scholarly journals Determination of the time of ignition of plant raw under the high temperature of the radiation panel

2020 ◽  
Vol 11 (3) ◽  
Author(s):  
V. V. Lomaha ◽  
O. Yu. Tsapko ◽  
Yu. V. Tsapko ◽  
O. P. Bondarenko

Reducing the fire prevention of timber is not only an economic task, but also has a social and environmental focus. From economic, technological and environmental perspective, an important problem in ensuring the viability and safe operation of construction sites is the development of fire-retardant coatings for wooden structures. The construction is increasingly looking for new highly effective means of fire protection of wood and wood products which should not only ensure the standardized fire resistance of wood, but also to maintain its operational parameters to solve environmental safety and durability. Studies of the effect of the radiation panel on the ignition of the wood sample have set the parameters of the flame ignition, which makes it possible to influence this process. It is proved that they consist in the formation of a layer of organic material on the surface, which provides heating to a critical temperature, when the intensive decomposition of the material begins with the release of the required amount of combustible gases and their ignition. This makes it possible to determine the effect of fire protection and the properties of protective compositions on the process of slowing down the rate of burning of wood. Experimental studies have confirmed that the untreated sample of wood, under the thermal action of the radiation panel has taken up, the flames spread over the entire surface, which led to its combustion. The application of a fire retardant varnish under the influence of temperature leads to a layer of foam coke and inhibition of heat transfer of high-temperature flame to the material and its ignition. Thanks to this, it became possible to determine the conditions for changing the parameters of combustion and braking during fire protection of wood, by forming a barrier for thermal conductivity. Thus, there is reason to argue for the possibility of directional control of the processes of fire protection of wood by the use of fireproof coatings that can form a protective layer on the surface of the material, which slows down the rate of burning of wood.

Author(s):  
Yu. Tsapko ◽  
◽  
А. Tsapko ◽  
O. Bondarenko ◽  
V. Lomaha ◽  
...  

Abstract. The processes of creation of fire-retardant varnish for wood consisting of a mixture of inorganic and polymeric substances are investigated in the work. It is established that the optimization of the inorganic component leads to a directional ratio of mineral acids and urea capable of effective fire protection of the material. Studies have shown that at the initial temperature of gaseous combustion products T = 68 °C, when exposed to the radiation panel, the untreated sample ignited after 146 s, the flame spread over the entire surface, instead, the sample fire-protected varnish did not ignite, the maximum temperature was 105 °C. In this case, as evidenced by the results of heat resistance, there is a change in the structure of the protective film of the coating. The thickness of the protective layer increases due to the decomposition of the composition, which leads to inhibition of oxidation in the gas and condensed phase, change the direction of decomposition towards the formation of non-combustible gases and combustible coke residue, reduce material combustion and increase flammability index. The coating under the influence of high temperature promotes the formation of a heat-insulating layer of coke, which prevents burning and the passage of high temperature to the material, which is confirmed by the absence of the process of ignition of fire-retardant wood. Features of braking of process of ignition and distribution of a flame of the wood processed by a varnish which consist in several aspects are established. This is the formation of a heat-insulating layer of coke, which prevents burning and the passage of high temperatures to the material, which is confirmed by the absence of the process of ignition of fire-retardant reeds. This indicates the possibility of targeted control of high temperature transfer processes to organic material through the use of special coatings for wood products.


2021 ◽  
Vol 2 (10 (110)) ◽  
pp. 51-58
Author(s):  
Yuriy Tsapko ◽  
Roman Vasylyshyn ◽  
Oleksandr Melnyk ◽  
Vasyl Lomaha ◽  
Аleksii Tsapko ◽  
...  

The analysis of fire-protective materials for wooden building structures was carried out and the need to develop reliable methods for studying the process of washing out fire retardants from the surface of the building structure, which is necessary for the creation of new types of fire-protective materials, was established. That is why there arises a need to determine the conditions for the formation of a barrier for washing out and to establish a mechanism for inhibition of moisture transmission to the material. In this regard, a mathematical model was built of washing out fire retardants using a polymeric shell made of organic material as a coating, which makes it possible to estimate the effectiveness of a polymer shell by the amount of the washed-out fire retardant. According to the experimental data and theoretical dependences, the dynamics of the release of fire retardants from the fire-protective layer of the coating was calculated; it did not exceed 1.0 %, and therefore, ensures fire protection of timber. The results of determining the weight loss of the sample under the influence of water indicate the ambiguous impact of the nature of protection on the washout. In particular, this implies the availability of data sufficient for performing a high-quality process of moisture diffusion inhibition and, based on it, detection of the moment, from which a decrease in efficiency of a coating begins. The experimental studies proved that a sample of fire-protected timber after exposure to water for 30 days withstood the influence of a heat flow. In particular, the loss of timber weight after the temperature exposure was less than 6 %, and the temperature of flue gases did not exceed 185 °C. Thus, there is a reason to assert the possibility of directed control of the processes of fire protection of timber through the use of polymer coatings capable of forming a protective layer on the surface of fire-protected material, which inhibits the rate of washing out the fire retardants


