Method to detect parameters of local fire

FIELD: measurement equipment.

SUBSTANCE: invention relates to the field of investigation of materials of building structures of a building using thermal means. The method to detect parameters of a local fire includes technical visual inspection of building structures in a wood floor of a building, which were exposed to thermal gradient under conditions of the local fire; detection of a scheme of fire impact at components of the floor; determination of type and grade of building wood, indices of its moisture and density in natural condition, solidity of elements of the wooden floor, finding the normative resistance of building wood for bending and speed of its burning, differing by the fact that technical visual inspection of the building wooden floor is complemented with instrumental measurements of geometric dimensions of the burning area, a control cell of the floor in the fire site is assigned, the area of cross section of the floor cell openings is measured, the index of floor cell opening is calculated; the thickness of the charring layer is determined in the cross section of wood floor elements; the combustible material volume value is calculated, as well as mass speed of burning of building pine wood in the floor cell and coefficient of reduction of pine wood burning speed, then they detect duration of local fire and maximum temperature of local fire, which are calculated on the basis of specified ratios.

EFFECT: invention provides for valid assessment of main parameters of past fire damage, as well as reduced labour intensity and timing for technical visual inspection of thermally damaged elements of a building wooden floor.

2 cl, 4 dwg, 1 ex

 

The invention relates to the field of materials research building structures using thermal means, and is intended, in particular, to estimate the parameters of the local fire (duration-temperature: τloc, min - tloc,,max, °C) by studying the effects of fire effects field of fire on wooden floor with air cavities inside them.

The known method of identification of parameters of the local fire, including the manufacture of fire "camera - Libra", the initial setting of her recording equipment before the start of fire tests, filling the chamber with a combustible loading in the form of bars of wood, burning, construction experienced the changes in the cell average temperature in time (ton°C - τon, min) and overlay graphics on it standard fire (tSt°C - τSt,,min), comparing the square plots of temperature; the area of the plot of temperature experienced fire limit of the ordinate tmin=600°C as the temperature of the end of the fire (τOK, min) / Resistance of buildings / V. P. Bushev, V. A. Pchelintsev, V. S. Fedorenko, A. I. Yakovlev (chap 2, item 4: Basic methods for studying the temperature of fire regimes; Fig. 5), Stroyizdat, Moscow, 1970, p. 17-21 / [1].

For reasons that impede the achievement of specified following technical re�the result when using the known method, include the following: each fire occurred in the building of the individual, the same manufacturer of the firing chamber (the fragment of the building), which is similar to the building, damaged by fire, requires high material costs and extended time tests, but the results of the experimental study of thermal conditions substantially different from those of full-scale fires; a fire "camera-Libra" perhaps a study of fire development, mainly for residential rooms, for a variety of rooms for other purposes (industrial buildings, warehouses and other) a method of estimating the parameters of the fire is not used, the estimation of intensity of natural fire zones fire effects do not produce; the schedule of change of temperature with time in the conventional method is limited by the ordinate of tmin=600°C (the temperature of end of fire), that for most cases of full-scale fires false.

The known method of detection of local parameters of fire in the premises of various buildings, including the definition of the integral thermal parameters freely growing fire in the room, revealing the appearance of spontaneous combustion (burning, controlled fire load and ventilation); the calculation of the volumetric average temperature in the room; the view of the mathematical description of change of temperature in freely developing PL�e depending on the design fire load, refer to wood, and duration of the initial stage / GOST R 12.3.047 - 98 ssls. Fire safety of technological processes. General requirements. Control methods (Appendix To: "Methods of calculating the temperature in the premises of various buildings"). M.: Gosstandart of Russia, 1998, pp. 33-38 [2].

For reasons that impede the achievement of specified following technical result when using the known method include the following: it is impossible to define changes of parameters of the fire by zones of intensity fire effects on structures of the building; inaccurate estimation of thermal parameters is not free of a developing fire (for example, with regard to impaired gas exchange).

