KR20020044388A - back fire safety system - Google Patents

Abstract

PURPOSE: A backfire preventing system installed on a gas inlet pipe of an annealing furnace is provided which is installed on a gas supply pipe for combustion in the annealing furnace to prevent facility accidents due to backfire at the combustion part or abnormal pressure generation of inlet gas. CONSTITUTION: The backfire preventing system installed on a gas inlet pipe of an annealing furnace comprises an external body(100) which is equipped with a gas inlet(20) and a gas outlet(40) connected to the gas inlet pipe(5), into the center of which a fixing shaft(1) is vertically penetrated, and at the upper part of which is sealed by a cover part; a cylindrical member(8) which is installed at the lower part of the cover part around the fixing shaft(1) and has a plurality of through holes(9); an internal body part(10) which is installed under the lower end part of the cylindrical member(8) inward the external body(100), and in which through holes are installed; first and second sealing members(22,42) physically connecting and fixing the external body(100) to the internal body part(10) and separately forming a gas inlet passage(21) and a gas outlet passage(41) in a space between the external body(100) and the internal body part(10); a cylinder(3) lifting the fixing shaft(1) upward by signals of a control part(70); first and second opening and closing disks(16,26) the center of which are connected to the fixing shaft(1), and open or close the upper through holes of the internal body part(10) from the upper and lower sides respectively; a filter member(19) the center of which is connected to the lower part of the fixing shaft(1) by a nut(25), and which is installed on the lower inner wall of the internal body part(10) to cover the lower through holes of the internal body part(10); a first elastic member(33) installed between the cover part and the first opening and closing disk(16) around the fixing shaft(1), and a second elastic member(44) installed between the second opening and closing disk(26) and the filter member(19) around the fixing shaft(1); and a backfire sensing sensor(30) installed on the gas outlet passage(41) to generate control signals by sensing backfire of a burner.

Description

Backfire safety system installed in gas inlet pipe of annealing furnace {back fire safety system}

The present invention relates to a flashback prevention device installed in the gas inlet pipe of the annealing furnace, and more particularly, installed in the supply pipe for the gas for combustion in the annealing furnace equipment due to backfire in the combustion unit or abnormal pressure of the inlet gas The present invention relates to a flashback prevention device installed in a gas inlet pipe of an annealing furnace to prevent an accident.

In general, annealing furnaces installed in steel making facilities are core equipments for determining the material of metals by heat-treating cold-rolled steel sheets as radiant heat, and these annealing furnaces recrystallize and grow into a rolling structure by heating steel. It removes stress and makes tissue with proper toughness. That is, the annealing furnace is to maintain the heating time of the steel in accordance with a predetermined temperature according to the carbon component and the additive element in order to remove the softening of the internal stress of the steel, and then to cool it to produce a material of the metal desired by the demand .

This annealing furnace is composed of a plurality of burners to work according to the required heat amount of each zone, each burner receives the gas required for combustion from the supply gas pipe.

On the other hand, the supply gas piping is generally equipped with a backfire prevention device that can buffer the pressure backing due to the flame or micro-explosion due to abnormality in the supply pressure of the supply gas or backfire in the combustion section. .

Such a conventional flashback prevention device is illustrated in FIGS. 1 and 2. Referring to the drawing, a conventional flashback prevention apparatus is described as follows.

1, the branch pipe 104 is formed in the gas inlet pipe part 105, and the upper flange 106 and the lower flange 107 are formed at the upper end thereof, and the copper plate 101 is inserted therebetween to seal it. When the copper plate 101 is pushed upward by the pressure at the time of backfire, it contacts the pin 103 protruding in the center of the flange fixing part 102 and the copper plate 101 is blown to protect other equipment by backfire. That's the way. This weakly formed any one of the pipes in a way to control the excessive pressure generated when the backfire occurs, there is a disadvantage that can not be adjusted at all when the occurrence of abnormal pressure, hunting, pressure drop when the gas is introduced. In addition, if the copper plate 101 is broken once, there is a problem that the copper plate 101 must be replaced after stopping the operation of the facility.