Author(s):  
Stephen R. Swartz

Since the inception of the cyclone style boiler, industry has become accustomed to performing routine maintenance during every scheduled shutdown occurring 12 months to 18 months between cycles. These maintenance cycles are influenced by service factor, loading and the type design. The same problems exist in both the standard and super critical cyclones; severe deterioration of refractory and the anchoring pin studs. This paper focuses on one type of refractory failure mechanism caused by the anchoring pin studs. Most operators have found that the most effective means of applying refractory in this type situation is to “ram” the refractory in and around the anchoring pin studs thus creating a dense lining with maximum integrity. Coupled with proper application of anchoring pin studs and a special designed coating, typical volumetric expansion of the pin studs from corrosion attack and oxidation is eliminated thus extending the life of the refractory. This mechanism is discussed along with the results of the coating performance as it relates to extreme heat oxidation and thermal cycling in laboratory tests. A protective coating was developed using a nano-cored thermal spray wire technology that produces a uniform, adherent protective layer against high temperature corrosion and oxidation. The coating yields similar thermal conductivity as a bare stud thus experiencing excellent thermal cycle performance. This specially designed thermal spray coating is applied to standard 430 stainless steel pin studs thus providing the necessary barrier against aggressive high temperature environments while maintaining excellent heat conductivity. The coating has a high amount of tungsten (40+%) in a nickel matrix with greatly reduced oxides at the substrate and throughout the coating. With these attributes for the anchoring pin studs in mind, a newly designed stud was evaluated in heat oxidation tests up to 2000°F and thermal cycling test and compared to 430 stainless steel, chromized and Alloy 625. The new stud out-performed all others even in the as-welded condition. Further corrosion testing in ferric chloride (ASTM G48) showed them to be superior to Alloy 72 and Alloy 625 in the thermal spray and welded condition. Proper welding equipment and welding techniques are also discussed since weld continuity impacts overall performance of anchoring pin studs with refractory linings. A major test site will be examined in the spring of 2004 for it’s full effectiveness in service and will be documented in order that all data retrieved would be available to the entire industry.


2012 ◽  
Vol 594-597 ◽  
pp. 849-859
Author(s):  
Man Li Ou ◽  
Wei Jun Cao ◽  
Long Min Jiang ◽  
Hui Cao

As the result of great changes occurring to mechanical properties under high temperature (fire) conditions, steel structures will soon lose the strength and stiffness and lead to structural damage. Through analysis of the steel structure fire resistance design methods under the conditions of high temperature (fire), this article explores the most used fire protection methods in steel structures—brushing or painting fire-resistant coatings, studies the fire-resistance theory of steel structure under fire conditions; in addition, the author proposes the reasonable thickness of the steel structure fire retardant coating of fire-resistant design through design examples.


2021 ◽  
Vol 4 (10(112)) ◽  
pp. 45-51
Author(s):  
Yuriy Tsapko ◽  
Zinovii Sirko ◽  
Roman Vasylyshyn ◽  
Oleksandr Melnyk ◽  
Аleksii Tsapko ◽  
...  

