KR20010084092A - Method of preheating on welding point and it's apparatus - Google Patents

Abstract

PURPOSE: A method and an apparatus for preheating a welding part are provided to prevent cracking of the welding part when welding a large area of the welding part such as a large scale pipe by preheating the welding part so that a welding matrix is expanded to the expansion range in advance. CONSTITUTION: In a preheating apparatus for preheating a welding part for preventing welding cracking according to the welding expansion which is generated mainly when welding a large scale welding matrix, the apparatus for preheating the welding part comprises a control part (3) having a setting part (71), a comparison part (72), an adjusting part (73), a driving part (74), and a memory part (75); supply gas distribution cans (54) which connect supply valves (14) to a main gas distribution pipe (51) in series, and to which pilot valves (15) and gas amount electronic valves (60) are connected in a row consecutively; a supply gas connection tap that is consecutively installed at supply gas mixing cans (55) to which the series connections are united; a burner gas supplying pipe (4) connected between the supply gas connection tap and the a preheating burner (10); and a sensor (5) installed at the comparison part (72) of the control part (3).

Description

Method of preheating on welding point and it's apparatus

The present invention relates to a welding part preheating method and a device for welding while preventing expansion cracks of the weld, in particular to prevent expansion cracks generated when the welding site is constructed in a relatively wide range of welding, such as large pipes The preheating apparatus used in order to automatically set a preheating temperature appropriate to the welding member and to control the heating heat amount of the preheat burner to be heated to the set preheating temperature and its implementation apparatus.

In the welding part preheating method described in the present invention, a contractor visually judges by heating a welding part directly while carrying a preheat burner or heating while fixing a heating device to a fixing device and reading the temperature of the heating part from time to time. By adjusting the valve of the preheat burner manually to adjust the heating temperature of the preheat burner to an appropriate temperature, the preheat burner was preheated while adjusting the gas supply amount or the distance from the heating part.

In the conventional heating method as described above, the contractor had to wait for the welder at all times because the contractor had to preheat the welding part manually, and the heating temperature of the preheater should be manually read at regular intervals at regular intervals. Even in this construction problem and skilled workers could not expect a uniform preheating effect because the heating temperature applied to the preheating site changes from time to time.

The present invention has been invented to solve all the problems of the conventional preheating method described above, and is composed of a single system that automates all the series of preheating processes. In particular, by checking the preheating temperature of the welding part in real time, the heating amount of the preheat burner is automatically adjusted to be appropriately preheated to the welding temperature of the welding part. It is an object of the present invention to provide a preheating method and apparatus for automatically preheating when preheating is started by calling sample data set according to a material or property of a welding target according to the memory data calculated in advance.

1 is a perspective view of a main part configuration of the present invention;

Figure 2 is a perspective view of the preheating main body of the present invention,

3 is a front view of the main part configuration of the present invention;

4 is a schematic configuration diagram of the present invention;

5 is a perspective view of a gas supply unit of the present invention;

6 is a schematic view of a solenoid valve for gas supply control of the present invention;

7 is a perspective view of the preheat burner of the present invention,

8 is a cross-sectional view of the preheat burner of the present invention.

Explanation of symbols on the main parts of the drawings

One ; Preheating base 2; Main gas pipe

3; Control unit 4; Burner Gas Supply Pipe

5; Sensor 6; Sensor connector

7; Graph output section 8; Temperature setting part

9; Power switch 10; Preheat Burner

11; Burner stand 12; Main gas pressure gauge

13; Supply pressure gauge 14; Supply valve

15; Pilot valve 16; Mover

17; Supply gas connection step 21; Flame nozzle

22; Fireworks signs 23; Burner Gas Supply Hole

24; Bantry Tube 25; Burner valve

26; Hinges 27; Installation hinge

30; Welder 40; Welding tower

50; Supply part 51; Main gas distribution pipe

52; Main gas pressure gauge 53; Gas Inlet Pipe

54; Feed gas distribution tank 55; Supply gas mixture

56; Supply gas pressure gauge 57; Gas Inlet

60; Gas solenoid valve 61; Electronic signal tube

62; Control connector 63; 1st solenoid valve

64; Second solenoid valve 65; Third solenoid valve

66; Inlet distribution pipe 67; Outlet mixing pipe

71; Setting section 72; Comparator

73; Adjusting section 74; Driving part

75; Memory section 100; Pipe

101; Weld 110; Rolling device

The present invention for achieving the above object consists of an electronic control means including a setting unit, a comparison unit, an adjusting unit, a driving unit for storing the sample data and effectively utilizing the sample data, heating fuel supply means, heating means, meter reading means It consists of one construct.