In the case of Figure 2 covers the fixed plate 117 on the branch pipe 114 of the gas inlet pipe 115 and press the fixed plate 117 by using the tension of the spring 110 inserted about the fixed shaft 114. When the fine hunting of the abnormal pressure occurs, the buffer of the fixed plate is buffered to some extent, and when the backfire occurs, the gas is discharged to the discharge port 118 by the lifting of the fixed plate 117 by the reverse of the excessive pressure. When the lowering again pushes the fixing plate 117 downward with the tension of the spring 115 and the pressure for pressing the fixing plate 117 is adjusted by the spring tension adjustment handle 116. In this case, however, the pressure is not adjusted at all except the pressure once adjusted by the handle 116, and when it is fixed and installed for a long time, the spring 115 may be rusted and may not operate. ), There is a risk of breakage and the rust is generated in close contact with the narrow discharge port 118 and the fixed plate 117 is not the situation to properly function as a flashback prevention device.

Therefore, the present invention is based on the problems of the conventional flashback prevention device as described above, and an object of the present invention is to filter out impurities such as tar and foreign substances, etc., from the components of the gas introduced into the annealing furnace. In case of pressure hunting, a filter is built inside the flashback prevention device to completely buffer the internal flashback prevention device. In case of a flashback, the impact pressure is first blocked from the filter. Its main purpose is to provide a flashback prevention device that automatically shuts off the system, thereby minimizing the damage of the facility in case of flashback and preventing the downtime of the facility.

1 is a schematic diagram of a conventional flashback prevention device

2 is a schematic view of another conventional flashback prevention device

3 is a cross-sectional view of the flashback prevention device according to the present invention

4 is a partial cutaway perspective view of FIG.

5 is a view showing a flame sensor.

* Description of the main parts of the drawing *

1: Fixed shaft 3: Cylinder

4: cover part 8: cylindrical member

10: inner body 16, 26: sealed disk

33, 44: elastic member 22: flame detection sensor

In order to achieve the above object, the flashback prevention apparatus of the present invention has an inlet and an outlet of a gas connected to a gas inlet pipe, and has an outer body part perpendicularly penetrated to the center and sealed by a cover part at the top; A cylindrical member installed below the cover part around the fixed shaft and having a plurality of holes; An inner body portion having a through hole vertically installed on a lower side of the lower end of the cylindrical member inwardly of the outer body portion and having a through hole; A first sealing member and a second sealing member physically fixed to the outer body portion and the inner body portion, and separately forming a gas inflow passage and a gas outlet passage in a space between the outer body portion and the inner body portion; A cylinder for lifting the fixed shaft upward by a signal from the controller; A first opening / closing disk and a second opening / closing disk which are fixedly connected to the fixed shaft at a center thereof and open and close the upper through-holes of the inner body part from above and below, respectively; A filter member fixedly connected to the lower part of the fixed shaft at the center by a nut and covering the lower through-hole of the inner body part from the lower inner wall of the inner body part; A second elastic member installed between the cover part and the first opening / closing disk with a first elastic member installed about the fixed shaft and the second opening / closing disk with a filter member; And a backfire detection sensor installed on the gas outflow passage and detecting a backfire of the burner to generate a control signal.

Hereinafter, a flashback prevention apparatus of the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view of a flashback prevention apparatus according to the present invention, Figure 4 is a partial cutaway perspective view and Figure 5 is a view showing a flame sensor.

Referring to Figures 3 and 4, the flashback prevention apparatus of the present invention is installed in the gas inlet pipe (5) of the annealing furnace, reference numeral 20 is an inlet of the gas connected to the gas inlet pipe (5) and 40 Is a discharge port of the gas connected to the gas inlet pipe 5 on the outlet side of the combustion unit (not shown). Reference numeral 1 denotes a fixed shaft and vertically penetrates the center of the body portion, and 4 denotes a cover portion to seal the outer body portion 100. 8 is a cylindrical member having a plurality of through holes (9) is installed at the lower end of the cover portion (4) around the fixed shaft (1) and the gas is introduced through the through holes (9). 10 is an inner body portion, which is installed around the fixed shaft 1 below the lower end of the cylindrical member 8 inwardly of the outer body portion 100 and has a through hole up and down. The first opening and closing disk 16 and the second opening and closing disk 26 for opening and closing the through hole are provided above and below the upper through hole of the inner body part 10. The two-open disk 26 is fixedly connected at the center and the fixed shaft (1).

