Method of assessing compatibility of fuels for jet-propulsion engines with rubber

FIELD: investigating or analyzing of materials.

SUBSTANCE: method comprises preliminary conditioning of rubber specimens in paraffin hydrocarbon with 12-16 atoms of carbon in the atmosphere of neutral gas and in the fuel to be tested at a temperature of 130-150°C for 3-5 hours.

EFFECT: enhanced reliability.

1 dwg, 2 tbl, 1 ex

 

The invention relates to methods for the assessment of the operational properties of fuels, in particular the compatibility of fuels for jet engines (jet fuel) with rubbers mainly based on the nitrile rubber used in the fuel systems of aircraft gas turbine engines, and can be used in petrochemical, aviation and other industries.

Mechanical rubber goods (MRG), including rings are used as sealing elements in the fuel systems of aircraft gas turbine engines (GTE). In the environment of aviation kerosene RTI exposed to aggressive components, as a result of which the physico-mechanical properties of rubber are reduced. Loss of elasticity of the seals, the appearance of cracks on them, leads to the loss of their health. Internal leakage of the fuel elements of the automatic control of the CCD leads to failures and malfunctions of aviation technology: freeze or promotion of revolutions of the rotor; the omission or nevklyuchenie afterburner, etc. In the presence of leaking fuel from the engine parts (leakage rubber seals) may be danger of fire on Board the aircraft. As shown by operating experience, the intensity reduction of physico-mechanical properties of esinovich parts increases with increasing temperature in the fuel system.

The jet fuel (jet fuel) can have significantly different effects on RTI depending on the brand, but also from the mode of production within the same brand.

Currently used methods of assessment of jet fuel compatibility with RTI, based on the determination of changes of tensile strength and relative elongation of the samples of rubber in the form of blades after their contact with the fuel at elevated temperatures.

So, there is a method of determining physical and mechanical properties of rubbers, including sample processing rubber in the form of blades by type (GOST 270. Determination of tensile strength of rubber at break) stream heated to 110-150°With fuel containing gas in equilibrium concentration with periodic (3-7 times) change fuel 3-6 hours after test completion for each of the blades on a tensile testing machine according to GOST 9.024 (unified protection against corrosion and ageing. The rubber. Test methods for resistance to thermal aging) determine the tensile strength and elongation (USSR AC No. 506807, G01N 33/44), compare these figures with valid and mismatch estimate the metric compatibility of the fuel with rubber.

There is also known a method of determining the performance properties of rubber on the basis of nitrile rubber in jet fuel, including serial is inuu extract samples of the rubber in the form of blades by type (GOST 270) at 130-150° With the first fuel - extractant for 3-5 h, and then tested in the fuel when it is circulating and bubbling air with a flow rate of 20-30 cm3/min. as fuel-extractant use the test fuel containing of 0.003 wt.% antioxidant additives "BHT", processing in him samples of rubber is carried out in two stages for 3 hours each with the change of fuel in each stage (SU 1111108 A, G01N 33/44).

After completion of the testing for each of the blades on a tensile testing machine according to GOST 9.024 determine tensile strength σ and elongation ε. Based on the data, compute the coefficients of the aging of the rubber Toσand Kεby the following formulas:

Kσ21, Kε21,

where σ1and σ2- the tensile strength of rubber before and after the test, respectively, N/m2;

ε1and ε2- elongation of the rubber before and after the test, respectively, %.

Find the period of ageing of rubber - number of stages of heating, after which the values of the coefficients Kσand Kεexceed the value of 0.5. When conducting a six - and devatating test build of graphics according Toσand Kεthe number of stages through which and find the period of aging of rubber in the test fuel, which is make a conclusion about the compatibility of the fuel with rubber. The maximum divergence of the parallel definitions should not exceed one stage of the test.

Closest to the claimed method according to the technical nature and is used as a prototype is a method for determining aging of the rubber in jet fuel (USSR AC No. 561137, G01N 33/44), in which the test samples of the rubber in the form of blades by type (GOST 270) is carried out in two stages: the first stage of rubber within 3-5 h extracted antioxidants. The extraction is carried out in paraffin hydrocarbon with 12-16 carbon atoms (is a good extractant antioxidants) in the atmosphere of a neutral gas (nitrogen) at a temperature of 140-150°C. In the second stage are in contact rubber samples with the test fuel at 130-150°and a volume ratio of the phases, the fuel - air equal to 1:(2.5 to 5). Upon completion of testing for each of the blades on a tensile testing machine according to GOST 9.024 determine the tensile strength and elongation. The assessment of the compatibility of rubber with jet fuel is performed by comparing the obtained values of mechanical strength of the samples after testing requirements for the appropriate brand of fuel.