Hereinafter, with reference to the accompanying drawings, the preheating method and the preferred embodiment of the present invention will be described in detail.

1 is a perspective view showing an embodiment of the present invention, and FIG. 3 is a front view showing an embodiment of the present invention, wherein a large amount of gas (LPG, etc.) pumped from the main gas pipe 2 is preheated to the controller 3. The preheating main body 1 which controls the gas supply amount to the burner gas supply pipe 4 so that temperature may be connected, and the preheat burner 10 which receives the gas supplied from the burner gas supply pipe 4 and generates heat quantity are connected.

On the other hand, the pipe pipe 100 for welding is intermittently welded to the welding portion 101 on the jig installed on the ground and then mounted on a plurality of the rolling device 110 and rolled at a speed suitable for welding.

The welding tower 40 is located around the pipe pipe 100 which is placed on the rolling device 110 as described above, and the welding tower 40 is provided with a welding machine 30 having the same automatic welding function as the pipe pipe ( The welding is performed in close proximity to the welding portion 101 of 100.

At this time, the preheat burner 10 fixed to the preheating stand 11 before the welding position of the welding portion 101 is installed at a predetermined distance to generate heat by the gas supplied from the preheating base body 1 to produce a weld portion ( Preheated by heating to 101 to a predetermined preheating temperature.

Then, the set preheating temperature of the welding unit 101 is detected by the sensor 5 and sent to the control unit 3 of the preheating main body to be compared with the temperature set in the control unit 3 to discriminate the difference from the preheating temperature. To adjust the heating amount of the preheat burner 10.

As shown in FIG. 2, the preheating base 1 has the appearance as shown in FIG. 2, and the gas supply unit 50 is provided inside the preheating base 1 as shown in FIG. 5. Is a box form with a moving device 16 installed at the bottom, and a pair of supply gas connecting steps 17 connecting the burner gas supply pipe 4 are exposed on the front side, and the main gas pipe 2 is connected to the left side. The gas inlet 57 and the sensor connector 6 are exposed on the left side and the main gas pressure gauge 12, the graph output unit 7, the temperature setting unit 8, the power switch 9 and the supply pressure gauge ( 13), the supply valve 14, and the pilot valve 15 are laid in the state exposed to the surface.

On the other hand, the main gas distribution pipe 51 having the gas inlet 57 is placed in the entire length of the preheating basic body 1 inside the preheating main body 1 and above the main gas distribution pipe 51. A main gas pressure gauge step 52 is provided which connects the main gas pressure gauge 12 for displaying the pressure of the pumped gas.

In addition, a number of gas inlet pipes 53 are installed in front of each other, and supply valves 15 are successively provided at each of them, and supply gas distribution tanks 54 formed as rectangular box cylinders are installed in succession. 15) and the other side, the gas solenoid valve 60 is branched and installed independently, they are combined in the supply gas mixture cylinder 55 connected in series.

In the front of the supply gas mixing cylinder 55 connected by integrating the pilot valve 15 and the gas volume solenoid valve 60 as described above is provided with a supply gas connecting step 17 for distributing to the two burner gas supply pipe (4) On the upper side, a supply gas pressure gauge step 56 connected to the supply pressure gauge 13 indicating the pressure of the gas sent to the burner gas supply pipe 4 is provided.

