Rapid heating fire resistance test device

Abstract

The invention discloses a rapid heating fire resistance test device, which relates to the technical field of fire resistance test of fireproof materials, and comprises a pressure transmitter, a thermocouple, a control cabinet, a natural gas header pipe, an air blower, an air header pipe, a burner, a flame detector, an igniter, a detection electrode and an ignition electrode, the natural gas header pipe is further provided with a pressure regulating valve located on the outlet side of the filter and an air-fuel proportional valve located on the outlet side of the pressure regulating valve. An air inlet of the air-fuel proportional valve communicates with the air header pipe. The ignition electrode extends into a combustion area of the burner; the flame detector is an ion flame detector; a smoke cooling device is arranged on the smoke exhaust pipeline between the exhaust fan and the test furnace; the control cabinet is electrically connected with the blower through the frequency converter. The ignition success rate can be increased, natural gas and combustion air are proportionally adjusted through the air-fuel proportional valve, and automatic and accurate control over the furnace temperature is easy to achieve; a natural gas path is high in stability; mistaken monitoring of flames can be avoided; and the service life of the exhaust fan can be prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of fire resistance performance testing of fireproof materials, in particular to a rapid temperature rise fire resistance testing device. Background Art

[0002] Rapid temperature rise fire resistance test equipment is used to inspect and evaluate the fire resistance performance of fire protection materials used in petrochemical bases, offshore or marine buildings (structures), oil and gas fields or oil storage tank areas, and tunnels. The products tested include: steel structure fire retardant coatings, fire protection panels, concrete structure fire retardant coatings, inorganic fibers, etc. Its main technical content is fire resistance performance testing. Existing rapid temperature rise fire resistance test equipment has the following defects:

[0003] 1) Air and natural gas cannot be adjusted automatically. The natural gas flow is adjusted by an electric regulating valve, while the combustion air is adjusted manually. This adjustment method is difficult to achieve the optimal air-fuel ratio, and it is not easy to achieve automatic control of the furnace temperature.

[0004] 2) The liquefied natural gas filling pressure is unstable and there is a lack of a pressure stabilizing device;

[0005] 3) The burner assembly uses an ignition gun to ignite the natural gas ejected from the burner. However, the flame of the ignition gun is floating and has no rigidity. Once the furnace pressure fluctuates or the air flow blows, the flame of the ignition gun will go out, posing a hidden danger to the safety of the furnace.

[0006] 4) The test furnace is a circular furnace, and a one-to-one photoelectric flame detector is set for the burner. The photosensitive tube can not only sense its own flame, but also monitor the flame of another burner. The flame detector is prone to misdetection.

[0007] 5) The temperature inside the rapid heating refractory test furnace can reach up to 1200℃, and the constant temperature time is long. Ordinary fans usually make a clamor after more than ten minutes, causing great safety hazards.

[0008] 6) Rapid heating fire resistance test equipment requires fast heating speed and high temperature. The heat load is large during heating and small during insulation. Therefore, the dynamic range of heat load is required to be large. In the past, furnace temperature control was mainly through electric regulating valves, and there was no proportional supply of air, which made it difficult for the furnace temperature to operate according to the curve. Summary of the Invention

[0009] The present invention provides a rapid temperature rise fire resistance testing device, which can solve the above problems.

[0010] In order to solve the above problems, the technical solutions adopted by the present invention are as follows:

[0011] The present invention provides a rapid temperature rise fire resistance test device, comprising a pressure transmitter, a thermocouple, a control cabinet, a natural gas main, a hand valve, a filter and a pressure gauge arranged on the natural gas main, a blower, an air main connected to the outlet end of the blower, a burner assembly installed on a test furnace, and an exhaust fan connected to the test furnace through a smoke exhaust pipe, wherein the burner assembly comprises a burner, a flame detector, an igniter, a detection electrode and an ignition electrode, the natural gas main is further provided with a pressure regulating valve located on the outlet side of the filter and an air-fuel ratio valve located on the outlet side of the pressure regulating valve, the air inlet of the air-fuel ratio valve is connected to the air main; the ignition electrode extends into the combustion area of ​​the burner; the flame detector is an ion flame detector; a smoke cooling device is provided in the smoke exhaust pipe between the exhaust fan and the test furnace; the control cabinet is electrically connected to the blower through a first frequency converter.