Common deficiencies described methods should be considered significant, the test length and the complexity associated with the need for additional equipment (razran the th machine) and snap (stamped "B" for cutting blades of rubber).

In addition, the disadvantage of the prototype is the lack of reliability of the results, due to the inadequacy of the test conditions full-scale operating conditions, so as rings in parts of fuel systems are in the stressed (compressed) state, as in the known method prototype there is no accounting for this load. The lack of information about the change of physico-mechanical properties of the samples during the test without removing them from the reaction vessel and destruction also complicates the known method.

The technical result of the invention is to increase the reliability of determining compatibility of jet fuel with RTI with simultaneous assessment of resource RTI through the creation of test conditions close to the conditions.

This technical result is achieved by the known method of assessing the compatibility of jet fuel with rubber used in the fuel systems of gas-turbine engine comprising the sequential exposure of the samples of rubber within 3-5 h in paraffin hydrocarbon with 12-16 carbon atoms in the atmosphere of neutral gas in the test fuel at a temperature of 130-150°in sealed containers for at least 3 hours according to the invention as a sample use rubber o-ring fuel system GTE, set the maximum value of its axially the deformation when contacting the sealing ring with the test fuel at a temperature of 130-150° Periodically load it up to the specified maximum axial strain at the end of each period of loading fix the compressing force, the test finished at the time of stabilization efforts compression, fixed period of time reduce the compression force of from its maximum Pmaxto the minimum Rminvalues, calculate the speed of the compression efforts by the formula:

where

Wn- speed reduction efforts compression ratio, H/h;

Pmax- the maximum value of the compression force of the sealing ring to a specified maximum allowable axial deformation, N.;

Pmin- the minimum value of the compression force of the sealing ring to a specified maximum allowable axial deformation, N.;

Δτ - the length of time reduction efforts compression of the sealing ring from the maximum to the minimum value, h,

and when the values of 0.9≤W≤2,0 consider fuel for jet engines compatible with rubber.

The essence of the invention consists in the combination of technological operations, consisting in the sequential exposure of the samples of rubber within 3-5 h in paraffin hydrocarbon with 12-16 carbon atoms in the atmosphere of neutral gas in the test fuel at a temperature of 130-150°s distinctive is: as sample use rubber standard rubber o-ring, which during its contact with the test fuel is periodically compressed in the axial direction before deformation values corresponding to the operational, at the end of each period of loading fixed compression effort, get the dependence of the mechanical properties of the sample during the test without removing it from the reaction vessel and destruction. Thus, we create the conditions of the aging of the sample of rubber in the fuel, similar to the conditions the rubber in the fuel system of the CCD, allowing you to more objectively assess the compatibility of the fuel with rubber, used for the manufacture of seals in the form of rings.

The drawing shows a block diagram of an installation implementing the method of assessing the compatibility of fuels for jet engines with rubbers.

The unit comprises a solid-state thermostat with 1 slot hermetically sealed reaction vessel 2 (steel bomb). To control the tightness of the installed pressure gauge 3. In the reaction container 2 is placed the glass 4 with the test fuel, in which between the clamps have a rubber ring 5 (diameter 12 mm). The upper clamp 6 is a circular disk with a Central hole through which passes a steel string 7. The clip 6 is attached to the bottom end of the pipe 8. The pipe 8 is rigidly fixed to the cover 9. The upper end of the pipe 8 in turn is go enshrined in the power slot of the frame 10. The 7 string one end of which is attached to the lower clamp 11, made in the form of a solid disk on the upper side of which has a circular groove for placement of the rubber ring 5. The depth of the grooves is selected to ensure maximum axial deformation of the rubber ring 5 to 15% of the diameter of its cross section. The upper end of the string 7 is connected with one arm of the rocker arm 12, through the center of which passes the axle fixedly mounted on the power frame 10. To the other arm of the rocker arm 12 attached rod 13 by measuring the compression force of 14 (any load). On the output shaft of the electric motor 15 is fixed to the Converter 16 of the rotational motion of the shaft into reciprocating posturalnoe movement of the rod 13 (for example, a pair of screw-nut). The moment of reaching the specified maximum allowable axial deformation is controlled by the contact sensor 17 (any sensor push action, such as MP-3-3)mounted on the lower clamp 11. The value of the effort of compression corresponding to this time is recorded by the load cell 14. Measurement of temperature in thermostat 1 is performed by the sensor 18. The control motor 15, the measurement of the force Picompression, maintaining the set temperature t of thermostat with an accuracy of ±0,5°With fixation of the point of contact f is a block 19, the design of which R is developed using standard electronic components, converts incoming analog signals to digital, suitable for recording data in the personal computer 20 (any PC with a configuration that allows you to use the operating system is at least WINDOWS 95).

