Welding pad, system and method of use

Abstract

The present invention discloses a welding pad, a system and a method of use. The present invention provides a second groove and a ventilation hole on the pad block, adopts the ventilation hole as a gas passage, and passes the gas in the ventilation hole into the entire groove supporting the weld through the second groove, thereby realizing effective gas transmission and ensuring the gas protection effect; and the system of the present invention directly connects the welding pad to a circulation loop, and at the same time performs purity detection on the gas in the circulation loop to ensure that qualified gas is used for the protection of the back side of the weld, and at the same time accurately controls the amount of protective gas through pressure detection and a circulation pump.

Description

Technical Field

[0001] The invention relates to a welding pad, a system and a use method, and belongs to the technical field of stainless steel welding. Background Art

[0002] For commonly used carbon steel, due to its low alloying element content, only frontal gas shielding is required to ensure weld quality. However, for materials with higher alloying element content, such as stainless steel, backside gas shielding can effectively prevent the burnout of key alloying elements, thereby ensuring the overall quality of the weld. Welding pads are commonly used as auxiliary welding devices for single-sided welding and double-sided forming. They effectively support the molten pool and prevent molten metal from falling. During welding, shielding gas must be transferred to the weld, and existing shielding gas transfer methods are relatively complex. Summary of the Invention

[0003] The present invention provides a welding pad, a system and a method of use, which solve the problems disclosed in the background art.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A welding backing comprises a covering layer and an adhesive layer which are arranged opposite to each other, and a plurality of backing blocks arranged in sequence are arranged between the covering layer and the adhesive layer;

[0006] A first groove is provided on the surface of the gasket block covered with the covering layer, a second groove is provided on one end surface of the gasket block, the second groove is connected to the first groove, and a ventilation hole is provided in the gasket block which is parallel to the first groove and connected to the second groove;

[0007] The first grooves of all gasket blocks are spliced ​​into a whole groove that supports the weld; among two adjacent gasket blocks, the end face of one gasket block with the second groove is in abutment with the end face of the other gasket block without the second groove, and the ventilation hole of one gasket block is connected to the whole groove and to the ventilation hole of the other opposite gasket block through the corresponding second groove.

[0008] If all the lining blocks have one ventilation hole, the ventilation hole is located directly below the first groove.

[0009] If all the gasket blocks have two ventilation holes, the two ventilation holes are parallel and located on both sides of the first groove, the thickness of the gasket block between the two second grooves is smaller than the width of the first groove opening, the symmetry center plane of the gasket block and the first groove is the same plane, and a third groove connected to the first groove is provided on the gasket block between the two second grooves, and the first grooves of the two adjacent gasket blocks are connected through the third groove.

[0010] A marking line for marking the entire groove is provided on one side of the covering layer away from the lining block.

[0011] The covering layer is a low melting point covering layer.

[0012] The covering layer is a low-melting-point inorganic covering layer or a low-melting-point metal foil.

[0013] A welding backing system comprising a gas cylinder, a gas control device and a welding backing;

[0014] The gas control device includes a controller, a first gas inlet, a second gas inlet, a gas outlet and an exhaust port. The gas outlet of the gas cylinder is connected to the first gas inlet, the first gas inlet is connected to the gas outlet, the gas outlet and the second gas inlet are respectively connected to the ventilation holes of the gasket blocks on both sides of the welding gasket, the gas outlet and the second gas inlet are communicated, the exhaust port is connected to the second gas inlet, and the second gas inlet is provided with a purity detector for detecting gas purity and a pressure gauge for detecting gas pressure;

[0015] The ventilation channel between the gas outlet and the second gas inlet, the ventilation channel in the welding pad, and the ventilation channel between the gas control device and the welding pad constitute a circulation loop, and a gas pumping device is provided on the circulation loop;

[0016] The controller controls the opening and closing of the gas outlet and the second gas inlet, the opening and closing of the first gas inlet and the gas outlet, the opening and closing of the exhaust port and the second gas inlet, and the pumping device according to the detected gas purity and pressure.