The closest way to the same destination to the claimed invention on the totality of symptoms is the method of detection of local parameters of fire in the building by studying the effects of fire effects on structures, including the technical inspection of wooden structures exposed to fire effects field of fire; an approximate description of the fire development and condition of construction after delineating the zone of the destructiveness of fire effects on parts of the building; approximate determination of the parameters of thermal regime of fire / Ile�n, N. And. Technical examination of buildings damaged by fire (CH. 2 "Study of fire effects of fire on structures of buildings"), Moscow: stroiizdat, 1983, pp. 82-110 [3] is taken as a prototype.

For reasons that impede the achievement of specified following technical result when using the known method include the following: identification of the main parameters of the incident, the local fire according to the degree of destructiveness (intensity) of fire effects on the surveyed sites of wooden structures can be made approximately, with great accuracy.

The invention consists in the following: the problem to which the invention is directed, is to increase the accuracy and reliability of detection of local parameters of fire (temperature-time) by examining the effects of fire exposure on the wooden structure of the building, reducing the complexity and reducing the time of inspection and materials testing of thermally damaged structures.

The technical result - obtaining reliable estimates of the main parameters of the past local fire according to the degree of destructiveness (intensity) of fire effects on the surveyed sites of wooden structures; determination of the duration field of the local fire; nah�actual conviction of the combustible load, acting with the fire at the surveyed sites of wooden structures of the building; finding the highest, possible, local temperatures of the fire; determination of the thickness of the charred layer of wood with regard to the shape of the cross section of wooden structures and circuits of heating; mathematical description of change of local temperature fire, depending on the mass rate of burning of construction wood in conditions of impaired gas exchange; decrypting data recorded by timber building structures serving the natural temperature indicator; reducing the complexity and reducing the time of inspection, material testing hermopolitan wooden structures and material costs for restoration works in the building; simplify post-processing of results of research of parameters of the local fire.

Said technical result of the invention is achieved in that in the known method of identification of parameters of the local fire, including the technical inspection of building construction the wooden floors of the building subjected to a thermal gradient in the local conditions of the fire; the identification scheme of fire effects on the constituent elements of the overlap; the mouth�the identification of species and varieties of construction wood, indicators of its density and moisture content in the natural state, the massiveness of the elements of wooden floors, a finding of regulatory resistance of building wood bending and speed of burnout, the feature is that a technical inspection of the wooden ceilings of the building complement the instrumental measurements of the geometric dimensions of the area of burning, prescribed control cell overlap in the fire, measure the cross sectional area of the openings of the cell overlap, compute the index of premnote cell overlap; determine the thickness of charring cross section of the elements of wooden floors; calculate the value of the combustible load, the mass flow rate of burnout pine wood construction in a cell overlap and the ratio of speed reduction burn pine wood, then identify the duration of the local fire and local maximum temperature of a fire, a rate premnote cell overlap is calculated by the algebraic equation:

where α is the index of premnote cell overlap; And.- the area of the opening, cracks in the walls of the cell, m2;mountains- the burning area in the cell overlap, m2; mass rate of burning pine wood mν;sho, kg/(m2·min), the cell shut off�making in conditions of poor gas exchange at the local fire determined by the algebraic equation:

where mν,sho- the mass flow rate of combustion of wood kg/(m2·min) in case of problems with gas exchange; νabout- linear charring rate of wood (mm/min) during normal gas exchange calculated by the mathematical expression:

where ψo,i=1÷1,33 - measure, taking into account the location of the wooden elements overlap in space, ρ is the density of wood, kg/m3;

- A comprehensive index of terms burnout of wood under normal gaseous exchange calculated by the mathematical expression:

where Ruregulatory resistance (MPa) wood bending; ω - moisture content, %; b - Board thickness (cm) wooden reel ceilings;

δou- the thickness of the layer of charring (cm) wooden Board Nakata calculated by the algebraic equation:

Jσothe power intensity of stresses in the wooden Board roll forward to the start of a fire within (0,1÷0,9);

the ratio of speed reduction of the burning of pine wood (kro) at different rate of premnote (α) cells of overlap calculated by the algebraic equation:

where kth- the ratio of speed reduction burn wood�s in the cell overlap in conditions of poor gas exchange at the local fire; mν,α- the mass flow rate of combustion of wood (kg/(m2·min)) under different gas exchange; mν,max=0,88 kg/(m2·min) is the maximum mass rate of burning pine wood in normal gas exchange;

the duration of the local fire τlocmin, calculated by the algebraic equation:

where τloc- the duration of the local fire, min; g0- the combustible loading in the cell overlap, kg/m2; mν,sho- the mass flow rate of combustion of wood in conditions of poor gas exchange, kg/(m2·min);

the maximum temperature local fire tτ,zgo,°C, in conditions of impaired gas exchange local fire calculated by the formula:

where tτ,sho- maximum temperature of hot gases (°C) in the case of problems with gas exchange; mν,sho- the mass flow rate of combustion of wood (kg/(m2·min)) in the case of problems with gas exchange.

Identification of parameters of the past local fire conducted at positive and negative temperatures.

In the drawings:

Fig. 1 shows a plan of the cell to the wooden floors with load-bearing steel beams in axes 5-7 / f-G building: 1 - steel girders No. 32 (h=320 mm); 2 - wooden beams (b×h=200×50 mm).

Fig. 2 �zobrazeno section 1-1 of the cell floors: 1 - steel girders No. 32 (h=320 mm); 2 - wooden beams (b×h=200×50 mm); 3 - vertical bar (b×h=200×50 mm); 4 - upper decking (timber Board - 30 mm); 5 - subfloor (cutting Board - 50 mm); 6 - timber in the body of an I-beam (70×320×1130 mm); 7 - lower deck (ceiling; cutting Board - 50 mm); 8 - plaster sheathing (δ=30 mm).

Fig. 3 shows a cross-section 2-2 of the cell wooden floors: (positions 1-8 will see. 2).

Fig. 4 shows a graph of the internal temperature of a fire in the ceiling depending on the mass rate of burning of construction wood: I - the data of experience; II - the graph of the function (8).

A causal relationship between the set of features and the technical result lies in the following.

The development of methods for assessment of thermal (fire, fire) download, effect on wood, provides more accurate and reliable estimate of the main parameters of the temperature regime of the local fire and, as a consequence, the degree of destructiveness of a local fire on the study design of the building.

The control cell of a wooden structure prescribed by the results of technical inspection, which involves the detection and fixation of the lesion and the adjacent areas of the structural damage, the finding of termovalle characterizing local temperature regimes of the fire.

�distribution in the process of inspection of the thickness of the charred layer of wood δ oumm, allows to reliably estimate the magnitude of the complex index of burning wood.

Decrypting data recorded by the wood building construction, serving the natural thermal indicator, is to measure the thickness of the charred layer of wood, in defining the conditions of heating of the cross section of the structural member.

Reducing the complexity and reducing the time of inspection, material testing hermopolitan wooden structures and reduction in the cost of the reconstruction is possible using the proposed method of identifying parameters of local fire in a hollow wooden floor.

Simplify post-processing of the results of the study fire is possible using the proposed method of identifying the duration and maximum temperature of the local fire presents analytical dependences(7)÷(8).

An example of a practical application. Technical inspection of the parts overlapping the 2nd floor is installed, that subject to the restoration of two-storey commercial building with massive stone walls contains wooden floor with steel load bearing beams in the form of a rolled I-beams No. 32 of steel grade St.3, set with a step of 1.5 m. the Composition of overlapping second�of floors: 1 - steel girders No. 32 (h=320 mm); 2 - wooden beams (b×h=200×50 mm); 3 - vertical bar (b×h=200×50 mm); 4 - upper decking (timber Board - 30 mm); 5 - subfloor (cutting Board - 50 mm); 6 - timber in the body of an I-beam (70×320×1130 mm); 7 - lower deck (ceiling; cutting Board - 50 mm); 8 - plaster sheathing (δ=30 mm).