The method of assessing the compatibility of fuels for jet engines with rubbers as follows.

As in the prototype, for the extraction of antioxidant from rubber samples in the form of regular rings (prototype - blades) pre-incubated at a temperature of 150°C for 4 h in paraffin hydrocarbon with 12-16 carbon atoms, such as cetane, in an atmosphere of neutral gas is nitrogen or argon.

Later in the glass 4 pour 50 cm3the test fuel and put it into the reaction vessel 2. Disconnect the clip 11 from 7 strings. Prepared (after extraction of antioxidant) rubber ring 5 is installed in the annular groove of the clamp 11, and then fasten clamp 11 on the lower end of the string 7, which is placed in the pipe 8, is fixed in the cover 9. The cover 9 mounted on the reaction tank 2, resulting in the clamps 6, 11 with a rubber ring 5 are immersed in the test fuel. Then, the reaction container 2 is inserted in thermostat 1. Connect the upper end of the string 7 with the shoulder of the rocker arm 12 and the upper end of the tube 8 is fixed to the power carcase.

Include a control unit 19. Run the program process control tests on the PC 20. Establish communication control unit 19 with the personal computer 20 via the program menu.

Press the start button in the program window, then load ring 5 to the maximum allowable axial deformation δ=15% (limited by sensor 17). Record the values of the compression force of the rubber ring 5 in the PC 20.

Determine the temperature of T test equal to 145°and heat thermostat up to this temperature.

The process control tests produce in the viewer program pages Schedule effort" and "temperature Graph". The temperature deviation from the target should not exceed 0.5°C.

Record the start time test t1. During the test, periodically load the rubber ring 5 to the setpoint axial deformation δ=15% of the diameter of its cross-section and record the current values of the compression force of (Pi).

After the stabilization of the compression force of the rubber ring 5 (approximately Δτ=4 h) since the beginning of the tests produce stop the process by pressing the appropriate button in the program window. Off thermostat and remove the reaction capacity.

In accordance with the program and fixed values of Rmax- maximum led the ranks of compression efforts, N; Rmin- the minimum amount of force compression, N.; Δτ - the length of time reduction efforts compression of the sealing ring from the maximum to the minimum value, including Calculates the reduction rate of the compression efforts by the formula:

Compare it with the specified (0,9≤Wn≤2) and make a conclusion about the compatibility of the fuel with rubber.

Example 1: Ring ⊘12 mm diameter 2 mm of rubber IRP-1078 (TU 380051166) passed at a temperature of 150°C for 4 h in cetane (paraffin hydrocarbons with 12 carbon atoms) in an argon atmosphere (neutral gas) for the extraction of antioxidant from rubber (as in the prototype). Thus the process carried out artificially lowering the protective properties of the ring. Glass poured 50 cm3the test fuel TS-1 (GOST 10227) and put him in a reaction chamber. Prepared rubber ring installed between the clamps and placed in a reaction chamber. The reaction container is inserted in thermostat. Connected the upper end of the string with the shoulder of the rocker arm and the upper end of the tube is secured on the power frame.

Included control unit and launched a program of process control tests on the PC. Recorded values of the compression force of the rubber ring in the PC.

Set the temperature T test, equal to 15° With, and heated thermostat up to this temperature.

Recorded the start time test t1. During the test, periodically loaded rubber ring to the setpoint axial deformation δ=15% of the diameter of its cross section and recorded current values of compression efforts (Pi).

After reaching stabilization efforts compression rubber rings (via Δτ=4 h) since the beginning of the test stopped test.

In accordance with fixed values and maximum values of the compression force of Pmax=97,0 N, the minimum value of the compression force of Pmin=91,0 N, the length of time reduction efforts compression of the sealing ring from the maximum to the minimum value Δτ=4 h calculated reduction rate of the compression efforts by the formula:

The resulting value of the metric compatibility compared with the specified range (0,9≤Wn≤2) and concluded that the compatibility between the rubber with the given sample of jet fuel.

The claimed method and method prototypes were tested samples of jet fuel, and mixtures thereof, various technologies of production and composition (table 1).