This paper reports an analysis of the flame retardants for fabrics that has revealed the fact that the meagerness of data to explain and describe the process of fire protection, specifically the neglect of elastic coatings, leads to that the structures made from fabrics are ignited under the influence of a flame. Devising reliable methods to study the fire protection conditions for fabrics results in the design of new types of fireproof materials. Therefore, there is a need to determine the conditions for the formation of a barrier for water mass transport and to establish a mechanism for slowing down water penetration through the material. In this regard, an estimation-experimental method has been constructed for determining mass transfer under the action of water when using a hydrophobic coating, which makes it possible to assess water penetration. Based on the experimental data and theoretical dependences, the intensity of mass flow under the action of water has been determined, which is 0.000177 kg/m2, which ensures fabric resistance. The study results have proven that the process of waterproofing the fabric involves inhibition of the mass transfer process under the action of water by insulating the surface of the fireproof fabric with a hydrophobic coating. It should be noted that the presence of a hydrophobic coating leads to blocking the fabric surface from moisture penetration. Such a mechanism behind the effect of the hydrophobic coating is likely the factor in adjusting the process through which the integrity of an object is preserved. Thus, the sample of fireproof fabric coated with a water repellent demonstrated, after exposure to water, that the amount of water absorbed did not exceed 0.00012 kg, and, for a fabric without a water repellent, was 0.01 kg. Thus, there is reason to assert the possibility of targeted adjustment of the processes related to water penetration of the fabric by using hydrophobic coatings that could form a protective layer on the surface of the material, which inhibits the rate of water penetration.


2021 ◽  
Vol 264 ◽  
pp. 02065
Author(s):  
Tatiana Budykina ◽  
Yevgenia Anosova

The results of experimental studies of the behavior of fireproof materials of Russian production – OGNEZA-LTU, OGNEZA-M-KOR, OG-NEZA-M-KOR (NG), «OGNEBAZALT» PMBOR, OGNEZA-GT under thermal action are presented. Research method – synchronous thermal analysis TG/DCS/dDSC, including differential scanning calorimetry (DSC) and thermogravimetry (TG). Experimental conditions on the NETZSCH thermal analyzer: measurement mode – TG/DCS/dDSC; heating rate: 20 °C /min; heating – up to 1000 °С; atmosphere – N2. The rates of weight loss of the investigated fire-retardant materials have been studied. A high rate of weight loss was established for the OGNEZA-LTU samples (20.5 %/ min at 335 °C) and OGNEZA-GT (11.9 %/min at 369 °C); low – OGNEZA-M-KOR (NG) – 1.7 %/min at 349 °C, OGNEZA-M-KOR – 6.1%/min at 341 °C, «OGNEBASALT» PMBOR - 3.5 %/min at 388 °С. Time intervals of weight loss were determined: all test samples had maximum weight loss in the range of 15-20 minutes. The temperature ranges of the maximum rate of weight loss were determined: 349 - 388 °C. The best heat-resistant properties were shown by OGNEZA-M-KOR (NG), «OGNEBASALT» PMBOR, OGNEZA-M-KOR. It is proposed to consider the revealed properties when using fire retardant materials for the constructive fire hazard of civil and industrial facilities.


Author(s):  
Yu. Tsapko ◽  
◽  
А. Tsapko ◽  
O. Bondarenko ◽  
M. Suhanevich ◽  
...  

The results of experimental studies on the effectiveness of fire protection of easily erected structures made of flammable textile products are presented. An analysis of the directions of use of easily erected structures made of flammable textile products indicates a steady trend towards an increase in their use during the temporary fulfillment of certain tasks of the Armed Forces of Ukraine and units of the. During the heating of such structures, ignition and rapid spread of fire are possible. The operating statistics for easily erected structures have found a low level of safety due to the use of natural fibers (e.g., linen, cotton and blends), which are highly sensitive to heat and fire. Reduction of combustibility and the development of non-combustible and non-combustible materials is one of the main directions for preventing fires and solving the problem of expanding the scope of these materials. Treatment with fire protection means significantly affects the spread of the flame, allows you to reduce the smoke-generating ability and heat release significantly. After the test, it can be seen that the sample of the textile material sustains spontaneous combustion for more than 5 s; sample damage is more than 150 mm. After the test, it is clear that the sample of textile material does not support self-combustion for no more than 5 s; sample damage is no more than 100 mm. The inhibition of the process of ignition and flame propagation for such a sample is associated with the decomposition of fire retardants under the influence of temperature with the absorption of heat and the release of incombustible gases (nitrogen, carbon dioxide), a change in the direction of decomposition towards the formation of incombustible gases and a hardly combustible coke residue. This leads to an increase in the thickness of the coke layer and inhibition of the heat transfer of the high-temperature flame to the material, which indicates the possibility of the transition of textile materials during processing with a fire retardant composition to materials that are non-combustible, which do not spread the flame by the surface.