The ceiling structure was divided by a longitudinal metal beams and wooden cross bars in confined spaces (cells) with narrow slits through which was hampered gas exchange in conditions of slow combustion wood fire. In terms of internal local fire in hollow core slab slow combustion wood was incomplete. Lack of gas exchange caused by insufficient air in a separate closed volumes (cells) floors of the building. Specific combustible load in the confinement cell hollow core slab is equal to:

The pine wood is a combustible material; humidity ω=9%, density ρ=500 kg/m3; thermal conductivity of λ=0,37 W/(m·K); heat of combustion 20,32 MJ/kg; rate of more than 2.1 Flammability; ignition temperature 400°C; the smoulder temperature of 295°C.

The value of the mass flow rate of burnout mv, kg/(m2·min), decreases significantly with the decrease in the area of the opening (A., m2) through �which is gas exchange.

You want to identify the maximum temperature and the duration of the local fire.

Solution: 1. Specific area (the projection on a horizontal surface) combustion in a confined space of a cell of overlap calculated by the equation:

where l1- step steel I-beams No. 32, m; l2- step transverse wooden bars overlap, m.

The size of the area of the opening (slit) hollow core slab for access of air to the combustion calculated by the equation:

where h.=N-2·δ1-Nσ=520-2·50-320=100 mm=0.1 m - slit width. The rate of premnote enclosed space (cells) of overlap calculated by the algebraic equation (1):

2. The mass flow rate of burnout reference pine wood (at the rate of premnote α=0,1) is calculated by the algebraic equation:

3. Under normal conditions, gas exchange maximum mass speed burnout reference wood mv,max=0,88 kg/(m2·min), consequently, the rate of decrease in the rate of burnout of wood in case of problems with gas exchange in the fire (SGO) is calculated by the algebraic equation (6):

4. The average linear rate of charring υ0mm/min, etc�wood is calculated by mathematical expression (3):

where C is a complex parameter conditions burnout construction of wood under normal conditions, gas exchange, as defined in mathematical expression (4):

5. The mass rate of burning of wood mv, kg/(m2·min), during normal gas exchange in the fire is calculated by the algebraic equation (9):

where ν0=1,12·10-3- the linear speed of burning wood, m/min; ρ=500 - pine wood density, kg/m3.

6. The mass rate of burning pine wood mv,sho, kg/(m2·min), in the case of problems with gas exchange internal local fire confined cell of overlap calculated by the algebraic equation (10):

7. The duration of the local fire τlocmin calculated by the algebraic expression (7) is equal to:

8. The maximum temperature of the hot gases of the local fire surrounding the steel I-beams in confined spaces (cells) wooden floors in case of problems with gas exchange, we calculate by the formula (8):

These studies of full-scale fire, reduced to the camp�properly, were used to assess destructiveness local fire on wooden floor with steel beams in the process of restoration with elements of reconstruction of a monument of history and culture "Manor Curling", Samara, Frunze str., 159/15; (2009-2013 ).

Sources of information

1. The resistance of buildings / V. P. Bushev, V. A. Pchelintsev, V. S. Fedorenko, A. I. Yakovlev (chap 2, item 4: "the Main provisions of the methodology of the study of temperature regimes of fires"; Fig. 5). Stroyizdat, Moscow, 1970, p. 17-21.

2. GOST R 12.3.047 - 98 SSLS. Fire safety of technological processes. General requirements. Control methods (Appendix To: "Methods of calculating the temperature in the premises of various buildings"). M.: Gosstandart of Russia, 1998, pp. 33-38.

3. Ilyin N. And. Technical examination of buildings damaged by fire (CH. 2 "Study of fire effects of fire on structures of buildings"). M.: stroiizdat, 1983, pp. 82-110.