As can be seen from the results shown in table 1, the inventive method allows to reliably differentiate fuels in terms of their aggressiveness towards rubbers is, what is very important due to the wide dissemination in the production of jet fuel processes "soft" Hydrotreating, which do not involve the introduction of a fuel-oxidant additives and mixing with straight-component fuels, but increase aggressive impact on RTI.

The inventive method correlates well with the way the prototype, however, in some cases (sample No. 3) allows us to reject the fuel, the use of which can lead to a significant reduction in resource, the rubber o-rings in the fuel system.

Table 1

The results determine the compatibility of jet fuel with nitrile rubber IRP-1078* declare and method prototype
№ p/pThe fuel samples**Method-prototype (sample of rubber in the shape of the shoulder)The proposed method (sample rubber - ring)
Elastic strength properties of the sample rubber IRP-A (target/actual)ConclusionMeasured parametersCompatibility rate Wn=(Pmax-Pmin)/ Δτ, H/hThe o***
Tear resistance, σ, kg/cm2Elongation, ε,%The force of the compression rubber ringsΔτ, h
Pmax, NPmin, N
1Arr. No. 1≥85/109≥100/145compatible97,091,041,50compatible
2Arr. No. 2≥85/40≥100/76incompatible82,080,840,30incompatible
3Arr. No. 3≥85/95≥100/100compatibleof 87.0of 83.440,75incompatible
4Arr. No. 4≥85/124≥100/181compatible118,5112,141,60compatible
5Arr. No. 5≥85/132≥100/175compatible122,0to 114.441,90compatible
*Resi is and mark the IRP-1078 most widely used in the production of rubber for aircraft turbine engines.

**Sample # 1 - jet fuel TS-1 (GOST 10227) direct distillation;

Sample # 2 - component hydrotreated fuel RT (straight-run kerosene fraction of crude oil which has passed the process of hydrocracking);

Sample # 3 is a mixture of straight run and components hydrotreated jet fuel TS-1 in the ratio 10:90.

Sample # 4 - hydrotreated fuel RT (GOST 10227) with antioxidant additive "Ionol" at a concentration of 0.003 wt.%.

Sample # 5 - fuel obtained by deep hydrogenation of T-6 (GOST 12306).

***we believe that the aviation fuel is compatible with 0,9≤WH≤2.

The proposed method was tested for compatibility with rubber IRP A samples of fuels. The results were compared with the results of the operation of specific aircraft GTE. Table 2 shows the results of these tests. The data in table 2 allow us to conclude about the presence of the correlation between the indicator of operational properties (column 3) by the present method and resource (column 4) of the real RTI in the fuel systems of the CCD.

Really after operating engine 50-70 h at RT fuel without antioxidant additives was observed mass failures of the fuel injection units, expressed in violation of their integrity. Visual inspection were the detection of whom were cracks on the surface of the sealing rubber rings. When testing this fuel claimed by way of the value of the metric compatibility of the fuel with rubbers (WH=0,4 N/h) has gone beyond the lower boundary of the proposed allowable range (0,9≤Wn≤2).

Table 2

The results of the comparison aggressive on RTI in the natural environment and by the claimed method
№ p/pFuelCompatibility rate Wn=(Pmax-Pmin)/Δτ, H/hThe resource of mechanical rubber goods, rubber IRP-A in full-scale tests on aircraft, hThe state RTI
1Base fuel RT (without antioxidant additives)0,450-70Cracking RTI and loss of elasticity
2TS-1 (straight-line)1,82000-5000Failures due to defects RTI is not awarded
3Naphthyl0,6100Marked destruction of RTI during benchmark testing

Thus, the application of the proposed method increases the accuracy of determining the compatibility of jet fuel with RTI at the expense of close to operating conditions. In addition, the value of the designated pokazatel is possible to draw conclusions about the resource of RTI in the fuel systems of aircraft GTE when using different samples of jet fuel.

The proposed method allows to study the dynamics of change in properties of a sample of rubber (rings) in collaboration with the heated fuel. The proposed method is simple to implement and requires more complex equipment that reduces the cost of testing.