Reference numeral 13 is an elastic member contact plate coupled by the nut member 14 between the lower portion of the first elastic member 33 and the upper portion of the first opening / closing disk 16 to closely adhere the first elastic member 33. It plays a role.

Reference numerals 22 and 42 denote the first sealing member and the second sealing member, respectively, to physically connect the outer body part 100 and the inner body part 10 to each other, and to fix the outer body part 100 and the inner body part 10. The gas inflow passage 21 and the gas outflow passage 41 are separately formed in the space between them. 3 serves to lift the fixed shaft 1 upward by a signal from the control unit 70 as a cylinder, and 19 is fixed by nuts 18 and 25 at the bottom of the fixed shaft 1 at the center as a filter member. Connected to the inner wall of the lower through hole of the inner body part 10 and covering the lower through hole of the inner body part 10. The filter member 19 is coupled by nut members 18 and 25 to enable disassembly and cleaning or replacement in long term use.

Reference numerals 33 and 44 denote first elastic members and second elastic members, respectively, and the first elastic members 33 are installed around the fixed shaft 1 between the cover part 4 and the first opening / closing disk 16. The second elastic member 44 is fixedly installed about the fixed shaft 1 between the second opening / closing disk 26 and the filter member 19.

Reference numeral 30 is a backfire detection sensor installed on the gas outflow passage 41 to detect a backfire of the burner and generate a signal. The flashback detection sensor 30 rotates between the supports 31-1 and 31-2 on both sides and expands toward the supports 31-1 and 31-2 as the temperature rises. One side or both sides of the support 32 and one side or both sides of the support 31-1 and 31-2, and the sensors 35-1 and 35-2 attached to the inside of the support plate 31-1 and 31-2 to be above a predetermined temperature. When the sensors 35-1 and 35-2 are in contact with each other by expansion, a signal is transmitted to the controller 80.

Referring to the operation of the load preventing device of the present invention including the configuration as described above are as follows.

Referring to FIG. 3, when gas is supplied to the supply pipe and the valve 61 is opened, the valve detecting unit 60 transmits an opening signal of the valve to the operation unit 70 of the cylinder 3, and the operation unit 70 supplies the cylinder. It works. The gas flows through a plurality of through holes 9 through the gas inflow passage 21, which is a space between the outer body portion 100 and the inner body portion 10 generated by the gas inlet 20 and the first sealing member 22. Pass through the cylindrical member (8) having a. The first sealed disk 16 which initially blocked the upper through hole of the inner body part 10 has a fixed shaft 1 connected to the cylinder 3 by the operation of the cylinder 3 to lift the gas in. Is done. At this time, the second sealing disk 26 which is blocking the upper through hole of the inner body part 10 is pushed down by the second elastic member 44 inserted into the fixed shaft 1 by the pressure of the gas introduced therein. While the gas is introduced, the gas is filtered by the second sealing member 42 by filtering tar and other foreign substances contained in the gas component by the filter member 19 inserted into the fixed shaft 1. The gas flow passage 41, which is a space between the generated outer body portion 100 and the inner body portion 10, passes through the gas outlet passage 41 to supply fuel gas to a burner at a place of use.