[0017] The first air inlet is connected to the air outlet via an air inlet valve, the second air inlet, the air outlet and the exhaust port are connected via a three-way valve, and a gas pumping device is provided between the air outlet and the three-way valve. A method for using a welding backing system includes:

[0018] 1) Apply film on both sides of the welding pad and install the welding pad system;

[0019] 2) Open the gas cylinder. The controller controls the opening and closing of the gas outlet and the second gas inlet, the opening and closing of the first gas inlet and the gas outlet, the opening and closing of the exhaust port and the second gas inlet, and the pumping device according to the detected gas purity and pressure.

[0020] Open the gas cylinder. The controller controls the opening and closing of the gas outlet and the second gas inlet, the opening and closing of the first gas inlet and the circulation loop, the opening and closing of the exhaust port and the second gas inlet, and the pumping device according to the detected gas purity and pressure, including:

[0021] 21) Open the gas cylinder, and the controller opens the ventilation channel between the gas cylinder and the gas outlet, closes the ventilation channel between the gas outlet and the second gas inlet, and opens the ventilation channel between the second gas inlet and the exhaust port;

[0022] 22) When the gas purity of the circulation loop is not less than the purity threshold, the controller opens the ventilation channel between the gas outlet and the second gas inlet, and closes the ventilation channel between the second gas inlet and the exhaust port;

[0023] 23) When the gas pressure in the circulation loop is not less than the pressure threshold, the controller closes the ventilation channel between the gas cylinder and the gas outlet;

[0024] 24) The controller starts the pumping device to circulate the gas in the circulation loop;

[0025] 25) After pumping for a period of time, when it is detected that the gas pressure is less than the pressure threshold, the controller opens the ventilation channel between the gas cylinder and the gas outlet until the gas pressure in the circulation loop is not less than the pressure threshold.

[0026] The beneficial effects achieved by the present invention are as follows: 1. The present invention sets a second groove and a ventilation hole on the gasket block, uses the ventilation hole as a gas channel, and passes the gas in the ventilation hole into the entire groove supporting the weld through the second groove, thereby realizing effective transmission of protective gas in a simple form and reducing the difficulty of the process; 2. The present invention uses a low-melting-point covering layer to cover the first groove, and gas is only present at the positions where welding is being performed and welds have been formed. There will be no gas leakage at other unwelded positions, thereby effectively improving the efficiency of gas use and greatly reducing the cost of the back gas protection process; 3. The system of the present invention directly connects the welding gasket to the circulation loop, and at the same time performs purity detection on the gas in the circulation loop to ensure that qualified gas is used for the protection of the back of the weld, and at the same time accurately controls the amount of protective gas through pressure detection and a circulation pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the welding pad;

[0028] Figure 2 Schematic diagram of welding pad for flat plate butt joint (single hole);

[0029] Figure 3 Schematic diagram of the spacer block for flat plate jointing (single hole);

[0030] Figure 4 Schematic diagram of welding pad for flat plate butt joint (porous);

[0031] Figure 5 Schematic diagram of the spacer block for flat plate jointing (multi-hole);

[0032] Figure 6 Schematic diagram of welding gasket for pipe (single hole);

[0033] Figure 7 Schematic diagram of the liner block for pipe (single hole);

[0034] Figure 8 Schematic diagram of welding backing for pipe (porous);

[0035] Figure 9Schematic diagram of a liner block for pipes (porous);

[0036] Figure 10 Schematic diagram of welding backing for fillet weld (single hole);

[0037] Figure 11 Schematic diagram of the backing block for fillet weld (single hole);

[0038] Figure 12 Schematic diagram of welding backing for fillet weld (porous);

[0039] Figure 13 Schematic diagram of fillet weld backing block (porous);

[0040] Figure 14 Schematic diagram of the welding pad system. Implementation Method