The method of assessing the compatibility of fuels for jet engines (jet fuel) with rubber used in the fuel systems of aircraft gas turbine engine (GTE)including serial endurance rubber samples within 3-5 h in paraffin hydrocarbon with 12-16 carbon atoms in the atmosphere of neutral gas in the test fuel at a temperature of 130-150°in sealed containers for at least three hours, characterized in that as the sample use rubber o-ring fuel system GTE, set the maximum value of its axial deformation when contacting the sealing ring with the test fuel at a temperature of 130-150°occasionally load it up to the specified maximum axial strain at the end of each period of loading fix the compressing force, the test finished at the time of stabilization efforts compression ratio, fixed length of time reduction efforts compression ratio of maximum Rmaxto the minimum Rminvalues, calc is jut speed reduction efforts compression by the formula:

,

where Wh- speed reduction efforts compression ratio, H/h;

Pmax- the maximum value of the compression force of the sealing ring to a specified maximum allowable axial deformation, H;

Pmin- the minimum value of the compression force of the sealing ring to a specified maximum allowable axial deformation, H;

Δτ - the length of time reduction efforts compression of the sealing ring from the maximum to the minimum value, h,

and when the values of 0.9≤Wh≤2,0 consider fuel for jet engines compatible with rubber.



 

Same patents:

FIELD: investigating or analyzing of materials.

SUBSTANCE: method comprises investigating threshold capabilities of the multi-layer polymeric material and determining maximum permeability of oil product and time period required for reaching the maximum permeability.

EFFECT: enhanced reliability.

1 dwg, 1 tbl

FIELD: light industry.

SUBSTANCE: method comprises recording response of the material to be tested that represents an amplitude-frequency characteristic, calculating deformation characteristics, and determining the value of distributed mass of the vibrating part of the material. The response representing two amplitude-frequency characteristics is recorded for the same part of the material to be tested for various masses of two bodies that cause deformation. The deformation characteristics are calculated from equations of vibration theory for viscoelastic bodies.

EFFECT: enhanced precision and reliability.

FIELD: weighing equipment; chemical mechanical engineering.

SUBSTANCE: method can be used for measuring content of binder in reel-up composite material produced by preliminary soaked thread. Method is based upon weighing. The constant values are determined according to the method as length of thread for specific type of items and value of linear density averaged for any reel before and after soaking by binder and reeling it up onto frame. Weighing is performed for item before reeling it up with soaked thread and after reeling-up and final polymerization of composite material to determine mass of composite. Basing upon the data received, content of thread is determined which value is subsequently used for finding mass content of binder in composite from relation of C=(M-LxT/M)x100%, where C is content of binder in composite, in mass percent; M is mass of composite, g; L is length of thread consumed for item, km; T is average arithmetic meaning of values of linear density of thread and its rests at any reel before and after impregnation, g/km.

EFFECT: higher stability of performance measures.

1 ex

FIELD: investigating or analyzing materials.

SUBSTANCE: method comprises preparing specimens of polymeric materials of specified mass, exposing the specimens to the hostile fluid at a given temperature, and determining informative characteristic from a formula proposed.

EFFECT: enhanced reliability.

2 dwg, 7 tbl, 2 ex

FIELD: technologies for researching durability properties of packing washer materials for collapsible oil pipelines.

SUBSTANCE: in the method for determining remaining resource of rubber compacting curves utilized in oil pipeline junctions, preparation of samples of given geometrical shape is performed, measurement of source hardness conditions for stretching, relative elongation during tearing, Shore hardness, temperature fragility limit, comparison of aforementioned values to given values, culling of washers, sample coefficients of which do not correspond to given values. Remaining samples are exposed to oil product after extraction from oil product samples are thermostatted, cooled down to normal room temperature, and then the same physical-mechanical coefficients are measured again with limit values. Before preparation of samples with given geometrical shape, washers are organized in batches of same manufacturing plant and production year, additionally measured are external d1 and internal d2 washer diameters for each batch, relative compression Ecp deformation of same washers. Their deviation from standard is calculated and culling of aforementioned washer batches is performed on basis of allowed values Δd1, Δd2 and Ecp, while as allowed values Δd1, Δd2 ≤ 3%; 25% ≤ Ecp ≤ 70%. After that remaining rings with least values of relative compression deformation Ecp are utilized to prepare geometrical samples of given geometrical shape. Remaining resource ΔT is determined from following formula: years, where ki - coefficient, characterizing alteration of remaining resource ΔT dependently on climatic zone input of operation of rubber packing washers, is taken as i - climatic zones I1 - II12, additional information, T - average lifetime of rubber packing washers until removal from operation in accordance to technological characteristics provided by manufacturing plant and/or operation instructions, in years, Tn - period of operation of rubber packing washers since production year - marking of manufacturing plant, until moment of determining ΔT, years, f=9,4 MPa - minimally allowed value of conditional hardness for stretching after thermostatting of sample, MPa.