On the other hand, when the initial gas is ignited in the supplied gas or abnormal pressure of the inlet gas due to micro-explosion by unburned, backflow is made by the backfire prevention device. The second sealing disk 26 is pushed upward by the pressure of the gas flowing back to the lane, and closes the gas flowing in close contact with the inner main body 10 to block further gas supply to the combustion unit. Done. In addition, when the flame caused by the explosion in the combustion unit flows back through the gas supply pipe 5, the flame directly hits the flame detection sensor 35 installed on the gas discharge passage 41 or the heat is generated by the heat of the flame. Transmitting a signal to the control box 80 to operate the cylinder (3) to push the fixed shaft (1) downward while the first sealing disk 16 is in close contact with the upper through hole of the inner body portion 10 to block the inlet gas To prevent backfire and prevent further backfire in the combustion section. Looking at the operation process of the flame sensor 35, the rotating plate 32 that rotates between the two support (31-1, 31-2) is a bimetal material of about 75 ℃ or more expands and thereby the side of the rotating plate The sensor 35-1 attached thereto is in contact with the sensor 35-2 attached to the inside of the support, thereby transmitting a signal to the controller 80.

By the above operation, the flashback prevention aimed at by this invention is achieved.

As described above, the flashback prevention device of the present invention overcomes the problems of the flashback prevention device, which has been used in the conventional annealing furnace, and prevents equipment downtime due to the copper plate bursting or inoperation during abnormal pressure generation due to flashback. Tar and foreign substances contained in the gas introduced by the filter member were filtered to remove the blockage of the burner and various nozzles of the combustion section.Reduction pressure due to backfire is firstly reduced by the filter member and secondly, By blocking the inlet gas by opening and closing action, it prevents the burnout of equipment before gas supply pipe part effectively and detects the flame pushed back by explosion in the combustion part by flame detection sensor installed on gas outflow passage. As soon as the gas inlet is blocked, it can prevent further backfire.

Claims (4)

In the flashback prevention device installed in the gas inlet pipe 5 of the annealing furnace, the inlet 20 and the outlet 40 of the gas connected to the gas inlet pipe 5 and the fixed shaft (1) perpendicular to the center (1) External body portion 100 penetrates and is sealed by the cover portion 4 at the top; A cylindrical member (8) installed below the cover part (4) around the fixed shaft (1) and having a plurality of through holes (9); An inner main body portion 10 installed below the lower end of the cylindrical member 8 inwardly of the outer main body portion 100 and having a through hole vertically; The outer body part 100 and the inner body part 10 are physically fixed to each other and the gas inlet passage 21 and the gas outlet passage in the space between the outer body portion 100 and the inner body portion 10 ( A first sealing member 22 and a second sealing member 42 separating and forming 41; A cylinder 3 for lifting the fixed shaft 1 upward by a signal from the controller 70; A first opening / closing disk 16 and a second opening / closing disk 26 which are fixedly connected to the fixed shaft 1 at a center thereof and open and close the upper through holes of the inner body part 10 from above and below, respectively; A filter member 19 fixedly connected to a lower portion of the fixed shaft 1 by a nut 25 at the center thereof and cut in the lower inner wall of the inner body portion 10 to cover the lower through hole of the inner body portion 10. ); The first elastic member 33, the second opening / closing disk 26 and the filter member installed between the cover part 4 and the first opening / closing disk 16 about the fixed shaft 1. 19, a second elastic member (44) installed around the fixed shaft (1) between; And Flashback prevention device is installed on the gas outflow path 41 and comprises a flashback detection sensor 30 for generating a control signal by detecting a flashback of the burner. The apparatus of claim 1, wherein the cover part (4) and the outer body part (100) are coupled by a bolt member (29) to enable separate assembly. The method of claim 1, wherein the first elastic member 33 is coupled by a nut member 14 between the lower portion of the first elastic member 33 and the upper portion of the first opening and closing disk 16 is in close contact with the first elastic member 33. Flashback prevention device characterized in that it further comprises an elastic member contact plate (13). The rotating plate (30) of claim 1, wherein the backfire detection sensor (30) rotates between the supports (31-1, 31-2) on both sides and expands toward the supports (31-1, 31-2) as the temperature increases. 32), and one side or both sides of the rotating plate 32 and the sensors (35-1, 35-2) attached to one side or both sides of the support (31-1, 31-2) inside the predetermined temperature or more Flashback device, characterized in that the sensor (35-1, 35-2) is in contact with the expansion of the rotating plate (32).