[0041] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0042] like Figure 1 As shown, a welding pad comprises a covering layer 2 and an adhesive layer 3 arranged opposite to each other, and a plurality of pad blocks 1 arranged in sequence are arranged between the covering layer 2 and the adhesive layer 3; a first groove 4 is provided on the surface of the pad block 1 covered with the covering layer 2, and a second groove 6 is provided on one end surface of the pad block 1, the second groove 6 is communicated with the first groove 4, and a ventilation hole 5 is provided in the pad block 1 which is parallel to the first groove 4 and communicated with the second groove 6; the first grooves 4 of all the pad blocks 1 are spliced ​​into a whole groove supporting the weld; in two adjacent pad blocks 1, the end face of one pad block 1 provided with the second groove 6 is abutted against the end face of the other pad block 1 not provided with the second groove 6, and the ventilation hole 5 of one pad block 1 is communicated with the whole groove through the corresponding second groove 6 and is communicated with the ventilation hole 5 of the other opposite pad block 1.

[0043] The present invention provides a second groove 6 and a ventilation hole 5 on the gasket block 1, uses the ventilation hole 5 as a gas passage, and passes the gas in the ventilation hole 5 into the entire groove supporting the weld through the second groove 6, thereby realizing effective transmission of the protective gas in a simple form and reducing the process difficulty.

[0044] Common welding methods include flat plate butt welding, pipe welding and fillet welding. The shapes of the backing blocks 1 used in different welding methods are different, as follows:

[0045] For flat plate butt welding, the liner block 1 is trapezoidal in shape. Figure 3As shown, a gasket block 1 with a single ventilation hole 5 for flat plate jointing is provided. The surface covering the cover layer 2 is the top surface. A first groove 4 is provided in the center of the top surface of the gasket block 1. The ventilation hole 5 provided in the gasket block 1 is located directly below the first groove 4. The second groove 6 is provided vertically. The structure after the gasket block 1 is adhered to the adhesive layer 3 and covered with the cover layer 2 is shown in FIG. Figure 2 The adhesive layer 3 and the covering layer 2 respectively seal the two ends of the second groove 6 , and the gas coming out of the ventilation hole 5 can enter the first groove 4 through the second groove 6 .

[0046] like Figure 5 As shown, a gasket block 1 with double ventilation holes 5 for flat plate docking is provided. A first groove 4 is provided in the center of the top surface of the gasket block 1. Two ventilation holes 5 are parallel and located on both sides of the first groove 4. The thickness of the gasket block 8 between the two second grooves 6 is less than the width of the opening of the first groove 4. The symmetric center plane of the gasket block 8 and the first groove 4 is the same plane. A third groove 7 is provided on the gasket block 8 between the two second grooves 6 to connect with the first groove 4. The first grooves 4 of two adjacent gasket blocks 1 are connected through the third groove 7. The structure after the gasket block 1 is adhered to the adhesive layer 3 and covered with the cover layer 2 is shown. Figure 4 The adhesive layer 3 and the covering layer 2 will seal the side of the second groove 6. Since the thickness of the gasket block 8 is smaller than the width of the opening of the first groove 4, there is a connected gap between the second groove 6 and the first groove 4, that is, the gas coming out of the ventilation hole 5 can enter the first groove 4 through the second groove 6.

[0047] For pipe welding, the liner block 1 is a rectangular body as a whole, with one end of the rectangular body arched and the other end concave (matching the arch), such as Figure 7 The figure shows a liner block 1 with a single ventilation hole 5 for pipes. The surface covering the cover layer 2 is the top surface. A first groove 4 is provided in the center of the top surface of the liner block 1. The ventilation hole 5 provided in the liner block 1 is located directly below the first groove 4. The second groove 6 is vertically arranged on the arched side. The structure after the liner block 1 is bonded to the adhesive layer 3 and covered with the cover layer 2 is shown in FIG. Figure 6 When two gasket blocks 1 are spliced ​​together, the arch of one gasket block 1 can be embedded in the depression of the other gasket block 1, and the gas coming out of the ventilation hole 5 can enter the first groove 4 through the second groove 6.