2020 ◽  
Vol 1006 ◽  
pp. 32-40
Author(s):  
Yuriy Tsapko ◽  
Vasyl Lomaha ◽  
Olga P. Bondarenko ◽  
Maryna Sukhanevych

The effect of the composition on the weight loss of wood protected by a coating based on inorganic and organic substances in the process of thermal exposure, which is a feature of the study of the flame retardant effectiveness of the composition, is investigated. The solution of this problem is carried out by specially developed methods. The influence of fire protection under the influence of high-temperature heat flux on the change in the process of loss of mass of fire-protected wood is determined and the mechanism of kinetics of action of the composition is characterized, which is characterized by a decrease in the speed of flame propagation and mass loss. The results of thermogravimetric studies determined the weight loss of the coatings as a function of temperature, the results of which investigated the activation energy at the temperature decomposition of the coatings and found that for wood it was 36.56 kJ / mol, and in the case of fire protection it increased 2.3 times. which makes it possible to conclude that it is advisable to use lacquer varnish to improve the fire retardant efficiency of wood. Thus, for the specimen of fire-retardant lacquer wood, there is a gradual decrease in temperature, ie, the work of the coating is fixed, and, accordingly, the activation energy is increased during the decomposition of the wood. In order to establish the flame retardant efficiency in the application of high-temperature blowing lacquer, studies were conducted to determine the combustibility index of wood by mass loss, flame spread and temperature increase of flue gases and found that when processing wood goes to the group of combustible materials with a burning index.


Author(s):  
A. Kovalov ◽  
◽  
Y. Otrosh ◽  
V. Tomenko ◽  
O. Vasylyev ◽  
...  

Abstract. The results of the development of fire-retardant substances based on domestic materials to increase the fire resistance of fire-retardant steel structures are presented. New compositions of fire-retardant substances on the basis of domestic materials capable of swelling are developed. A series of experimental studies to determine the heating temperature of fire-resistant steel structures. For this purpose, samples of reduced size in the form of a steel plate with a flame retardant applied to the heating surface were used. Fire tests of fire-retardant steel plates coated with the developed fire-retardant substance forming a coating on the protected surface, in the conditions of their tests on the standard temperature of the fire using the installation to determine the fire-retardant ability of fire-retardant coatings. The results of experimental determination of temperature from an unheated surface of steel plates with a fire-retardant covering in the conditions of fire influence at a standard temperature mode of a fire are analyzed. Based on the obtained data (temperature in the furnace and from the unheated surface of steel plates with fire protection system) the solution of the inverse problems of thermal conductivity found thermophysical characteristics of fire protection coating (thermal conductivity and specific volume), which can be used for thermal calculation heating of fire-retardant steel structures at arbitrary fire temperatures. The thermophysical characteristics of the formed fire-retardant coating are substantiated to find the characteristics of the fire-retardant ability of the newly created fire-retardant coating and to ensure the fire resistance of fire-retardant steel structures. The efficiency of the developed fire-retardant coating for protection of steel structures is proved.


Author(s):  
T.A. Budykina ◽  
◽  
E.B. Anosova ◽  

The results are presented concerning the experimental studies of the behavior of fire-retardant seals produced by the Ogneza group of companies under thermal exposure up to 1000 °C, obtained by the method of synchronous thermal analysis (thermogravimetry together with the differential scanning calorimetry). Incombustible properties of the M-СORE (NG) seal were confirmed, which showed a decrease in the mass of the material when heated to 1000 °C by 11%, which is due to the mineral composition of the sample (a silica-based material). High thermal stability was shown by the fire-fighting seal M-CORE, the decrease in the mass of the sample of which, after reaching a temperature of 555 °C, stops at 37 %, which indicates the formation of an ash residue. Thermal sealing tape LTU, as a result of the temperature heating starting from a mark of 192 °C, uniformly was losing mass up to a total value of 82 %. The experiment established the sealant swelling. According to the experimental data obtained, the samples M-CORE (NG) confirmed the fire-retardant properties declared by the manufacturer. For the selection of heat-resistant materials that can withstand significant temperature loads during the operation of units and mechanisms, for electrical and thermal insulation, for fire protection of air ducts, equipment, structures, the advantages, and reliability of these seals are obvious. The results of the study (the temperature of the beginning of an intensive decrease in mass, the temperature of the onset of thermal effects accompanying a decrease in mass, the behavior of materials under thermal exposure) can be considered when designing heat and electrical insulation, fire protection of production processes, as well as when determining the level of fire risk of the production facilities.


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