1. A method of detecting parameters of local fire, including the technical inspection of building construction the wooden floors of the building subjected to a thermal gradient in the local conditions of the fire; the identification scheme of fire effects on the constituent elements of the overlap; the establishment of species and varieties of construction wood, indicators of its density and moisture content in natural with�ground state, the massiveness of the elements of wooden floors, a finding of regulatory resistance of building wood bending and speed of burnout, characterized in that the technical inspection of the wooden floors of the building complement the instrumental measurements of the geometric dimensions of the area of burning, prescribed control cell overlap in the fire, measure the cross sectional area of the openings of the cell overlap, compute the index of premnote cell overlap; determine the thickness of charring cross section of the elements of wooden floors; calculate the value of the combustible load, the mass flow rate of burnout pine wood construction in a cell overlap and the ratio of speed reduction burn pine wood, then identify the duration of the local fire and local maximum temperature of a fire, a rate premnote cell overlap is calculated by the algebraic equation:

where α is the index of premnote cell overlap; And.- the area of the opening, cracks in the walls of the cell, m2;mountains- the burning area in the cell overlap, m2; mass rate of burning pine wood mv,sho, kg/(m2·min), the cell overlap in conditions of poor gas exchange at the local fire some�represent by the algebraic equation:

where mv,sho-the mass flow rate of combustion of wood kg/(m2·min) in case of problems with gas exchange; νabout- linear charring rate of wood (mm/min) during normal gas exchange calculated by the mathematical expression:

where ψo,i=1÷1,33 - measure, taking into account the location of the wooden elements overlap in space, ρ is the density of wood, kg/m3With a comprehensive index of terms burnout of wood under normal gaseous exchange calculated by the mathematical expression:

where Ruregulatory resistance (MPa) wood bending;
ω - moisture content, %; b - Board thickness (cm) wooden reel ceilings; δou- the thickness of the layer of charring (cm) wooden Board Nakata calculated by the algebraic equation:

Jσothe power intensity of stresses in the wooden Board roll forward to the start of a fire within (0,1÷0,9);
the ratio of speed reduction of the burning of pine wood (kth) at different rate of premnote (α) cells of overlap calculated by the algebraic equation:

where kth- the ratio of speed reduction burn wood in a cell overlap in conventional�the conditions of poor gas exchange at the local fire; mv,α- the mass flow rate of combustion of wood (kg/(m2·min)) under different gas exchange; mv,max=0,88 kg/(m2·min) is the maximum mass rate of burning pine wood in normal gas exchange;
the duration of the local fire τlocmin, calculated by the algebraic equation:

where τloc- the duration of the local fire, min; g0- the combustible loading in the cell overlap, kg/m2; mv,sho- the mass flow rate of combustion of wood in conditions of poor gas exchange, kg/(m2·min);
the maximum temperature local fire tτ,sho, °C, in conditions of impaired gas exchange local fire calculated by the formula:

where tτ,sho- maximum temperature of hot gases (°C) in the case of problems with gas exchange; mv,sho- the mass flow rate of combustion of wood (kg/(m2·min)) in the case of problems with gas exchange.

2. A method according to claim 1, characterized in that the identification parameters held local fire conducted at positive and negative temperatures.



 

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4 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of increasing the thermal-oxidative stability of lubricating oils, in accordance to which samples of lubricating oil are thermostatted by heating in a hermetic cup without mixing for the constant time at atmospheric pressure and fixed temperature, which at each thermostatting of the new sample is step-by-step increased in the range of temperatures, determined by the purpose of the lubricating oil, after heating sampling and testing of the thermostatted samples for resistance to oxidation are carried out. Sampled is a constant weight sample, which then is heated in the presence of air with mixing for a specified time depending on the basic base of the lubricating oil at constant temperature and constant mixing rate, the oxidised samples are photometrically scanned, the coefficient of the light flow absorption is determined, with the determination of the graphical dependence of the change of the parameter of thermo-oxidative stability evaluation on the thermostatting temperature, which is used to determine the optimal temperature of thermostatting, providing maximal resistance to oxidation, characterised by the fact that as a criterion for the evaluation of the thermo-oxidative stability of the lubricating oil taken is a resource of the thermostatted oil work capacity. In the process of testing each new thermostatted sample for resistance to oxidation the sample of the oxidised oil is sampled after equal time intervals, the coefficient of the light flow absorption is determined by photometry, graphical dependences of the light flow absorption coefficient on the oxidation time of the thermostattted oils are built at each temperature of thermostatting, and used to determine the time of reaching the light flow absorption coefficient of the selected value for each oxidised thermostatted oil at different temperatures, the graphical dependence of the time for reaching a selected value of the coefficient of absorption of the light flow of the oxidised thermostatted oils on thermostatting temperature is built with the point of the said dependence with the maximal ordinate, characterising the resource of work capacity being used to determine the temperature of thermostatting, ensuring the maximal resistance to oxidation.

