Detection device and detection method for evaluating flame retardant property of facing fireproof coating

Abstract

The invention relates to the technical field of flame retardant property detection of fireproof materials, in particular to a detection device and a detection method for evaluating the flame retardant property of a facing type fireproof coating. According to the detection device, a combustion space close to an actual building environment is provided, on one hand, the state of the ventilation opening is adjusted through the electric louver, different ventilation conditions such as natural ventilation, mechanical ventilation or ventilation blocking when a fire occurs are simulated, and the coating is tested in various airflow environments; on the other hand, a heat radiation source is arranged to simulate a heat radiation environment around a material in a fire, non-uniform heat radiation intensity distribution is set to be similar to a real fire scene heat source complex condition, and the performance of the coating under different heat radiation conditions is tested. Besides, the gas mixer can dynamically adjust the oxygen concentration in the cabin according to the test requirement, so that the conventional oxygen index test is met, the oxygen content change in the fire process can be simulated, and the flame-retardant performance of the coating in the actual oxygen content fluctuation scene is explored.

Description

Technical Field

[0001] The present invention relates to the technical field of flame retardant performance detection of fireproof materials, and more specifically, to a detection device and a detection method for evaluating the flame retardant performance of a decorative fire retardant coating. Background Art

[0002] At present, there are two main methods for evaluating the flame retardant performance of decorative fire retardant coatings: the combustion test method and the oxygen index method.

[0003] The combustion test method is divided into the large plate combustion method and the small chamber combustion method; the large plate combustion method is to increase the temperature according to the requirements of the time-temperature standard curve under the specified substrate and specific combustion conditions, from the moment the specimen is exposed to fire to the time when the temperature of the back-fire surface of the specimen reaches 220°C or the back-fire surface of the specimen is penetrated by fire, this period of time is the flame retardant time, and the flame retardant performance of the coating is evaluated by the length of the flame retardant time. The longer the flame retardant time, the better the flame retardant performance of the coating. The small chamber combustion method is to test the fire retardant performance of the decorative fire retardant coating applied to the surface of the substrate under laboratory conditions, expressed by the combustion mass loss and carbonization volume. The mass loss refers to the difference in mass before and after the specimen is burned under the specified coating ratio and the specified combustion conditions; the carbonization volume refers to the product of the maximum length, maximum width and maximum depth of the carbonized substrate of the specimen under the specified coating ratio and the specified combustion conditions. The smaller the mass loss and the smaller the carbonization volume, the better the flame retardant performance of the coating.

[0004] The oxygen index method is to calculate the oxygen index of the coating by measuring the amount of oxygen consumed during the combustion process of the coating. The oxygen index refers to the minimum oxygen concentration required for the material to just maintain combustion in the oxygen-nitrogen mixed gas flow under the specified test conditions, expressed as a volume percentage. The higher the oxygen index, the more difficult the material is to burn and the better the flame retardant performance. Generally speaking, materials with an oxygen index greater than 26% are considered to have good flame retardant properties.

[0005] However, although the combustion test method can intuitively reflect the performance of the coating in an ideal fire scenario, the test parameters such as the standard temperature rise curve and fixed ventilation conditions are divorced from the actual complex and changeable fire environment. The test scenario is limited to laboratory setting conditions and does not fully consider the actual substrate combination and installation angle diversity. The oxygen index method measurement conditions are relatively idealized. The oxygen concentration changes dynamically in an actual fire, and the test is only carried out under a stable oxygen-nitrogen mixed gas flow, and the scenario is single, without involving factors such as thermal radiation and flame propagation direction.

[0006] In summary, the combustion test method and the oxygen index method have technical problems such as the test parameters being out of touch with reality and the test scenario being single. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a detection device for evaluating the flame retardant properties of decorative fire retardant coatings. Through this detection device, the technical problems of the current combustion test method and oxygen index method, such as the test parameters being out of touch with reality and the single test scenario, can be solved.

[0008] The above technical objectives of the present invention are achieved through the following technical solutions:

[0009] A detection device for evaluating the flame retardant performance of a decorative fire retardant coating, the detection device comprising a combustion test chamber and a sample fixture; a plurality of ventilation holes are provided on the top of the combustion test chamber, and electric shutters are arranged in the ventilation holes for controlling the ventilation area and ventilation direction to simulate different ventilation conditions.

