sludge.
If one of the parameters or characteristics of the oil does not correspond to the rated value and cannot be restored, then such a product must be replaced as soon as possible.
Turbine oil treatment plants
As we saw above, the aging of turbine oil can lead to a number of negative consequences. The failure of turbines, their downtime and repair are very expensive. And turbine oil itself is not a cheap product. Therefore, it is advisable to invest in activities aimed at slowing down the aging process and restoring the properties of oils that have already been in operation.
Installation SMM-4T
In practice, to solve such problems, companies GlobeCore . With the help of this equipment, a comprehensive purification of turbine oils from water and various impurities is carried out. Purification systems can operate in filtration and heating modes, as well as oil filtration, drying and degassing. The result of the treatment is an improvement in the performance characteristics of turbine oils to standardized values and a significant extension of their service life.
Turbine oils are lubricating oils with a wide range of applications - in addition to being used as a lubricant for bearings and gearboxes in steam turbines and hydro turbines, as a working oil for a brake system, they are also used in compressors, fans and other mechanisms. As a rule, turbine oils consist of highly refined paraffinic base oils to which various combinations of additives are added to give the oils the necessary performance characteristics.
There are 2 types of turbine oils - with additives and without additives, classified by the Japanese industrial standards system according to the K 2213 standard.
9-1 Necessary properties that turbine oils must have
Turbine oils have a fairly wide purpose, and since they must act as a lubricant for bearings, gears, compressors, and other mechanisms under various conditions, the following requirements are imposed on them:
(1) Possess a viscosity grade suitable for (suitable) operating temperature conditions
(2) Possess antioxidant properties and thermal oxidation stability
(3) Have high anti-corrosion properties
(4) Have high demulsibility and good water separating ability
(5) Have high anti-wear properties
(6) Have high anti-foam properties.
Viscosity degree
Thermal stability and antioxidant properties
Anti-corrosion qualities
Demulsibility
Generally, highly refined base oils have good demulsibility, but when a rust inhibitor is added, demulsibility decreases, so it is important to strike the right balance.
Anti-wear properties
Anti-foam properties
Air foam, being the cause of oil oxidation, also harms the lubrication process and leads to excessive loss of oil from the oil tank, so it is important and necessary that the oil has anti-foam properties. And usually, a silicone-derived foam quencher is added as such an additive, which quickly quenches the resulting foam.
Turbine lubrication
Bearing lubrication
Since turbines are operated for a long time, this factor increases the oxidation of the oil.
Lubrication of the gear mechanism
On ships, turbines equipped with gearboxes with gears are mainly used; the same turbine oil with additives is used to lubricate the main (leading) bearings of the turbine, gearbox, bearings, outer rings of bearings and gear wheels.
Due to the fact that as the power of marine turbines increased and with a decrease in their size, the load on the gear train increased and became quite high, it became necessary to add an additional “extreme load” additive to turbine oils and oils with such additives are referred to as “extreme load turbine oil”. loads" (EXTREME PRESSURE)
Turbine speed controller
Deterioration of turbine oil parameters (oil decomposition) and its replacement rates
Therefore, the process of oil decomposition proceeds gradually, step by step. This process is expressed in a color change from red to red-brown and then to black, and the appearance of an irritating odor. At this stage, the acid number increases, sludge is formed, and anti-foam, anti-corrosion, and demulsifying properties decrease.
Since, to some extent, it is possible to control the process of oil decomposition, paying attention to those. condition of the lubrication system in the normal operating mode of the turbine, below are a few points that you need to pay attention to when periodically checking the condition of the lubrication system.
oil cooler
The presence of foreign (foreign) substances in the lubrication system.
Before filling with oil, foreign matter must be removed by flushing or blowing, and it is also important to take measures to prevent foreign matter from entering from the outside through the air ventilation system.
Of course, it is impossible to completely avoid the entry of foreign matter into the lubrication system, so it is important to regularly remove test samples from the lubrication system, or regularly inspect filters and washing equipment, and it is also important to clean the system.