[0048] like Figure 9As shown, a gasket block 1 with double ventilation holes 5 for pipes is provided. A first groove 4 is provided in the center of the top surface of the gasket block 1. Two ventilation holes 5 are parallel and located on both sides of the first groove 4. The thickness of the gasket block 8 (the arched gasket block 8) between the two second grooves 6 is less than the width of the opening of the first groove 4. The symmetric center planes of the gasket block 8 and the first groove 4 are in the same plane. A third groove 7 is provided on the gasket block 8 between the two second grooves 6 to communicate with the first groove 4. The first grooves 4 of two adjacent gasket blocks 1 are connected through the third groove 7. The structure after the gasket block 1 is adhered to the adhesive layer 3 and covered with the cover layer 2 is shown. Figure 8 When two gasket blocks 1 are spliced ​​together, the gasket block body 8 of one gasket block 1 can be embedded in the recess of the other gasket block 1. Since the thickness of the gasket block body 8 is smaller than the width of the opening of the first groove 4, there is a connected gap between the second groove 6 and the first groove 4, that is, the gas coming out of the ventilation hole 5 can enter the first groove 4 through the second groove 6.

[0049] For fillet weld welding, the backing block 1 is an isosceles triangular prism as a whole. Figure 11 As shown, a liner block 1 with a single ventilation hole 5 for fillet welds is provided. A first groove 4 is provided at the top corner of the liner block 1. The ventilation hole 5 provided in the liner block 1 is located directly below the first groove 4. A second groove 6 is provided vertically. The structure after the liner block 1 is adhered to the adhesive layer 3 and covered with the cover layer 2 is shown in FIG. Figure 10 The covering layer 2 closes one end of the second groove 6 , and the gas coming out of the ventilation hole 5 can enter the first groove 4 through the second groove 6 .

[0050] like Figure 13 As shown, a gasket block 1 with double ventilation holes 5 for fillet welds is provided. A first groove 4 is provided at the top corner of the gasket block 1. The two ventilation holes 5 are parallel and located on both sides of the first groove 4. The thickness of the gasket block 8 between the two second grooves 6 is less than the width of the opening of the first groove 4. The symmetric center plane of the gasket block 8 and the first groove 4 is the same plane. A third groove 7 is provided on the gasket block 8 between the two second grooves 6 to connect with the first groove 4. The first grooves 4 of two adjacent gasket blocks 1 are connected through the third groove 7. The structure after the gasket block 1 is adhered to the adhesive layer 3 and covered with the cover layer 2 is shown. Figure 12 The covering layer 2 closes one end of the second groove 6. Since the thickness of the liner block 8 is smaller than the width of the opening of the first groove 4, there is a connected gap between the second groove 6 and the first groove 4, that is, the gas coming out of the ventilation hole 5 can enter the first groove 4 through the second groove 6.

[0051] Regardless of the structure of the gasket block 1, the covering layer 2 covering the gasket block 1 adopts a low-melting-point covering layer 2, which is generally a low-melting-point inorganic covering layer 2 or a low-melting-point metal foil. This covering layer 2 melts and shrinks during welding, so gas is only present at the positions where welding is being performed and welds have been formed. There will be no gas leakage at other unwelded positions, thereby effectively improving the gas utilization efficiency and greatly reducing the cost of the back gas protection process.

[0052] When using the above-mentioned welding pad, the entire groove needs to be aligned with the weld, and then the welding pad is bonded to the object to be welded using the adhesive layer 3. To facilitate alignment, a marking line for marking the entire groove is provided on the side of the covering layer 2 away from the pad block 1.

[0053] Based on the same technical solution, the present invention also discloses a welding pad system, see Figure 14 , including a gas cylinder 9, a gas control device 10 and the above-mentioned welding pad 11.

[0054] The gas control device 10 includes a controller, a first air inlet, a second air inlet, an air outlet and an exhaust port. The air outlet of the gas cylinder 9 is connected to the first air inlet, the first air inlet is connected to the air outlet, the air outlet and the second air inlet are respectively connected to the ventilation holes 5 of the pad blocks 1 on both sides of the welding pad 11, the air outlet and the second air inlet are connected, and the exhaust port is connected to the second air inlet. The second air inlet is installed with a purity detector for detecting gas purity and a pressure gauge for detecting gas pressure; the ventilation channel between the air outlet and the second air inlet, the ventilation channel in the welding pad 11, and the ventilation channel between the gas control device 10 and the welding pad 11 constitute a circulation loop, and a gas pumping device is installed on the circulation loop, specifically a circulation pump can be used; the controller controls the on and off of the air outlet and the second air inlet, the on and off of the first air inlet and the air outlet, the on and off of the exhaust port and the second air inlet, and the pumping device according to the detected gas purity and pressure.