[0010] Furthermore, multiple groups of heat radiation sources consisting of heating tubes are arranged around the inner wall of the combustion test chamber; the heating tubes are arranged in a matrix, and the power can be controlled individually or in groups to achieve heat radiation simulation of different areas and different intensities in the chamber.

[0011] Furthermore, a gas mixer is provided outside the combustion test chamber for inputting nitrogen-oxygen mixed gas into the combustion test chamber and adjusting the oxygen content in the nitrogen-oxygen mixed gas as required.

[0012] Furthermore, a laser smoke detector is arranged at the center of the top of the combustion test chamber; and a plurality of toxic gas sensors for detecting carbon monoxide, sulfur dioxide, or hydrogen cyanide are arranged at different heights in the combustion test chamber.

[0013] Furthermore, a gas sampling pump for extracting exhaust gas for secondary detection and analysis is provided outside the combustion test chamber, and a gas input end of the gas sampling pump is connected to the ventilation port.

[0014] Furthermore, a flue gas duct is provided on the gas output end or the gas input end of the gas sampling pump, and a flue gas comprehensive analysis unit for analyzing the flue gas pressure, oxygen concentration and carbon dioxide concentration in the flue gas duct is provided on the flue gas duct.

[0015] Furthermore, a light attenuation measuring unit for measuring the light flux in the smoke duct is arranged on the smoke duct.

[0016] Furthermore, a computer data acquisition and processing unit is provided outside the combustion test chamber for controlling the implementation process of the combustion test and receiving and processing the data collected by the flue gas comprehensive analysis unit and the light attenuation measurement unit.

[0017] Another object of the present invention is to provide a detection method for evaluating the flame retardant performance of a decorative fire retardant coating, which evaluates the flame retardant performance of the decorative fire retardant coating by using the aforementioned detection device, specifically, comprising the following steps:

[0018] (1) Preparation and installation of test specimens;

[0019] (2) Test procedure: Push the sample into the combustion chamber using a cart and control the combustion test parameters to conduct performance testing;

[0020] (3) Expression and evaluation of test results: A computer data acquisition and processing unit was used to evaluate the flame retardant-smoke suppression synergistic effect, flame retardant performance, and smoke generation characteristics of the decorative fire retardant coating.

[0021] In summary, the present invention has the following beneficial effects: the detection device in the present invention provides a combustion space close to the actual building environment. On the one hand, the state of the vents is adjusted by electric blinds to simulate different ventilation conditions, such as natural ventilation, mechanical ventilation or ventilation obstruction when a fire occurs, so that the coating can be tested under a variety of airflow environments. On the other hand, by setting a thermal radiation source to simulate the thermal radiation environment around the material in the fire, an uneven thermal radiation intensity distribution is set, similar to the complex conditions of the heat source at the real fire scene, to test the performance of the coating under different thermal radiation conditions. In addition, the gas mixer can dynamically adjust the oxygen concentration in the cabin according to the test requirements, which not only meets the conventional oxygen index test, but also simulates the changes in oxygen content during the fire process, and explores the flame retardant performance of the coating under the actual oxygen content fluctuation scenario. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of a detection device for evaluating the flame retardant performance of a decorative fire retardant coating in the present invention;

[0023] Figure 2 It is a schematic diagram of the internal structure of the combustion test chamber in the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, features and advantages of the present invention more obvious and understandable, the specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. The present invention can be implemented in many different forms and is not limited to the embodiments described herein.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0026] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0027] A detection device for evaluating the flame retardant performance of decorative fire retardant coatings is designed to comprehensively solve the technical problems existing in the existing evaluation methods for the flame retardant performance of decorative fire retardant coatings, simulate conditions closer to real fire scenes, and accurately evaluate the performance of fire retardant coatings in an all-round manner. The detection device has an overall rectangular structure and consists of several core parts, including a combustion test chamber, a thermal radiation and oxygen index control system, a smoke and toxic gas monitoring system, a sample fixture, and a data acquisition and analysis system. Each part works in coordination to achieve comprehensive testing. The details are as follows:

[0028] The main body of the combustion test cabin 1 is made of high temperature resistant and heat-insulating double-layer stainless steel plates, with internal dimensions of 5 meters in length, 4 meters in width and 3 meters in height, simulating the size of a general indoor building space. An opening 11 is provided on one side of the cabin body, and a fire door that can be opened and closed is provided on the opening 11, so as to facilitate the entry and exit of the sample. Sealing strips are provided around the door to ensure the sealing of the cabin during the test. Multiple vents are evenly distributed on the top (not shown in the accompanying drawings), and the vents are connected to electric shutters 3, which can accurately control the ventilation area and ventilation direction. The sample fixture 2 is installed on a trolley. The combustion test cabin 1 in the present invention provides a combustion space close to the actual building environment, and the state of the vents is adjusted by the electric shutters 3 to simulate different ventilation conditions, such as natural ventilation, mechanical ventilation or ventilation obstruction when a fire occurs, so that the coating is tested under a variety of airflow environments. The electric shutters 3 in the present invention are controlled by a computer data acquisition and processing unit 13, and the computer data acquisition and processing unit 13 is used to control the implementation process of the combustion test and receive and process the data collected by the smoke comprehensive analysis unit and the light attenuation measurement unit.

[0029] The inner wall of the combustion test chamber 1 is surrounded by a plurality of groups of heat radiation sources 4 composed of heating tubes, which are arranged in a matrix. The switches and power can be controlled individually or in groups to achieve heat radiation simulation of different areas and different intensities in the chamber. The oxygen index control is completed by connecting the gas mixer 5 of the chamber body. The gas mixer 5 is equipped with a high-precision gas flow sensor and a regulating valve, which can accurately mix the oxygen-nitrogen mixed gas and monitor the oxygen concentration in the chamber in real time. On the one hand, the heat radiation source 4 in the present invention can simulate the heat radiation environment around the material in the fire, set an uneven heat radiation intensity distribution, similar to the complex conditions of the heat source at the real fire scene, and test the performance of the coating under different heat radiation conditions; on the other hand, the gas mixer 5 in the present invention can dynamically adjust the oxygen concentration in the chamber according to the test requirements, which not only meets the conventional oxygen index test, but also simulates the changes in oxygen content during the fire process, and explores the flame retardant performance of the coating under the actual oxygen content fluctuation scene.

[0030] A laser smoke detector (not shown in the figure) is installed at the center of the top of the combustion test chamber 1 to ensure real-time monitoring of smoke concentration in every corner of the chamber. Multiple toxic gas sensors 6 are also installed at different heights in the chamber, such as carbon monoxide, sulfur dioxide, hydrogen cyanide, etc. Figure 2 As shown, the toxic gas sensors 6 from bottom to top are respectively a carbon monoxide sensor, a sulfur dioxide sensor, and a hydrogen cyanide sensor; the toxic gas sensor 6 is connected to the computer data acquisition and processing unit 13 outside the cabin through a data cable. In addition, a gas collecting hood is arranged above the vent, and the gas collecting hood is connected to the gas sampling pump 7 through the smoke duct 8, and the gas sampling pump 7 extracts the smoke in the combustion test cabin 1 for secondary detection and analysis. The laser smoke detector in the present invention accurately measures the smoke concentration generated during the combustion process, and combines the toxic gas sensor to feedback the generation of harmful gases in real time, and comprehensively reflects the characteristics of the combustion products of the coating. The gas sampling pump 7 collects exhaust gas analysis, which is used to evaluate the diffusion and dilution laws of smoke and toxic gases under ventilation conditions, and provides a basis for building fire prevention and smoke exhaust design and personnel evacuation safety.

[0031] The sample fixture 2 in the present invention is designed as a multifunctional modular structure. The main frame is made of high-strength aluminum alloy, which is lightweight and high temperature resistant. The sample fixture 2 includes an adjustable angle bracket with an angle adjustment range of 0°-90° to meet the testing requirements of different installation angles; the sample fixture 2 is also equipped with substrate slots of various materials and thicknesses to facilitate the replacement of different substrates, simulating the use scenarios of wood, steel, gypsum board, etc. combined with paint in actual buildings.

[0032] The flue gas comprehensive analysis unit in the present invention is composed of a pressure difference sensor and an oxygen / carbon dioxide concentration sensor. The flue gas comprehensive analysis unit is used to analyze the flue gas pressure, oxygen concentration and carbon dioxide concentration collected from the bidirectional probe 9 and the gas sampling probe 12 in the flue gas duct 8, and transmit the data electronically to the computer data processing unit 13. The specific structure can refer to the applicant's prior application document, whose publication number is CN114460134A.