[0012] As a further description of the above technical solution, the pressure gauge includes a first pressure gauge and a second pressure gauge, and the hand valve includes a first hand valve, a second hand valve, a third hand valve, a fourth hand valve and a fifth hand valve; the first hand valve, the filter, the first pressure gauge, the second hand valve, the pressure regulating valve, the second pressure gauge, the air-fuel ratio valve and the fourth hand valve are installed step by step on the natural gas main; one end of the third hand valve is connected between the pressure regulating valve and the second hand valve, and the other end is connected to the outlet side of the fourth hand valve and one end of the fifth hand valve; the other end of the fifth hand valve is connected between the second pressure gauge and the air-fuel ratio valve.

[0013] As a further description of the above technical solution, the burner assembly includes a sixth hand valve, a solenoid valve, a manual butterfly valve, as well as the burner, flame detector, igniter, detection electrode and ignition electrode; the sixth hand valve, solenoid valve and the natural gas inlet of the burner are connected step by step; the air inlet of the burner is connected to the air main through the manual butterfly valve; the detection electrode is located in the combustion area of ​​the burner; the flame detector is electrically connected to the detection electrode; the igniter is electrically connected to the ignition electrode; the flame detector, igniter and solenoid valve are electrically connected to the control cabinet.

[0014] As a further description of the above technical solution, the natural gas main is provided with a gas leakage monitoring device; an explosion-proof pressure relief device is provided on the top of the test furnace; the flue gas cooling device is a circulating water cooling device; the air main is provided with a pressure sensor; and the control cabinet is electrically connected to the pressure sensor and the gas alarm system.

[0015] As a further description of the above technical solution, the control cabinet is electrically connected to the exhaust fan through a second inverter.

[0016] As a further description of the above technical solution, the control cabinet is electrically connected to the host computer.

[0017] As a further description of the above technical solution, there are six burner assemblies, four of which are evenly arranged in a circumferential direction in the upper part of the furnace of the test furnace, and two are arranged near the bottom.

[0018] As a further description of the above technical solution, there are two pressure transmitters for measuring the pressure at different positions in the test furnace; there are eight thermocouples for measuring the temperature at different positions in the test furnace.

[0019] As a further description of the above technical solution, when the device is debugging the tunnel RABT fire curve, the following settings are made during the cooling process: when the average temperature in the test furnace is 15°C higher than the current standard temperature, each burner is closed in turn; when the average temperature in the test furnace is 15°C lower than the current standard temperature, each burner is opened in turn, and the blower frequency is synchronized with the exhaust fan; when the average temperature in the test furnace drops to 390°C and all burners are in the closed state, the blower and exhaust fan are both running at full load; among them, the current standard temperature refers to the temperature requirement determined according to the current stage of the tunnel RABT fire curve in the tunnel fire scenario.

[0020] As a further description of the above technical solution, when debugging the power fire curve, tunnel HC fire curve and petrochemical fire curve, four burners were selected for testing, and the exhaust fan was operated at full load in the constant temperature stage.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) The ignition gun is removed, and the burner is ignited directly, which improves the ignition success rate, simplifies the system, and makes it easier to control the furnace temperature. The ratio of natural gas and combustion air is adjusted by the air-fuel ratio valve, which makes it easier to achieve the optimal air-fuel ratio and facilitates automatic and precise control of the furnace temperature. A pressure regulating valve is installed on the natural gas main pipeline to make the natural gas pressure entering the device more stable. The photoelectric flame detector is replaced with an ion flame detector to avoid false flame monitoring. A flue gas cooling device is added to increase the service life of the exhaust fan. The blower frequency is adjusted by the frequency converter to accurately control the air supply volume. The air-fuel ratio is accurately controlled by the air-fuel ratio valve to meet the temperature control requirements, so that the furnace temperature can operate according to the curve.