EFFECT: ensuring self-descriptiveness of the increase of the thermo-oxidative stability of lubricating oils and increase of their work capacity resource.

2 cl, 1 tbl, 3 dwg

FIELD: test equipment.

SUBSTANCE: device includes gas generator and operation part with structural material sample, connected in series. Gas generator features removable mixing head. Cylindrical combustion chamber of the gas generator features ignition device and orifice plate. Operation part includes interconnected clamping flange with central hole and flange holding a sample. Central longitudinal axes of flange and sample are coincident. Internal cylindrical surface of clamping flange forms an annular slot with the sample surface, the slot joins a cavity ending with output nozzle through end outlet holes in the flange around sample.

EFFECT: possible maintenance of required pressure-heat loading modes for samples, modelling natural thermal stress state of structural materials of various aggregates operating in alternate heat modes.

1 dwg

FIELD: chemistry.

SUBSTANCE: method comprises drying a polymer solution until complete evaporation of water; heating the polymer formed after drying the polymer solution, and determining the temperature range of active decomposition of the polymer at a given heating rate, as well as the degree of decomposition of the polymer in said temperature range; drying, performing thermal analysis in the temperature range which includes the temperature range of active decomposition of the polymer, and calculating weight loss of a weighed amount of the sample of porous medium and a weighed amount of the same sample of porous medium after pumping the polymer solution; determining the weight concentration of the polymer that has penetrated the porous medium based on the obtained values.

EFFECT: high accuracy of the obtained data and rapid analysis.

6 cl, 3 dwg

FIELD: measurement equipment.

SUBSTANCE: invention refers to measurement equipment and can be used for automatic determination of metal concentration in ore. According to the method before control of grade of ore, ore passes through conveyor without metal impurities. For heating, area thermal source is used, which width does not exceed conveyor width. After time τspec when heating is finished, measured is average value of temperature based on heated surface of ore without metal T1av. Based on these measurements, formed is calibration curve. Then ore containing metal is continuously supplied to conveyor and heated. After time τspec average value of temperature Tavi is measured on each i frame. Value Tavi-T1av is determined based on calibration curve. Using value (Tavi-T1av), determined is percentage of metal in ore. Besides, a device for implementation of the above method is proposed.

EFFECT: improving reliability of determination of metal concentration in ore.

6 cl, 7 dwg, 1 tbl

FIELD: test equipment.

SUBSTANCE: test bench comprises the appliances to place the unit under test thereat, source of temperature effects with water feed and drain systems arranged under said unit and vertical screen. The latter is arranged along the edges of said source and secured at the columns and elevated above soil to vary the spacing between soil level and source lower edge. Besides it incorporates the system of protection against satellite observation of tests and unit under test. Said system comprises horizontal screen secured from above at vertical screen columns. Said vertical screen consists of metal frame and refractory metal cables spaced in parallel along the frame lengthwise axis and over width exceeding the object overall dimensions. Said cables are braided in crosswise direction at the screen centre part by nichrome bands completely covering the object outlines.

EFFECT: higher accuracy of tests, protection against observation from space.