EFFECT: reliable trustworthiness of results of estimation of remaining resource under dynamic conditions of rubber packing washers in oil pipeline junctions with simultaneous increase of ecological safety due to decreased risk of emergency spilling of oil products.

4 dwg

FIELD: agriculture, in particular, dairy farming.

SUBSTANCE: method involves determining tightening of teat cup liner before it is inserted into teat cup; acting upon teat cup liner by suspending weight for determining tightening of teat cup liner; providing expansion by introducing internal gauge into teat cup liner which is positioned within teat cup casing. Method allows extent of teat cup liner tightening to be visually detected at any time of machine milking process. Tightening of teat cup liner manufactured integral with milk pipe as well as separately therefrom is determined during operation of milking units.

EFFECT: increased efficiency and reduced milking time.

1 dwg

FIELD: methods and devices for determination of an alcohol concentration in solutions.

SUBSTANCE: the invention presents a method of determination of an alcohol concentration in solutions (versions) and a device for its realization (versions). The first version of the method provides for placement of a bath with the reference and investigated solutions on the path of the optical beam, measuring and introduction into the memory of the computation unit of intensity of the light absorption by the reference solutions, measuring of the intensity of the light absorption of radiation of the investigated solution, processing the data of the measurements of the light absorption. The investigated solution is transilluminated within the range of the wavelengths of 1250-1350 nanometers. Simultaneously with the measurement of the light absorption by the investigated solution measure the concentration of alcohol in it. In compliance with the received values determine a concentration of alcohol in the investigated solution. The second version of the method provides for placement of a bath with the reference solutions and investigated solutions on the path of the optical beam, measurement and introduction into the memory of the calculation device of intensity of the light absorption of radiation by the investigated solution, processing of the received values of the measurements of the light absorption. The investigated solution is transilluminated within the range of the wavelengths of 1250-1350 nanometers, measure the values of density of the reference solutions and the investigated solution, using which determine the concentrations of alcohol and sugar in the investigated solution. The device for the first version contains a computation unit, a conjunction unit, optically coupled a radiating unit, a bath for solution, a measuring photoreceiving device, the output of which is connected through the conjugation unit with the computation unit and the input of which is optically connected through the bath with the radiating unit. The device for measurement of a concentration of sugar in a solution consists of a beam splitter plate and an additional photoreceiving device, the output of which is connected through the conjugation unit with the computation unit. The input of which is optically connected through the beam splitter plate mounted at Brewster's angle to a axis of radiation and the bath with by a radiation unit. And the radiation unit has the wavelength of radiation laying within the range of 1250-1350 nanometers. The device for determination of a concentration of alcohol in the solutions consists of the computation unit, the conjugation unit, the optically connected radiation unit, the bath for solution, the measuring photoreceiving device, output of which is connected through the conjugation unit with the computation unit, the density gage connected with the bath by means of the pipe duct. The output of the density gage is connected through the conjugation unit with the computation unit. The radiation unit has the wavelength of radiation laying within the range from 1250 to 1350 nanometers. The invention allows to improve accuracy of measurements.

EFFECT: the invention ensures an improved accuracy of measurements.

12 cl, 5 dwg

FIELD: fur industry, in particular, method for evaluating pickling quality of leather web in tanning of fur and sheepskin raw material.

SUBSTANCE: method involves determining quantitative pickling characteristic of leather web of semi-finished product by using time of solving thereof in alkaline solutions, said time depending on number and kind of intermolecular bindings destructed during pickling. Solving of collagen in alkaline solutions depends upon nature of preliminary acidic preparing procedure. Solving is provided in aqueous solution of potassium hydroxide having concentration of 150 g/l and temperature of 18-20 C. Derma solving time is found after preliminary thermal processing at temperature of 60-65 C during 1.5 hours. Method may be employed both in production of fur and sheepskin products and in fur processing.

EFFECT: wider operational capabilities and reduced time for determining quantitative pickling characteristic of skin web.

1 tbl, 1 ex

FIELD: fur industry, in particular, method for evaluating pickling quality of leather web in tanning of fur and sheepskin raw material.

SUBSTANCE: method involves providing testing on parallel groups of fur sheepskin after pickling on three topographic portions of sheep skin surface: skirt, spine and neck portions; processing samples of each group with acid-salt solution for 24 hours; withdrawing sheepskins of each group from acid-salt solution in predetermined time intervals; removing excessive liquid; placing said samples into tensile testing machine and stretching lengthwise of spine line by 40% relative to initial length thereof; holding samples in stretched state for 1 min and withdrawing from tensile-testing machine; leaving samples in free state for 10 min; determining residual elongation value in mm.