On the other hand, the schematic configuration of the gas flow solenoid valve 60 is provided with three independent first solenoid valve 63, the second solenoid valve 64, the third solenoid valve 65 as shown in FIG. Inlet distribution pipe 66 of the independent passage connected to each of the solenoid valves (63, 64, 65) is connected and the outlet mixture pipe to allow the gas passing through the solenoid valves (63, 64, 65) to be combined On one side of the gas flow solenoid valve 60 to which the 67 is connected and including the above-described components, a control connector 62 for receiving a solenoid valve control signal transmitted through the electronic signal tube 61 is provided and the solenoid valve is provided. Control the (63, 64, 65).

The gas supplied by the gas quantity solenoid valve 60 controlled as described above is supplied to the preheat burner 10 connected to the end along the burner gas supply pipe 4. The configuration of the preheat burner 10 is illustrated in FIG. 7. It has the same shape but has a curved surface corresponding to the outer circumferential arc of the pipe 100 to be welded as a whole. In the center of the curved surface, a plurality of flame nozzles 21 are formed at regular intervals and are inclined inwardly on the side thereof. The flame guide plate 22 is installed facing each other while facing.

On the other hand, in the outer center of the curved portion, the banchu tube (24) having the burner valve 25 is screwed into the burner gas supply hole (23) and the burner gas supply pipe (4) is connected to the inlet port. Composed in a single product by a hinge 26 for forming a pair and integrally fixing these preheat burners 10, and install a hinge 27 in one of them and screw in the burner stand 11, which is adjustable in height It is installed by tightening.

In addition, the control part 3 demonstrated in the first half part is provided with the block conceptual operation apparatus of the memory part 75, the setting part 71, the comparison part 72, the adjustment part 73, and the drive part 74. As shown in FIG.

Referring to the operation of the present invention configured as described in more detail as follows.

The overall schematic action structure of the present invention is as shown in Figure 4, the preheat burner 10 for heating and preheating the butt weld portion 101 of the pipe pipe 100 at a predetermined distance to the weld portion 101 Gas (G) supplied to the main gas pipe (2) in the position is located in the operating state is the pressure is filled and filled in the main gas distribution pipe (51).

To start preheating in the standby state as described above, when the supply valve 14 is completely opened, the gas G is filled in the supply gas distribution tube 54, and when the pilot valve 15 is slightly opened, the gas G is supplied. The gas mixture 55 is continuously filled and the gas G reaches the preheat burner 10 along the burner gas supply pipe 4 and is ejected. When the gas G is ignited, the welded portion of the pipe pipe 100 is ignited. The 101 is heated.

When the preheating is started as described above, the heating heat amount of the preheat burner 10 should be set according to the material of the welding base material of the pipe tube 100 and the thickness of the welding part 101, and the setting value is performed by the controller 3.

That is, when the material and the welding amount of the base material to be welded are set in the setting unit 71 of the control unit 3, the preheating sample data corresponding to the set value is extracted from the memory unit 75, and the preheating setting is automatically performed. The setting signal is transmitted to the comparator 72.

The preheat setting value received from the setting unit 71 is stored in the internal memory in the comparison unit 72 and the preheating temperature of the welding unit 101 is read from the sensor 5 connected to one side and stored in the internal memory. Compare with preheat setting value.

At this time, when the preheating temperature of the welding unit 101 is lower than the set value, the low signal is sent to the adjusting unit 75, and the adjusting unit 75 receiving the low signal is internally converted into an electrical signal and then converted into an electric signal to the driving unit 74. Send it.

The driving unit 74 receiving the electrical signal as described above opens the solenoid valve installed inside the gas quantity solenoid valve 60 by the primary signal to supply the gas G filled in the supply gas distribution tube 54. It is sent to the mixing barrel (55).

In this case, the supply gas mixture 55 is mixed with the gas G supplied through the pilot valve 15 to receive more gas G, and the mixed gas G is bisected. By feeding the burner gas supply pipe 4 in the same amount, the amount of gas G supplied to the preheat burner 10 also increases, thereby increasing the amount of heat for heating the welding part 101.