[0055] The gas in the gas cylinder 9 is argon. The gas cylinder 9 has a capacity of 40 liters, a full bottle pressure of 13-15 MPa, a unit price of 60 yuan / bottle, and can be used for 4.3-5 hours when protected at 20 L / min.

[0056] The opening and closing of the above-mentioned ventilation channel is achieved by a valve. Specifically, the first air inlet is connected to the air outlet through an air inlet valve, the second air inlet, the air outlet and the exhaust port are connected through a three-way valve, and the gas pumping device is installed between the air outlet and the three-way valve.

[0057] Initially, there is no gas in the circulation loop, the controller opens the ventilation channel between the gas cylinder 9 and the gas outlet, closes the ventilation channel between the gas outlet and the second gas inlet, and opens the ventilation channel between the second gas inlet and the exhaust port. When the gas purity of the circulation loop is not less than the purity threshold, the controller opens the ventilation channel between the gas outlet and the second gas inlet, and closes the ventilation channel between the second gas inlet and the exhaust port. When the gas pressure of the circulation loop is not less than the pressure threshold, the controller closes the ventilation channel between the gas cylinder 9 and the gas outlet.

[0058] After ventilation for a period of time, when the gas pressure in the circulation loop is not less than the pressure threshold and the purity is not less than the purity threshold, the controller starts the pumping device to circulate the gas in the circulation loop;

[0059] After pumping for a period of time, when it is detected that the gas pressure is less than the pressure threshold, the controller opens the ventilation channel between the gas cylinder 9 and the gas outlet until the gas pressure in the circulation loop is not less than the pressure threshold.

[0060] The above system directly connects the welding pad 11 to the circulation loop, and at the same time performs purity detection on the gas in the circulation loop to ensure that qualified gas is used to protect the back of the weld, and at the same time accurately controls the amount of protective gas through pressure detection and circulation pump.

[0061] Based on the above system, the present invention also discloses a corresponding applicable method, which is as follows:

[0062] 1) Apply film to both sides of the welding pad 11 and install the welding pad system;

[0063] 2) Open the gas cylinder 9, and the controller opens the ventilation channel between the gas cylinder 9 and the gas outlet, closes the ventilation channel between the gas outlet and the second gas inlet, and opens the ventilation channel between the second gas inlet and the exhaust port;

[0064] The gas can enter the gas control device 10 from 3-A, then flow out from 3-B, enter the welding pad 11, and then return to the gas control device 10 from 3-C carrying impurity gases such as air, and be discharged from the end 3-D;

[0065] 3) After a period of time, when the purity of the gas in the circulation loop is not less than the purity threshold, the controller opens the ventilation channel between the gas outlet and the second gas inlet, and closes the ventilation channel between the second gas inlet and the exhaust port;

[0066] 4) When the gas pressure in the circulation loop is not less than the pressure threshold, the controller closes the ventilation channel between the gas cylinder 9 and the gas outlet;

[0067] 5) The controller starts the pumping device to circulate the gas in the circulation loop and welding can be carried out;

[0068] After welding begins, the cover layer 2 will melt and shrink rapidly under the action of the high temperature of the arc, forming gaps in front of the arc and around the bottom of the molten pool. At this time, gas will overflow from the gaps, achieving effective protection of the root of the molten pool;

[0069] 6) After pumping for a period of time, when it is detected that the gas pressure is lower than the pressure threshold, the controller opens the ventilation channel between the gas cylinder 9 and the gas outlet until the gas pressure in the circulation loop is not lower than the pressure threshold, thereby ensuring the protection effect.