EFFECT: reduced time for determining quantitative pickling characteristic of skin web.

2 tbl, 2 ex

The invention relates to methods for the study of strength properties of materials o-rings pipe connections, for example, type “Socket” and can be used to determine the timing of replacement of sealing pipe joints

FIELD: investigating or analyzing of materials.

SUBSTANCE: method comprises investigating threshold capabilities of the multi-layer polymeric material and determining maximum permeability of oil product and time period required for reaching the maximum permeability.

EFFECT: enhanced reliability.

1 dwg, 1 tbl

FIELD: chemical technological processes for producing solid fuel, possibly in coal-tar chemical industry for selecting coal charges for coking.

SUBSTANCE: method for determining optimal composition of stable type coal charge for coking comprises steps of receiving reference charge; calculating and determining optimal composition of charge; preparing charge with optimal content of its components for further coking while performing all investigation processes in industrial coke ovens; taking as reference charge several types of charge with different composition; preliminarily selecting large number of reference basic types and admissible relations of components for each type of charge; according to data of passive or active experiments plotting inlet-outlet model of fluctuations of coking process for each type of charge; adjusting relay- exponential predicting device; effectively measuring coal masses present in silos and towers of coal-tar chemical production; measuring current properties of coal charge components for coking, current parameters of coking mode, type and content of charge of previous day, selected for usage type and components of charge for future operation period of coke batteries. If both types of charge are matched, according to history data for selected type of charge, finding sampled variations of percentage content of each component of charge; ranging found row of variations; in said ranged row selecting stable components of charge with less value of variations among non-stable components with high value of variations in order to provide realization of relation 2 ≥ nc/ni≤ 1 where nc - number of stable components; ni - number of non-stable components that is to be no less than 2; setting mass values of stable components of charge according to levels of previous operation period of coke ovens; predicting coke quality by means of relay-exponential predicting device; finding deviation of predicted value of coke quality factor from predetermined one; in inlet-outlet mathematical model of coking process with use of regular or irregular searching procedures, optimizing relations of non-stable components in order to provide equality of both values (predicted and predetermined ones); combining found relations of non-stable components with predetermined relations of stable components in order to provide optimal composition of charge.

EFFECT: possibility for obtaining results of optimization of coal charge composition almost equal to parameters of actual production process, improved reliability of accelerated optimizing process, possibility for predicting coke quality.

1 note, 1 tbl, 1 dwg

FIELD: investigation of liquid hydrocarbon fuels.

SUBSTANCE: method comprises steps of mixing sample of analyzed fuel composition with distillate component till viscosity (2.0 ± 0.1)mm2/s at 100°C; dividing prepared mixture by two parts; heating them till temperature (100-110)°C; then cooling first part till 20°C; soaking at such temperature for 24 h and subjecting it to centrifuge processing at temperature (30±2)°C for 60 min; determining value of separated deposit; cooling second part till temperature (60±2)°C; subjecting it to centrifuge processing at such temperature for 45 min; determining value of deposit and calculating factor of fuel stability.

EFFECT: enhanced accuracy of calculating stability factor of fuel systems.

4 tbl

FIELD: analyzing or investigating materials.

SUBSTANCE: method comprises measuring density of gasoline, dielectric permeability of gasoline at the first frequency, measuring absorbing of acoustical energy in gasoline, measuring specific conductivity of gasoline and dielectric permeability at the second frequency, determining the ratio of the values of dielectric permeability for two different frequencies, temperature correcting of the parameters measured, and calculating the octane number with the use of a calibration model.

EFFECT: enhanced precision.

2 dwg

FIELD: the invention refers to measuring technique.

SUBSTANCE: the system of marking of hydrocarbon fluid medium running from the source to the designated place has at least one sensor for definition of at least one property of the flowing medium, at least one regulator of consumption of the marker for intake of the prescribed quantity of the marker into the flowing medium at least from one source of the marker. The property of the flowing medium is chosen out of the group including temperature, consumption, viscosity, density and concentration. A processor is switched at least to one sensor and at least to one regulator. The processor defines the prescribed quantity of the added marker (diluted in this case) in correspondence with the property of the flowing medium and the prescribed concentration of the marker in the flowing medium and controls the regulator of at least of one marker. The invention allows to identify oil. petrol, kerosene, different kinds of fuel for evaluation of conservation of the initial quality(dilution, falsifications) of the spill or leakage of liquid hydrocarbons from pipe-tubes, tankers or storehouses.