On the other hand, when the preheating temperature read from the sensor 5 proximate to the welding part 101 is higher than the set value set in the setting part 71, the preheating temperature detected from the sensor 5 in real time by the comparator 72 and In the process of comparing the setting values of the setting unit 71 is checked, when a high signal is sent to the adjusting unit 73 to lower the heating amount of the preheat burner 10, the adjusting unit 73 subtracts a signal from the previously received signal by one step. The gas is supplied to the preheat burner 10 by reducing the amount of gas G sent to the supply gas mixing cylinder 55 by closing the open solenoid valve in the driving unit 74 when it is sent to the driving unit 74. By lowering the amount of the heating heat of the preheat burner 10 is lowered.

The series of operations acting as described above is continuously circulated to automatically adjust the amount of gas G supplied to the preheat burner 10 so that the preheating temperature set by the setting unit 71 is kept constant. It is to adjust the amount of heating heat applied to the more detailed operation state will be described.

In order to carry out the present invention in detail, first, the power switch 9 installed on the preheating base 1 is turned on to apply power, and the material and welding of the welding base material to be preheated through the temperature setting unit 8 installed. Preheating temperature should be set according to thickness welding method and shape of welding surface.

The preheating temperature setting method is not specifically described in the present invention, but the electronic control method driven by a general electronic circuit is applied. A feature of the present invention is preheating to an appropriate preheating temperature according to the material and the welding thickness of the welding base material. The heating preheating rate, welding temperature and subsequent cooling time per unit of time are already stored in the memory unit 75 installed in the control unit 3 of the present invention, and the minimum heating of the preheat burner 10 used in the present invention. The amount of change in the preheating temperature per unit time is already calculated and loaded into the memory unit 75 according to the amount of heat and the maximum heating heat, and the user simply sets the setting temperature unit 8 to automatically change the memory unit 75. Operation to take out the appropriate sample data loaded on the panel and start preheating according to the set value of the sample data. This is to begin.

When the operation is started by setting the appropriate preheating temperature as described above, the change in the preheating temperature of the overall preheating process is displayed in real time, which is displayed in the form of a graph in the graph output unit 7 so that the preheating of the welding unit 101 is preheated. The process of reaching the temperature can be easily determined.

On the other hand, since the pipe pipe 100 of the base material to be welded is a large pipe, the welding portion 101 has a thickness of 150 mm to 300 mm to weld a wide range of spaces, and thus cannot be welded at a time, thereby welding back and forth several times.

Therefore, the temperature of the base material of the weld part 101 is increased to a considerably high temperature, thereby deforming the weld base material, and when welding is performed only, cracks are generated in the weld part due to a sudden difference between the welding temperature and the cooling temperature.

As the preheating method described in the present invention is performed for the purpose of preventing cracks in the welded part as described above, the preheating of the welded part 101 is performed in advance to offset the sudden rise by welding, and also rapid cooling after welding. In order to prevent the installation of the preheat burner 10 to the rear end of the welding portion 101 by installing in such a way as to gradually reduce the heating calories it is possible to prevent the expansion cracks of the weld.

The control method for preheating the present invention as described above will be described in more detail.

The present invention has been described that the main function is to control the heating calorie of the preheat burner 10 for preheating the weld portion 101, as described above, and the preheat temperature of the weld portion 101 is detected by the sensor 5 and the detection thereof. The preheat burner may be mechanically controlled by adjusting the gas amount solenoid valve 60 installed in the gas supply unit 50 by the control unit 3 that determines the temperature and the predetermined set temperature set in the setting unit 71 by comparing the unit 72. 10) the amount of gas G to be supplied is adjusted.

Referring to the gas G supply path and the function of the gas supply unit 50, the gas G pumped into the main gas pipe 2 is charged into the main gas distribution pipe 51 through the gas inlet 57. In a state where a gas supply inlet pipe 53 for supplying gas G to a plurality of preheat burners 10 is installed, mechanisms of the same components are sequentially arranged in each of the gas supply inlet pipes 53. As it is installed to each independently drive to adjust the amount of heat of the preheat burner (10) connected to the final end.

Therefore, in order to adjust the preheat burners 10, a control channel for controlling the plurality of preheat burners 10 is provided inside the control unit 3, and the description will be made by the plurality of channels performing the same function. The operation of the operation by one channel and the operation of controlling the preheat burner (10) connected to one gas supply inlet pipe (53).