Ventilation
Technical factors
For example, if air enters the internal pumping part of the system, then the oil begins to foam, if the seals are not tight enough, it connects with water and steam, if the oil pipeline comes into contact with areas with high temperatures, the oil temperature will rise if the ends of the pipes through which it returns If the oil is above the oil level, then air is mixed in, and any of these factors will accelerate the deterioration of the performance of turbine oils, so the location of the pipeline and the design of the turbine must be given sufficient attention.
Terms of replacement of turbine oils
Turbine oils are widely used for lubrication and cooling of bearings in various turbine generators - steam and gas turbines, hydraulic turbines, turbopumps. They are also used as a working fluid in turbine control systems and industrial equipment.
What properties does it have?
The turbine is a complex mechanism that must be handled with care. Turbine oils used must meet a number of characteristics:
- have antioxidant properties;
- protect parts from deposits;
- have demulsifying properties;
- be resistant to corrosion;
- have low foaming ability;
- be neutral to parts made of metals and non-metals.
All these characteristics of turbine oils are achieved during production.
Production features
Turbine oils are produced from highly refined petroleum distillates to which additives are added. Thanks to antioxidant, anti-corrosion, anti-wear additives, their performance characteristics are improved. Because of all these additives, it is important to choose oils in accordance with the operating instructions for a particular unit and the manufacturer's recommendations. If the turbine oil is of poor quality, the unit may simply fail. To achieve high quality in the production of compositions, high-quality oils are used, deep cleaning is used during processing and the introduction of additive compositions. All this in combination can improve the antioxidant and anti-corrosion properties of oils.
Primary requirements
The rules for the technical operation of various pumping stations and networks indicate that turbine oil should not contain water, visible sludge and mechanical impurities. According to the instructions, it is also required to control the anti-rust properties of the oil - for this, special corrosion indicators are used, located in the oil tank of steam turbines. If, nevertheless, corrosion appears in the oil, it is necessary to introduce a special additive against the appearance of rust into it. We offer an overview of popular brands of turbine oils.
TP-46
This oil is used to lubricate bearings and other mechanisms of various units. Turbine oil 46 shows good antioxidant properties. To create it, sulfuric paraffinic oil of deep selective purification is used. The composition can be used on ship steam power plants and in any auxiliary mechanisms. TP-46 serves as a reliable protection of surfaces of parts from corrosion, is highly stable against oxidation and does not emit precipitation during long-term operation of turbines.
TP-30
Turbine oil 30 is produced on the basis of mineral base oils, where additives are added to improve the performance properties of the composition. Experts advise using TP-30 in turbines of any type, including gas and steam ones. Moreover, the operation of the oil is available even in harsh climatic conditions. Among the distinguishing features of TP-30, one can note an excellent antioxidant capacity, a good level of minimal cavitation, and excellent thermal stability.
T-46
Turbine oils T-46 are made from low-sulphur wax-free high-quality oils without additives, which ensures the availability of its cost while maintaining all performance characteristics. The quality raw materials used for production allow reaching a certain level of viscosity for the oil, which makes it easier and more convenient to clean. The use of this composition is advisable in ship turbines, steam turbine units.
TP-22S
Turbine oil TP-22S allows lubrication and cooling of bearings, auxiliary mechanisms of steam turbines that operate at high speeds, and it can also be used as a sealing medium in sealing and control systems. Benefits of this oil include:
- excellent performance properties due to a deeply refined mineral base and an effective composition of additives;
- excellent demulsifying properties;
- excellent stability against oxidation;
- high level of viscosity;
- minimal cavitation.
This oil is used in turbines for various purposes - from steam and gas to gas turbines of power plants.
TP-22B
Turbine oil TP-22B is produced from paraffinic oils, and cleaning is carried out with selective solvents. Thanks to the additives, a good level of resistance to corrosion and oxidation is achieved. If we compare TP-22B with TP-22S, then the former forms less sediment during the operation of the equipment, it is more durable in use. Its peculiarity is the absence of analogues among domestic grades of turbine oils.