EFFECT: identifies different kinds of liquid hydrocarbons.

70 cl, 10 dwg

FIELD: explosives and mine-torpedo weapon charges.

SUBSTANCE: the method consists in modeling of the processes of detonation and energy liberation occurring at a burst of various composite charges, according to the affecting factors of an underwater burst of a composite charge, comparative analysis of their quantitative characteristics. At modeling of the processes of detonation and energy liberation the interaction of the underwater burst with the environment and the protective structure multichamber in depth is modeled, the gauge pressure, pressure pulse, density of the energy flux and hydroflux are used as characteristics of the affecting factors of an underwater burst.

EFFECT: provided determination of the most effective crater effect of the charge composition of the up-to-date mine-torpedo weapon intended for accomplishment of a short-range contact and non-contact burst.

3 dwg, 1 ex

FIELD: analytical methods in petroleum processing industry.

SUBSTANCE: invention is intended as a means for metrological provision of measurement procedures in determination of iodine number of light petroleum products. Standard sample involved is a mixture containing 0.04-4.0% liquid olefinic hydrocarbon and 99.96-96.0% aliphatic alcohol. Iodine number range in above analyses is between 0.1 and 6 g I2/100 g.

EFFECT: enabled reliable evaluation of quality of light petroleum products wherein quantitative content of unsaturated hydrocarbons is determined according to requirements of normative-technical documents.

FIELD: gas metering methods and devices.

SUBSTANCE: gas meter includes heat flow rate pickup for determining mass flow rate and heat quality pickup for determining type of gas. Heat gas flow rate pickup and(or) heat gas quality pickup are in the form of CMOS -anemometers having heating member and temperature pickups arranged upstream or downstream from heating member relative to gas flow direction; they may be in the form of single pickup. In variants of invention it is possible to measure heat conductance, heat capacity, diffusion capability or viscosity of gas or gas mixture for determining type of gas. At presence of combustible gas or gas mixture counter operates with calibration in units of mass or volume in standard condition. At presence fuel gas and or gas mixture said counter operates with calibration in units energy.

EFFECT: improved accuracy of metering consumed energy due to automatic identification of gas type, of trials of manipulations with counter, possibility for automatic tracking heat capacity without its direct measuring.

14 cl, 4 dwg

FIELD: explosives.

SUBSTANCE: group of invention relates to marking explosives and can be used to identify explosives and manufacturing place. To that end, a method for revealing an explosive and a marker to reveal explosive. Method comprises preparation of explosive with a marker uniformly distributed therein. Marker is made in a manner to have information field enabling further reveal and identification of explosive or explosive and manufacturing place thereof during its storage period or during its storage period and after blast of explosive. Marker is made from material having hardness no higher than that of explosive and information field is of holographic nature.

EFFECT: increased information value of marker without deterioration of explosive characteristics.

28 cl, 1 tbl

FIELD: petroleum product test methods.

SUBSTANCE: invention relates to petroleum product testing area and mainly to evaluation of chemical stability of motor gasolines to provide methods applicable in research institutions, in refinery laboratories, and at enterprises dealing with development and application of motor fuels as well as with problems concerning preservation of automobile gasolines during storage and transportation periods. In a method of evaluating induction period of motor gasolines from sample oxidation time at 100°C calculated in terms of a mathematic relationship using an informational parameter of the sample, the latter is content of unsaturated hydrocarbons Cn, which is preliminarily determined in the sample, and sample oxidation time at 100°C (τ100) is calculated in terms of following relationship: τ100 = k1Ln(Cn)+k2, where k1 and k2 are empirical constants.

EFFECT: accelerated motor gasoline induction period evaluation without reduction in requirements to accuracy and reliability and increased determination safety.

1 dwg, 3 tbl

FIELD: investigating or analyzing materials.

SUBSTANCE: method comprises determining the values of the inform-parameter for various reference petrols, plotting calibration dependence of the inform-parameter on the octane number, determining the value of the inform-parameter of a sample of petrol to be analyzed, determining octane number of the petrol to be analyzed from the calibration curve, and measuring density and temperature of the sample. The value of the inform-parameter is determined from measuring the surface tension of the sample. The octane number is calculated within temperature range 10-40oC.

EFFECT: enhanced accuracy of determining.

1 tbl cl, dwg

Up!