The gas G drawn from the gas inlet pipe 53 is supplied to the supply gas distribution tube 54 while being interrupted by the supply valve 14.

As described above, the gas G supplied to the supply gas distribution tube 54 is a pilot valve 15 for adjusting only a minimum amount of heat from the preheat burner 10 and a gas amount solenoid valve for supplying more gas G. The gas (G) is then mixed in a feed gas mixing cylinder (55) connected next, and the gas (G) is supplied to the preheat burner (10) composed of a pair of burners at the same pressure, respectively. It flows to the supply gas connection step 17 which connects as much as possible.

That is, when the operation of starting the initial preheating in the preheating base body 1 starts, the flow of the gas G passes through the supply valve 14 through the gas inlet pipe 53 and enters the supply gas distribution tube 54, but the amount of gas is increased. Since the solenoid valve 60 is in a closed state, the solenoid valve 60 flows into the supply gas mixing cylinder 55 through the pilot valve 15 only, and is then supplied to the two supply gas connection steps 17 at a uniform pressure to burner gas supply pipe ( Flow along 4) is finally supplied to the preheat burner (10).

As described above, the initial flow of the gas G may generate a minimum amount of heat generated from the preheat burner 10 and also prevent the fire flame ignited in the preheat burner 10 from being extinguished.

In this way, the preheat burner 10 generates the minimum amount of heat. The welding portion 101 is preheated. However, in the case of welding other than a welding base material made of a hard material, the minimum amount of heat does not reach a predetermined preheating temperature within a desired time. .

Therefore, the sensor 5 detects the preheating temperature of the welding part 101 which is gradually heated, and gradually increases the heat amount of the preheat burner 10. The action of the gas amount solenoid valve 60 is as shown in FIG. The first solenoid valve 63, the second solenoid valve 64, and the third solenoid valve 65 are provided therein, and each of the solenoid valves 63, 64, 65 has an inlet distribution pipe 66 having independent condensation. ) And the outlet distribution pipe 67 to control the flow of the gas (G) by driving.

That is, when the sensor 5 detects the preheating temperature of the welding unit 101 and sends it to the control unit 3, the control unit 3 generates a primary drive signal from the drive unit 74 to increase the preheating temperature per unit of time, and the primary The first solenoid valve 63 of the gas flow solenoid valve 60 is opened through the control signal pipe 61.

When the first solenoid valve 63 of the gas flow solenoid valve 60 is opened as described above, the gas G introduced into the supply gas distribution tube 54 is parallel with the pilot valve 15. To supply the gas mixture 55 to the preheat burner 10 by supplying more gas G to the preheat burner 10 than the gas G supplied to the pilot valve 15. Is increased.

In addition, when the preheating temperature of the welding part 101 needs to be made higher, the driving part 74 of the control part 3 generates a secondary signal and the second electron of the gas amount solenoid valve 60 through the control signal tube 61. Open the valve 64.

The second solenoid valve 64 opened as described above supplies gas G more to the supply gas mixture 55 together with the first solenoid valve 63 opened above. The amount of heat is increased and another third solenoid valve 65 attached to the gas quantity solenoid valve 60 may also be opened by the third signal of the controller 3, thereby preheating more gas G. It becomes possible to supply to (10).

On the other hand, the above description has been described the action of increasing the amount of heat of the preheat burner 10 by opening the solenoid valves (63, 64, 65) of the gas flow solenoid valve 60, on the contrary, the heat amount of the preheat burner (10) Reducing action is to block the last drive valve among the open solenoid valves (63, 64, 65) in the reverse order from the last open signal generated in the control section 3 to be supplied through the gas flow solenoid valve 60 ( By blocking G) step by step, the amount of gas G supplied to the preheat burner 10 is forcibly reduced, thereby reducing the heat amount of the preheat burner 10.

As described above, the gas G supplied by the gas amount solenoid valve 60 controlled by the signal of the controller 3 is finally supplied to the preheat burner 10 to generate heat, and the heat is directly transmitted to the welding part 101. Sprayed to preheat.