[0033] The computer data processing unit 13 in the present invention mainly includes computer hardware and measurement and control software, which is used to control the implementation process of the combustion test and process the data collected by each sensor, calculate the volume flow rate, heat release rate HRR and smoke production rate SPR, and finally calculate the evaluation results through the measurement and control software: combustion growth rate index FI GRA0.2MJ / 0.4MJ, total heat release THR 600s in 600s, flame lateral spread length LFS, smoke generation rate index SMOGRA and total smoke generation TSP600s in 600s. The specific structure can refer to the applicant's prior application document, whose publication number is CN114460134A.

[0034] The smoke duct in the present invention is connected to the smoke hood to guide the smoke to the integrated measurement pipeline section where the bidirectional probe 9, thermocouple 10, light attenuation unit 11 and gas sampling probe 12 are placed. The specific structure can refer to the applicant's prior application document, which has a publication number of CN114460134A.

[0035] The bidirectional probe 9 in the present invention is used to collect the flue gas in the comprehensive measurement pipe section in the flue gas duct 8 and transport the flue gas to the comprehensive analysis unit for pressure analysis. The specific structure can refer to the applicant's prior application document, whose publication number is CN114460134A.

[0036] The thermocouple 10 in the present invention is used to measure the flue gas temperature of the comprehensive measuring pipe section in the flue gas duct 8, and transmit the data electrically to the computer data processing unit 13. The specific structure can refer to the applicant's prior application document, whose publication number is CN114460134A.

[0037] The light attenuation measuring unit 11 in the present invention calibrates the light source transmitting and receiving system through the filter, and is used to measure the light flux of the comprehensive measuring pipe section in the flue gas duct 8, and transmits the data electronically to the computer data processing unit 13. The specific structure can refer to the applicant's prior application document, whose publication number is CN114460134A.

[0038] The gas sampling probe in the present invention is used to collect the flue gas in the comprehensive measurement pipeline section in the flue gas duct 8, and transport the flue gas to the flue gas comprehensive analysis unit for oxygen concentration and carbon dioxide concentration analysis.

[0039] Another object of the present invention is to provide a detection method for evaluating the flame retardant performance of a decorative fire retardant coating, which evaluates the flame retardant performance of the decorative fire retardant coating by using the aforementioned detection device, specifically, comprising the following steps:

[0040] (1) Preparation and installation of test samples. The specific steps are as follows:

[0041] 1- According to the test requirements, select the decorative fire retardant coating to be tested, evenly apply it on the selected substrate, and prepare it into a standard size specimen. The coating thickness is set according to the product standard or actual application.

[0042] 2-Fix the sample on the sample fixture, use the angle adjustment function of the fixture to set the required installation angle, such as vertical, horizontal or inclined at a certain angle, and install the sample fixture with the sample on the trolley.

[0043] (2) Test procedure: Push the sample into the combustion chamber using a cart and control the combustion test parameters to conduct performance testing;

[0044] 1-Open the operation interface of the thermal radiation and oxygen index control system through the control terminal, set the initial thermal radiation intensity distribution in the cabin according to the test purpose, and choose uniform thermal radiation to simulate the early smoldering stage of fire, or set local high-intensity thermal radiation to simulate the direct impact area of ​​the flame; at the same time, set the initial oxygen index to determine the initial oxygen concentration in the cabin.

[0045] 2-In the smoke and toxic gas monitoring system software interface, calibrate the zero point of each sensor, set the data collection frequency of smoke concentration, toxic gas content, etc., to ensure accurate and timely data monitoring.

[0046] 3-Close the fire door of the combustion test chamber and ensure that it is well sealed. Then ignite one end of the sample through the remote ignition device. At the moment of ignition, the data acquisition and analysis system is started synchronously to start recording various data such as temperature, flame propagation, mass change, smoke and toxic gas generation.

[0047] 4- During the combustion process, the thermal radiation and oxygen index control system dynamically adjusts the thermal radiation intensity and oxygen concentration according to preset programs or manual intervention to simulate environmental changes during the development of the fire, such as the increase of thermal radiation as the flame spreads and the decrease of oxygen due to combustion consumption.