[0023] 2) In the past, when debugging the RABT fire curve in a tunnel, the cooling process required the furnace temperature to drop from 1200°C to 20°C within 110 minutes. For a furnace that had already been red-hot, it was extremely difficult to lower the temperature according to the curve within 110 minutes. The present invention improves the operating method, making it easier for the area deviation of the temperature curve in the furnace to meet the requirements of the test method XF / T 714-2007 (standard number for "Rapid Heating Fire Resistance Test Method for Fire Protection Materials for Components"), thereby reducing the operating difficulty.

[0024] 3) Previously, the power fire curve, tunnel HC fire curve, and petrochemical fire curve encountered the same problem during debugging: after the furnace temperature reached the highest temperature of the curve, the temperature inside the test furnace continued to rise at the lowest power. When conducting these tests, the present invention selects four burners for testing, and the exhaust fan runs at full load during the constant temperature stage, so that the constant temperature process after the furnace temperature reaches the highest temperature of the curve is stable and reliable.

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, embodiments of the present invention are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 is a schematic diagram of the rapid heating fire resistance test device described in the embodiment;

[0028] Figure 2 is a schematic diagram of the natural gas main system in the embodiment;

[0029] Figure 3 is a schematic diagram of the burner assembly in the embodiment;

[0030] In the figure: 1. Natural gas main system; 2. Burner assembly; 3. Test furnace; 4. Pressure transmitter; 5. Thermocouple; 6. Gas leak monitoring device; 7. Blower; 8. Pressure sensor; 9. First inverter; 10. Control cabinet; 11. Host computer; 12. Second inverter; 13. Flue gas cooling device; 14. Exhaust fan; 15. Explosion-proof pressure relief device; 16. Gas alarm system; 17. Air main; 18. Filter; 19. First pressure gauge; 20. Pressure regulating valve; 21. Second pressure gauge; 22. Air-fuel ratio valve; 23. First manual valve; 24. Second manual valve; 25. Third manual valve; 26. Fourth manual valve; 27. Fifth manual valve; 28. Natural gas main; 29. ​​Solenoid valve; 30. Manual butterfly valve; 31. Burner; 32. Detection electrode; 33. Ignition electrode; 34. Flame detector; 35. Ignitor; 36. Sixth manual valve. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0032] Please refer to Figure 1 、 Figure 2 and Figure 3 The present embodiment provides a rapid temperature rise fire resistance test device, including a pressure transmitter 4, a thermocouple 5, a host computer 11, a control cabinet 10 electrically connected to the host computer 11, a natural gas main pipe 28, a hand valve, a filter 18 and a pressure gauge provided on the natural gas main pipe 28, a blower 7, an air main pipe 17 connected to the outlet end of the blower 7, a burner assembly installed in the test furnace 3, an exhaust fan 14 connected to the test furnace 3 through a smoke exhaust pipe, and the burner assembly includes a burner 31, a flame detector 34, an igniter 35, a detection electrode 32 and a point The fire electrode 33 and the natural gas main 28 are also provided with a pressure regulating valve 20 located on the outlet side of the filter 18 and an air-fuel ratio valve 22 located on the outlet side of the pressure regulating valve 20. The air inlet of the air-fuel ratio valve 22 is connected to the air main 17. The ignition electrode 33 extends into the combustion area of ​​the burner 31. The flame detector 34 is an ion flame detector. A flue gas cooling device 13 is provided in the exhaust pipe between the exhaust fan 14 and the test furnace 3. The control cabinet 10 is electrically connected to the blower 7 through the first inverter 9 and is electrically connected to the exhaust fan 14 through the second inverter 12.