3 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment and can be used for heating and temperature measurement of specimens, which are transparent in an infrared (IR) radiation region. The invention proposes a method for determination of temperature of specimens, which are transparent in an IR region, subject to action with flows of charged particles or electromagnetic radiation, which involves heating or cooling of specimens, measurement of temperature of specimens by means of thermocouples. Specimens are placed in a closed housing made from material with high thermal conductivity and located in a vacuum chamber; air is pumped out till the pressure is 10-3-10-5 Pa; the housing is heated or cooled at the specified temperature interval. Continuous preliminary temperature measurements are performed with thermocouples located outside and inside the housing together with the test specimens till temperature stabilisation moment. Then, final temperature measurements are performed with these thermocouples at a stabilisation moment of the temperature that coincides with the temperature of the test specimen till external action with flows of charged particles or electromagnetic radiation. External action is performed; after external action is completed, a specimen temperature measurement procedure is repeated.

EFFECT: improving accuracy of determination of temperature of specimens transparent in an IR region.

1 dwg

FIELD: measurement equipment.

SUBSTANCE: group of inventions relates to measurement equipment and can be used for testing of fire-resistant efficiency of protective compounds and coatings for timber. The proposed method involves preparation of a specimen, flame action on the specimen, temperature measurement of exhaust gaseous combustion products, measurement of weight of the specimen and determination of weight loss, as per which fire-resistant efficiency is determined. Specimen weight measurement is performed continuously during flame action on the specimen and after the action is completed, and a moment exceeding the limit weight loss established by classification or moment of stabilisation of specimen weight after completion of its burning is taken as a test completion moment. This method is implemented by a device containing a chamber for arrangement of a specimen, a gas burner, an exhaust system with a thermoelectric converter, an instrument for measurement and recording of temperature of exhaust gaseous combustion products. The device is also equipped with a unit for automatic measurement and recording in time of specimen weight during fire tests, which includes a lever mechanism made so that a specimen holder can be installed and connected to a weight measurement instrument connected to the processing and recording unit.

EFFECT: obtaining more accurate data for investigation of a fire protection mechanism.

5 cl, 1 tbl, 4 dwg

FIELD: power engineering.

SUBSTANCE: reactor vessel steel samples are heated to temperature from 300°C, their further ageing is carried out at this temperature within certain time, subsequent tests of samples are carried out for impact bending, and test results are analysed to determine the value of the shift of critical brittleness temperature, at the same time samples of reactor vessel steel in process of ageing at the temperature of reactor vessel operation of 300-320°C are additionally exposed to neutron radiation with flux of 1011-1013 n/cm2·sec for 103 hours, after that they perform baking at the temperature of 400-450°C with duration of at least 30 hours, and assessment of extent of steel embrittlement is determined using the value of shift of critical brittleness temperature ΔTk(t) as a result of thermal ageing for the time making more than 5·105 hours, in accordance with a certain mathematical expression.

EFFECT: increased accuracy of assessment of extent of embrittlement of VVER-1000 reactor vessel embrittlement as a result of thermal ageing.

3 tbl

FIELD: measurement technology; material quality control.

SUBSTANCE: method involves testing lubricant material sample in presence of air with stirring constant volume under optimum temperature selected with its dependence on lubricant base and a group of operational properties during a time interval characterizing equal oxidation degree taken into account. Acting in equal time intervals, absorption coefficient is measured for luminous flow absorbed by oxidized lubricant material by applying photometry methods. Viscosity and thermal oxidative stability coefficient Ktos are calculated by using relationship like Ktos = Ka μ0in, where Ka is the luminous flow absorption coefficient of oxidized lubricant material; μ0 and μin are the viscosities of oxidized and initial state lubricant, respectively. Graphic dependence of thermal oxidative stability coefficient against luminous flow absorption coefficient of oxidized lubricant material is plotted. Rate of oxidation end products release and their influence upon tested lubricant viscosity growth is determined from plot slope angle tangent with respect to abscissa axis after inflection point. The inflection point coordinates are used for determining the starting point the oxidation end products release begins.

EFFECT: high reliability of estimation method.

4 dwg

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