"LukOil Tornado T"
This series offers a wide range of high quality turbine oils. They are based on those produced by a special synthetic technology with the use of additives of the ashless type of high efficiency. Oils are developed in accordance with the latest requirements for compositions of this kind. It is expedient to apply them in steam and with reducers and without them. Excellent antioxidant, anti-corrosion and anti-wear properties help minimize deposit formation. The oil is specially adapted for modern high-performance turbine units.
Composition features
Modern turbine oils are created on the basis of special paraffin oils with certain viscosity-temperature characteristics, as well as antioxidants and corrosion inhibitors. If the oil is planned to be used on turbines with gear boxes, then they must have a high bearing capacity, and for this, extreme pressure additives are added to the composition.
Extraction or hydrogenation is used to obtain base oils, while high-pressure refining and hydrotreating allow achieving such characteristics of turbine oil as oxidation stability, water separation, deaeration, which, in turn, affect pricing.
For turbines of various types
Turbine oils (GOST ISO 6743-5 and ISO/CD 8068) are used for modern gas and steam turbines. The classification of these materials, depending on the general purpose, can be represented as follows:
- For steam turbines (including those with gears under normal load conditions). These lubricants are based on refined mineral oils supplemented with antioxidants and corrosion inhibitors. The use of oils is advisable for industrial and marine drives.
- For steam turbines with high bearing capacity. These turbine oils additionally have extreme pressure characteristics, which provide lubrication of gears during operation of the equipment.
- For gas turbines: these oils are made from refined mineral formulations to which antioxidants are added,
Cleaning Features
The internal parts of any mechanism eventually become unusable due to natural wear and tear. Accordingly, mechanical impurities in the form of water, dust, chips also accumulate in the lubricating oil itself as it is used, an abrasive will begin to form. It is possible to make the operation of the equipment full-fledged and longer by constant monitoring and cleaning of turbine oil to eliminate mechanical impurities from it.
It should be noted that modern oils make it possible to optimize and increase the efficiency of the production process due to the full protection of parts and components of equipment. High-quality purification of turbine oil is a guarantee of reliable operation of turbine units for a long period without failures and malfunctions of the equipment itself. If low-quality oil is used, the functional reliability of the equipment will be in question, which means that it will wear out prematurely.
The oil recovered after cleaning can be reused. That is why it is advisable to use continuous cleaning methods, since in this case it is possible to increase the life of the oil without needing to refill it. Turbine oils can be purified by various methods: physical, physico-chemical and chemical. Let's describe all the methods in more detail.
Physical
These methods purify turbine oil without violating its chemical properties. Some of the most popular cleaning methods include:
- Sedimentation: oil is cleaned from sludge, water, mechanical impurities through special settling tanks. An oil tank can be used as a sump. The disadvantage of the method is low productivity, which is explained by the long stage of delamination.
- Separation: oil is cleaned from water and impurities in a special centrifugal force separator drum.
- Filtration: With this method, the oil is purified from impurities that cannot be dissolved in it. To do this, the oil is passed through a porous filter surface through cardboard, felt or burlap.
- Hydrodynamic cleaning: this method allows you to clean not only the oil, but also the entire equipment. During operation, the oil film between metal and oil remains intact, corrosion does not appear on metal surfaces.
Physico-chemical
When using these cleaning methods, the chemical composition of the oil changes, but only slightly. These methods involve:
- Adsorption cleaning, when the substances contained in the oil are absorbed by solid highly porous materials - adsorbents. In this capacity, aluminum oxide, enamels with a whitening effect, silica gel are used.
- Flushing with condensate: this method is used if the oil contains low molecular weight acids that are soluble in water. After flushing, the performance properties of the oil are improved.
Chemical Methods
Cleaning by chemical methods involves the use of acids, alkalis. Alkaline cleaning is used if the oil is very worn out, and other cleaning methods do not work. Alkali affects the neutralization of organic acids, sulfuric acid residues, the removal of esters and other compounds. Cleaning is carried out in a special separator under the influence of hot condensate.