[0033] In this embodiment, the pressure gauges include a first pressure gauge 19 and a second pressure gauge 21, and the hand valves include a first hand valve 23, a second hand valve 24, a third hand valve 25, a fourth hand valve 26, and a fifth hand valve 27; the first hand valve 23, the filter 18, the first pressure gauge 19, the second hand valve 24, the pressure regulating valve 20, the second pressure gauge 21, the air-fuel ratio valve 22, and the fourth hand valve 26 are installed step by step on the natural gas main 28; one end of the third hand valve 25 is connected between the pressure regulating valve 20 and the second hand valve 24, and the other end is connected to the outlet side of the fourth hand valve 26 and one end of the fifth hand valve 27; the other end of the fifth hand valve 27 is connected between the second pressure gauge 21 and the air-fuel ratio valve 22.

[0034] In this embodiment, the burner assembly includes a sixth hand valve 36, a solenoid valve 29, a manual butterfly valve 30, as well as a burner 31, a flame detector 34, an igniter 35, a detection electrode 32 and an ignition electrode 33; the sixth hand valve 36, the solenoid valve 29 and the natural gas inlet of the burner 31 are connected step by step; the air inlet of the burner 31 is connected to the air main 17 through the manual butterfly valve 30; the detection electrode 32 is located in the combustion area of ​​the burner 31; the flame detector 34 is electrically connected to the detection electrode 32; the igniter 35 is electrically connected to the ignition electrode 33; the flame detector 34, the igniter 35 and the solenoid valve 29 are electrically connected to the control cabinet 10.

[0035] In this embodiment, a gas leakage monitoring device 6 is provided on the natural gas main 28; an explosion-proof pressure relief device 15 is provided on the top of the test furnace 3; the flue gas cooling device 13 is a circulating water cooling device; a pressure sensor 8 is provided on the air main 17; and the control cabinet 10 is electrically connected to the pressure sensor 8 and the gas alarm system 16.

[0036] In this embodiment, the test furnace 3 has a size of Φ1800×3000mm, a furnace size of Φ1300×1800mm, and a furnace clearance of 2.39m 3 The test furnace 3 is equipped with 6 burner assemblies, 4 of which are evenly arranged in the circumference in the upper part of the furnace (a plane 2.18m above the bottom surface), and 2 are arranged near the bottom (a plane 1m above the bottom surface). The natural gas consumption of burner 31 is 50m 3 / h.

[0037] The valve sizes of the manual valve and the pressure regulating valve 20 are both DN50, the pipeline size of the filter 18 is DN50, the valve size of the air-fuel ratio valve 22 is DN80, the valve size of the solenoid valve 29 is DN32, and the diameter of the natural gas pipe in front of each burner 31 equipped with the solenoid valve 29 is DN32; the natural gas pressure in front of the pressure regulating valve 20 is 0.2MPa, and after pressure regulation by the pressure regulating valve 20, the pressure becomes 15-20kPa.

[0038] The technical parameters of blower 7 are: power 5.5kW, full pressure 3407Pa, flow rate 3251m 3 / h, controlled by a matching 5.5kW first frequency converter 9. The diameter of the air duct before each burner 31 is DN80.

[0039] The technical parameters of exhaust fan 14 are: power 7.5kW, full pressure 5323Pa, flow rate 3166m 3 / h, controlled by a matching 7.5kW second frequency converter 12. The exhaust duct has a diameter of DN125. The pipe between the exhaust port of test furnace 3 and exhaust fan 14 is covered with a DN300 casing, which is part of the circulating water cooling device. Cooling water enters the casing from the top and exits from the bottom. The casing is 6m long. The exhaust duct of exhaust fan 14 is connected to the flue gas treatment device of the quality inspection center.

[0040] There are two pressure transmitters 4 for measuring the pressure at different positions in the test furnace 3 ; there are eight thermocouples 5 for measuring the temperature at different positions in the test furnace 3 .

[0041] All test data were collected by a data acquisition box. The rapid heating fire resistance test device collected 8 furnace temperature signals (obtained through the eight thermocouples 5 mentioned above), 18 sample temperature signals (obtained through thermoelectric sensors installed on the samples), and 2 furnace pressure signals (obtained through pressure transmitters 4).