[0048] (3) Expression and evaluation of test results: A computer data acquisition and processing unit was used to evaluate the flame retardant-smoke suppression synergistic effect, flame retardant performance, and smoke generation characteristics of the decorative fire retardant coating.

[0049] 1- When the sample reaches the test termination conditions, such as the temperature of the sample's back-fire surface reaches the specified value, the flame is extinguished, or the preset burning time ends, stop ignition and data collection.

[0050] 2-The data collection and analysis system automatically processes the massive amounts of data collected and generates a flame retardant performance report for the coating based on a built-in standard algorithm. The report includes the flame retardant-smoke suppression synergistic effect, flame retardant performance, and smoke production characteristics of the decorative fire retardant coating. The built-in standard algorithm can refer to the applicant's prior application documents (paragraphs 0077-0079 of its specification), and its publication number is CN114460134A.

[0051] 3-The report can also include key indicators such as the peak heat release rate, average heat release rate, total heat release, flame retardant time, smoke density peak, toxic gas release, etc. of the decorative fire retardant coating, and compare it with the data of similar products in the database to intuitively present the advantages and disadvantages of the flame retardant performance of the coating.

[0052] In summary, the present invention improves the structure of the existing detection device so that when the detection device tests the flame retardant properties of decorative fire retardant coatings, it can comprehensively and truly reflect the performance of the coatings in complex actual fire scenes, thereby providing solid and reliable technical support for the research and development, quality inspection and engineering application of fire retardant coatings.

[0053] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A detection device for evaluating the flame retardant performance of a decorative fire retardant coating, characterized in that: The detection device comprises a combustion test chamber and a sample fixture; a plurality of ventilation holes are provided on the top of the combustion test chamber, and electric shutters are arranged in the ventilation holes for controlling the ventilation area and ventilation direction to simulate different ventilation conditions.

2. The detection device according to claim 1, characterized in that: Multiple groups of heat radiation sources consisting of heating tubes are arranged around the inner wall of the combustion test chamber; the heating tubes are arranged in a matrix, and the power can be controlled individually or in groups to achieve heat radiation simulation of different areas and intensities in the chamber.

3. The detection device according to claim 1, characterized in that: A gas mixer is arranged outside the combustion test chamber to input nitrogen-oxygen mixed gas into the combustion test chamber and adjust the oxygen content in the nitrogen-oxygen mixed gas as needed.

4. The detection device according to claim 1, characterized in that: A laser smoke detector is arranged at the center of the top of the combustion test chamber; a plurality of toxic gas sensors for detecting carbon monoxide, sulfur dioxide, or hydrogen cyanide are arranged at different heights in the combustion test chamber.

5. The detection device according to claim 1, characterized in that: A gas sampling pump for extracting exhaust gas for secondary detection and analysis is arranged outside the combustion test chamber, and a gas input end of the gas sampling pump is connected to the ventilation port.

6. The detection device according to claim 5, characterized in that: A flue gas duct is arranged on the gas output end or the gas input end of the gas sampling pump, and a flue gas comprehensive analysis unit for analyzing the flue gas pressure, oxygen concentration and carbon dioxide concentration in the flue gas duct is arranged on the flue gas duct.

7. The detection device according to claim 6, characterized in that: A light attenuation measuring unit for measuring the light flux in the flue gas duct is arranged on the flue gas duct.

8. The detection device according to claim 7, characterized in that: A computer data acquisition and processing unit is arranged outside the combustion test chamber for controlling the implementation process of the combustion test and receiving and processing the data collected by the flue gas comprehensive analysis unit and the light attenuation measurement unit.

9. A detection method for evaluating the flame retardant performance of a decorative fire retardant coating, characterized in that: The flame retardant properties of the decorative fire retardant coating are evaluated using the detection device described in any one of claims 1 to 8.

10. The detection method according to claim 9, characterized in that: The following steps are involved: (1) Preparation and installation of test specimens; (2) Test procedure: Push the sample into the combustion chamber using a cart and control the combustion test parameters to conduct performance testing; (3) Expression and evaluation of test results: A computer data acquisition and processing unit was used to evaluate the flame retardant-smoke suppression synergistic effect, flame retardant performance, and smoke generation characteristics of the decorative fire retardant coating.

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