The most effective way to clean turbine oils is to use combined units. They involve cleaning according to a specially designed scheme. In industrial environments, universal installations can be used, thanks to which cleaning can be carried out in a separate method. Whatever cleaning method is used, it is important that the final quality of the oil is at its best. And this will increase the period of stable operation of the equipment itself.
Exposure to harmful substances (transformer oil);
| Initial data for the section "Social responsibility": | ||
| 1. Characteristics of the object of study (substance, material, device, algorithm, technique, working area) and areas of its application | The object of the study are rocks of different types. Basic research equipment; Charger, impulse voltage generator (GIN), high pressure chamber (7 MPa). Research methodology; the rocks will be supplied with a pulsed voltage of 250-300 kV. Maximum pressure applied on rocks 7MPa The working area is the laboratory No. 11 of the TPU Institute of High-Technical Physics. Research and experimental work is being carried out in the high-voltage hall. | |
| List of issues to be researched, designed and developed: | ||
| 1. Industrial safety 1.1. Analysis of the identified harmful factors during the development and operation of the designed solution in the following sequence: - physical and chemical nature of harmfulness, its connection with the topic under development; - the effect of the factor on the human body; - reduction of permissible norms with the required dimension (with reference to the relevant regulatory and technical document); - proposed means of protection; - (first collective protection, then - individual protective equipment). 1.2. Analysis of identified hazards during the development and operation of the designed solution in the following sequence: - mechanical hazards (sources, means of protection; - thermal hazards (sources, means of protection); - electrical safety (including static electricity, lightning protection - sources, means of protection - fire and explosion safety (causes, preventive measures, primary fire extinguishing agents). | Harmful factors: the content of volatile organic impurities (transformer oil), electromagnetic radiation in a wide range, noise, unfavorable microclimate conditions of the working area. Hazardous factors: electric current, fire, high pressure work. | |
| 2. Environmental safety: - protection of the residential area - analysis of the object's impact on the atmosphere (emissions); - analysis of the object's impact on the hydrosphere (discharges); - analysis of the impact of the object on the lithosphere (waste); - develop solutions to ensure environmental safety with reference to the NTD on environmental protection. | There is no negative impact on the environment. All materials used in assembly work are environmentally friendly | |
| 3. Safety in emergency situations: - a list of possible emergencies during the development and operation of the projected solution; - selection of the most typical emergency; - development of preventive measures to prevent emergencies; - development of actions as a result of emergencies and measures to eliminate its consequences. | Possible emergencies during the implementation of the project are: short circuit of residual charges, ignition of the working fluid. Preventive measures to prevent emergencies: the use of insulation, the inaccessibility of current-carrying parts, the isolation of electrical parts from the ground. Actions as a result of an emergency situation and the elimination of its consequences should be described in each labor protection instruction. | |
| 4. Legal and organizational issues of safety: - special (characteristic for the operation of the object of study, the designed working area) legal norms of labor legislation; - organizational measures in the layout of the working area. | Distances between working areas, lighting and microclimate parameters comply with the standards. Efficient and safe work is possible only if the working conditions at the workplace meet all the requirements of international standards in the field of labor protection. | |
The task was given by the consultant:
The task was accepted by the student:
Introduction
This section will consider the safety and environmental friendliness of the study of the processes of destruction of rocks by pulsed stress at a pressure of up to 7 MPa.
At the moment, there is an increase in the volume of work in the mining and oil and gas industries. There is a need to find a completely new method of drilling, which should be more economical and efficient than traditional methods of drilling. Many criteria for an effective method of destroying rocks and ores are met by an electric pulse method, which uses the energy of a pulsed electric discharge to destroy solid dielectric and semiconducting materials during their direct electrical breakdown. As the drill bit is deepened, the pressure at its end will increase. In this regard, work is underway to study the destruction of rocks, on impulse voltage at elevated pressures.