[0042] Host computer 11 processes data, displays it, and issues control commands. After the test, host computer 11 prints out test information, furnace temperature curves and data, furnace pressure, and specimen temperature curves and data. Furnace control cabinet 10 handles on-site commissioning, maintenance, and inspection of test furnace 3. It receives commands from host computer 11 to control the gas and air supply systems and displays the operating status, temperature, and pressure of test furnace 3. The furnace temperature control principle of the rapid temperature rise refractory test device is to control the air supply volume by adjusting the frequency of blower 7 via first inverter 9, and the air-fuel ratio valve 22 to control the air-fuel ratio to achieve the required temperature control.

[0043] In this embodiment, flame monitoring is to monitor the combustion state of the burner 31 through an ion flame detector. If the burner 31 fails to ignite once, a second ignition will be performed. If the second ignition fails, the natural gas solenoid valve 29 of the burner 31 will automatically close. In addition, this embodiment adopts the furnace pressure over-limit shutdown method, that is, when the pressure in the furnace exceeds a certain limit, the test furnace 3 will automatically shut down the blower 7 and all natural gas solenoid valves 29, and the test furnace 3 will stop working; explosion-proof pressure relief is only when the explosion in the furnace cannot be avoided, the explosion-proof hole on the top of the furnace is lifted up, the furnace pressure drops, and the safety of the test furnace 3 and on-site staff is ensured; gas leakage monitoring is only effective when the gas pipeline of the test furnace 3 leaks. At this time, the gas alarm system 16 installed in the combustion test hall where this device is located will alarm to remind the staff to suspend the test, close the outdoor gas supply main, and turn on all explosion-proof axial flow fans on the roof. At the same time, indoor personnel are evacuated in time.

[0044] When debugging the tunnel RABT fire curve, the rapid temperature rise fire resistance test device described in this embodiment is set as follows during the cooling process: when the average temperature in the test furnace 3 is 15°C higher than the current standard temperature, each burner 31 is closed in turn; when the average temperature in the test furnace 3 is 15°C lower than the current standard temperature, each burner 31 is opened in turn, and the frequency of the blower 7 is synchronized with the exhaust fan 14; when the average temperature in the test furnace 3 drops to 390°C and all the burners 31 are in the closed state, the blower 7 and the exhaust fan 14 are both running at full load; wherein, the current standard temperature refers to the temperature requirement determined according to the current stage of the tunnel RABT fire curve in the tunnel fire scenario.

[0045] When debugging the electric power fire curve, tunnel HC fire curve, and petrochemical fire curve, the rapid temperature rise fire resistance test device of this embodiment uses four burners 31 for testing, and the exhaust fan 14 runs at full load in the constant temperature stage.

[0046] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A rapid temperature rise fire resistance test device, comprising a pressure transmitter (4), a thermocouple (5), a control cabinet (10), a natural gas main (28), a hand valve, a filter (18) and a pressure gauge arranged on the natural gas main (28), a blower (7), an air main (17) connected to the outlet end of the blower (7), a burner assembly installed in a test furnace (3), and connected to the exhaust fan (14) of the test furnace (3) through a smoke exhaust duct, wherein the burner assembly comprises a burner (31), a flame detector (34), an igniter (35), a detection electrode (32) and an ignition electrode (33), characterized in that: The natural gas main pipe (28) is further provided with a pressure regulating valve (20) located on the outlet side of the filter (18) and an air-fuel ratio valve (22) located on the outlet side of the pressure regulating valve (20), and the air inlet of the air-fuel ratio valve (22) is connected to the air main pipe (17); the ignition electrode (33) extends into the combustion area of ​​the burner (31); the flame detector (34) is an ion flame detector; the exhaust pipe between the exhaust fan (14) and the test furnace (3) is provided with a flue gas cooling device (13); the control cabinet (10) is electrically connected to the blower (7) through a first frequency converter (9).