The preheat burner 10 generating heat as described above has the structure shown in FIGS. 7 and 8, but the gas G supplied from the gas supply unit 50 through the burner gas supply pipe 4 is a burner valve. It is interrupted by (25) and subsequently injected into the banchu tube (24).

The banchu tube 24 has a well-known structure and is supplied to the burner barrel 20 through the burner gas supply hole 23 with fresh air from outside due to the gas G injected thereon, and at regular intervals. After being evenly sprayed into the plurality of flame nozzle 21 can be burned smoothly.

Meanwhile, in front of the flame nozzle 21, the flame guide plates 22 gathered inwardly face each other and are laid opposite to each other. The action of the flame nozzle 21 is to compress and burn the flame burned by the flame nozzle 21 into a row of flames. In addition to effectively contacting the welding portion 101, it is possible to prevent the spark from flying by the unexpected external air flow.

In addition, the preheat burner 10 has a burner bin 20 divided into two by three hinges 26 integrally formed on the rear thereof as a single unit, and is installed at the rear side of the hinge 26 in the middle thereof. The hinge 27 is attached to the burner stand 11 is adjusted to the height of the height is hinged to be able to adjust the height and the front angle arbitrarily.

The present invention which acts as described above is preheated by a control unit having a memory unit loaded with the sample data set the welding preheating temperature suitable for the material properties of the welding base material and the calorie data generated per time unit of the preheat burner to maximize the preheating means. It is possible to automatically carry out the preheating process by installing the integrated electronic control unit inside and controlling the gas supply unit and the sensor to detect the preheating temperature of the welding unit. As a conventional method, the installer completely eliminates the problems of manual preheating, and in particular, improves the structure of the preheat burner and installs a flame guide plate to preheat the weld more effectively, thereby collecting and concentrating the sparks burned in the preheat burner as one. Very warm to weld It is an advanced weld preheating method and apparatus.

Claims (4)

In the welding part preheating method mainly performed to prevent the welding crack caused by the welding expansion generated when welding a large welding base material, The control part equipped with the memory unit that stores the characteristics of the welded base material and the amount of heat generated per unit of time of the preheat burner is stored in real time by detecting the preheating temperature of the welding part from a sensor that detects the preheating temperature of the welding part, and compares the predetermined preheating temperature. And a heat quantity of the preheat burner is directly controlled by directly adjusting a gas quantity solenoid valve for supplying a gas. In the preheating device for preheating the weld part mainly to prevent the welding crack caused by the welding expansion generated when welding a large welding base material, A control unit 3 including a setting unit 71, a comparing unit 72, an adjusting unit 73, a driving unit 74, and a memory unit 75; The pilot valve 15 and the gas quantity solenoid valve 60 are connected in series to the supply gas distribution pipe 54 in which the supply valve 14 is connected in series with the main gas distribution pipe 51; A supply gas connecting step (17) is subsequently installed in the feed gas mixing cylinder (55) which combines the parallel connections into one; A burner gas supply pipe 4 is connected between the supply gas connecting step 17 and the preheat burner 10; Welding unit preheating device, characterized in that the sensor 5 is attached to the comparison unit 72 of the control unit (3). The method of claim 2, The amount of gas provided with the first solenoid valve 63, the second solenoid valve 64, and the third solenoid valve 65 respectively between the inlet distribution pipe 66 and the outlet distribution pipe 67 divided into a plurality of independent passages. Solenoid valve 60; Welding unit preheating device, characterized in that the control connector 62 is installed on one side of the gas flow solenoid valve (60). The method of claim 2, Integrally fixing the burner barrel 20 having a curved rectangular shape at both ends of the plurality of hinges 26; Perforating one burner gas supply hole 23 perforated on a rear surface of each burner barrel 20 to install a banuri tube 24; Drilling a plurality of flame nozzles 21 at equal intervals on the front curved surface of the burner barrel 20; The front side of the burner box 20 is installed to face each other so that the flame guide plate 22 inclined inward to face each other; Welding preheating device, characterized in that the configuration of the preheat burner (10) attached to the hinge (27) installed in the middle rear of the hinge (26).