The object of research is rocks of different types (sandstone, granite, limestone). Impulse stress will be applied to the rocks, the maximum pressure is 7 MPa. Voltage amplitude 250 - 300 kV. The block diagram of the equipment required for the study is indicated in Figure 1.
Figure 1. Block diagram of the research equipment.
In order for the discharge channel to penetrate into a solid body, the surface of the solid body (sample) must be filled with a liquid dielectric. Transformer oil was taken as such a dielectric.
The working area is the High-Voltage Hall, Laboratories No. 11, IFVT.
The test chamber is shown in Figure 2. The chamber will be pressurized to 7 MPa and filled with transformer oil.
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Figure 2. Test chamber
1 high voltage input; 2 Housing; 3 Sample platform; 4 Screen mesh and polycarbonate protection;
Technogenic safety
1.1 Analysis of the identified harmful factors during the development and operation of the designed solution in the following sequence:
Exposure to harmful substances (transformer oil);
Electromagnetic field;
Increased noise level;
Unfavorable conditions of the microclimate of the working area;
Exposure to harmful substances (transformer oil);
Transformer oil is a purified fraction of oil obtained during distillation, boiling at a temperature of 300 ° C to 400 ° C. Depending on the origin of the oil, they have different properties and these distinctive properties of the feedstock are reflected in the properties of the oil. It has a complex hydrocarbon composition with an average molecular weight of 220-340 a.u., and contains the main components shown in Table 1.
Table 1. Main components of transformer oil
Of the main characteristics of the oil, we note that it is combustible, biodegradable, practically non-toxic, and does not violate the ozone layer. The density of the oil is usually in the range (0.84-0.89)×10 3 kg/m 3 .
The harmful effect of transformer oil is manifested in the fact that when replacing research samples that are impregnated with transformer oil (all this happens manually), they can soak into the tissue, human blood vessels.
To protect a person from harmful factors, personal protective equipment is used; gloves (PER107).
Table 2. Characteristics of PER107 gloves
Oil and petrol resistant gloves have excellent resistance to oil and oil products. Recommended for use when carrying greasy and oily items, servicing equipment. Provides good grip on oily surfaces. They are made of high quality two-layer PVC on a knitted basis.
Electromagnetic field
The consequences of exposure to electromagnetic radiation on the human body are functional disorders of the nervous system, manifested in the form of vegetative dysfunctions of neurasthenic and asthenic syndrome. Persons who have been in the zone of electromagnetic radiation for a long time have complaints of weakness, irritability, fatigue, memory loss, and sleep disorders.
Hygienic standards for staying in an electric field, established on the basis of direct (biological) effects on humans, are given in table 3
Table 3. Hygienic standards for staying in an electric field SanPiN 2971-84
Creating safe conditions for conducting research under the influence of existing electromagnetic fields is reduced to ensuring acceptable levels of electric field strength and induced voltage at workplaces; limiting the time spent in a zone of increased tension; observance of standardized distances to elements that may be under dangerous potential; protective earthing device; use of means of collective and individual protection.
Since the source of electromagnetic fields is in a metal case (Figure 2; 2), it is also insulated with a metal mesh and a polycarbonate layer (Figure 2; 4), which is a protective screen from the electromagnetic field. In this regard, the magnitude of electromagnetic radiation is insignificant E ≤ 5 kV/m, there is no need to use additional means of collective and individual protection.
Increased noise level
The harmful effects of noise are not limited to the effect only on the hearing organs. An increased noise stimulus negatively affects the human nervous system, the cardiovascular system, and causes severe irritation. Excessive noise can cause insomnia, fatigue, aggressiveness, affect reproductive function and contribute to serious mental disorders.
The main source of noise is the GIN and the research chamber. The nature of the noise is tonal; there are clearly expressed discrete tones in the noise spectrum. The noise level exceeds the maximum permissible noise level at the workplace, L add ≤ 150 dBA. Champion headphones (C1002) are used as personal protection, which is on the balance sheet of laboratories No. 11, IFVT
Compliance with the noise limit does not exclude health problems in hypersensitive individuals.