2. The rapid temperature rise fire resistance test device according to claim 1, characterized in that: The pressure gauge includes a first pressure gauge (19) and a second pressure gauge (21); the hand valve includes a first hand valve (23), a second hand valve (24), a third hand valve (25), a fourth hand valve (26) and a fifth hand valve (27); the first hand valve (23), the filter (18), the first pressure gauge (19), the second hand valve (24), the pressure regulating valve (20), the second pressure gauge (21), the air-fuel ratio valve (22) and the fourth hand valve (26) are installed step by step on the natural gas main pipe (28); one end of the third hand valve (25) is connected between the pressure regulating valve (20) and the second hand valve (24), and the other end is connected to the outlet side of the fourth hand valve (26) and one end of the fifth hand valve (27); the other end of the fifth hand valve (27) is connected between the second pressure gauge (21) and the air-fuel ratio valve (22).

3. The rapid temperature rise fire resistance test device according to claim 1, characterized in that: The burner assembly comprises a sixth manual valve (36), a solenoid valve (29), a manual butterfly valve (30), the burner (31), a flame detector (34), an igniter (35), a detection electrode (32) and an ignition electrode (33); the sixth manual valve (36), the solenoid valve (29) and the natural gas inlet of the burner (31) are connected step by step; the air inlet of the burner (31) is connected to the air main pipe (17) through the manual butterfly valve (30); the detection electrode (32) is located in the combustion area of ​​the burner (31); the flame detector (34) is electrically connected to the detection electrode (32); the igniter (35) is electrically connected to the ignition electrode (33); the flame detector (34), the igniter (35) and the solenoid valve (29) are electrically connected to the control cabinet (10).

4. The rapid temperature rise fire resistance test device according to claim 1, characterized in that: The natural gas main pipe (28) is provided with a gas leakage monitoring device (6); the top of the test furnace (3) is provided with an explosion-proof pressure relief device (15); the flue gas cooling device (13) is a circulating water cooling device; the air main pipe (17) is provided with a pressure sensor (8); the control cabinet (10) is electrically connected to the pressure sensor (8) and the gas alarm system (16).

5. The rapid temperature rise fire resistance test device according to claim 1, characterized in that: The control cabinet (10) is electrically connected to the exhaust fan (14) via a second frequency converter (12).

6. The rapid temperature rise fire resistance test device according to claim 1, characterized in that: The control cabinet (10) is electrically connected to a host computer (11).

7. The rapid temperature rise fire resistance test device according to claim 1, characterized in that: There are six burner assemblies, four of which are evenly arranged in a circumferential direction in the upper part of the furnace of the test furnace (3), and two are arranged near the bottom.

8. The rapid temperature rise fire resistance test device according to claim 7, characterized in that: There are two pressure transmitters (4) for measuring the pressure at different positions in the test furnace (3); there are eight thermocouples (5) for measuring the temperature at different positions in the test furnace (3).

9. The rapid temperature rise fire resistance test device according to claim 8, characterized in that: When the device is debugging the tunnel RABT fire curve, the following settings are performed during the cooling process: when the average temperature in the test furnace (3) is higher than the current standard temperature by 15°C, each burner (31) is closed in sequence; when the average temperature in the test furnace (3) is lower than the current standard temperature by 15°C, each burner (31) is opened in sequence, and at the same time, the frequency of the blower (7) is synchronized with the exhaust fan (14); when the average temperature in the test furnace (3) drops to 390°C and all the burners (31) are in the closed state, the blower (7) and the exhaust fan (14) are both operated at full load; wherein, the current standard temperature refers to the temperature requirement determined according to the current stage of the tunnel RABT fire curve in the tunnel fire scene.

10. The rapid temperature rise fire resistance test device according to claim 8, characterized in that: When the device is used to debug the electric power fire curve, the tunnel HC fire curve and the petrochemical fire curve, four burners (31) are selected for testing, and the exhaust fan (14) is operated at full load in the constant temperature stage.

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