[0070] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A welding pad, characterized in that: It comprises a covering layer and an adhesive layer which are arranged opposite to each other, and a plurality of lining blocks which are arranged in sequence are arranged between the covering layer and the adhesive layer; The covering layer is a low-melting-point covering layer, a first groove is provided on the surface of the liner block covered with the covering layer, a second groove is provided on one end surface of the liner block, the second groove is connected to the first groove, and a ventilation hole is provided in the liner block that is parallel to the first groove and connected to the second groove; The first grooves of all gasket blocks are spliced ​​together to form a whole groove supporting the weld; in two adjacent gasket blocks, the end surface of one gasket block with the second groove is in contact with the end surface of the other gasket block without the second groove, and the ventilation hole of one gasket block is connected to the whole groove and the ventilation hole of the other gasket block opposite through the corresponding second groove; After welding begins, the covering layer melts and shrinks under the action of the high temperature of the arc, forming gaps in front of the arc and around the bottom of the molten pool, and gas overflows from the gaps.

2. A welding pad according to claim 1, characterized in that: If all the lining blocks have one ventilation hole, the ventilation hole is located directly below the first groove.

3. The welding pad according to claim 1, wherein: If all the gasket blocks have two ventilation holes, the two ventilation holes are parallel and located on both sides of the first groove, the thickness of the gasket block between the two second grooves is smaller than the width of the first groove opening, the symmetry center plane of the gasket block and the first groove is the same plane, and a third groove connected to the first groove is provided on the gasket block between the two second grooves, and the first grooves of the two adjacent gasket blocks are connected through the third groove.

4. The welding pad according to claim 1, wherein: A marking line for marking the entire groove is provided on one side of the covering layer away from the lining block.

5. The welding pad according to claim 1, wherein: The covering layer is a low-melting-point inorganic covering layer or a low-melting-point metal foil.

6. A welding backing system, characterized in that: comprising a gas cylinder, a gas control device and a welding backing according to any one of claims 1 to 5; The gas control device includes a controller, a first gas inlet, a second gas inlet, a gas outlet and an exhaust port. The gas outlet of the gas cylinder is connected to the first gas inlet, the first gas inlet is connected to the gas outlet, the gas outlet and the second gas inlet are respectively connected to the ventilation holes of the gasket blocks on both sides of the welding gasket, the gas outlet and the second gas inlet are communicated, the exhaust port is connected to the second gas inlet, and the second gas inlet is provided with a purity detector for detecting gas purity and a pressure gauge for detecting gas pressure; The ventilation channel between the gas outlet and the second gas inlet, the ventilation channel in the welding pad, and the ventilation channel between the gas control device and the welding pad constitute a circulation loop, and a gas pumping device is provided on the circulation loop; The controller controls the opening and closing of the gas outlet and the second gas inlet, the opening and closing of the first gas inlet and the gas outlet, the opening and closing of the exhaust port and the second gas inlet, and the pumping device according to the detected gas purity and pressure.

7. The welding backing system according to claim 6, wherein: The first air inlet is connected to the air outlet through an air inlet valve, the second air inlet, the air outlet and the exhaust port are connected through a three-way valve, and a gas pumping device is provided between the air outlet and the three-way valve.

8. A method for using a welding backing system, characterized in that: include: 1) Apply film to both sides of the welding pad and install the system according to claim 6 or 7; 2) Open the gas cylinder. The controller controls the opening and closing of the gas outlet and the second gas inlet, the opening and closing of the first gas inlet and the gas outlet, the opening and closing of the exhaust port and the second gas inlet, and the pumping device according to the detected gas purity and pressure.

9. The method for using the welding backing system according to claim 8, wherein: Open the gas cylinder. The controller controls the opening and closing of the gas outlet and the second gas inlet, the opening and closing of the first gas inlet and the circulation loop, the opening and closing of the exhaust port and the second gas inlet, and the pumping device according to the detected gas purity and pressure, including: 21) Open the gas cylinder, and the controller opens the ventilation channel between the gas cylinder and the gas outlet, closes the ventilation channel between the gas outlet and the second gas inlet, and opens the ventilation channel between the second gas inlet and the exhaust port; 22) When the gas purity of the circulation loop is not less than the purity threshold, the controller opens the ventilation channel between the gas outlet and the second gas inlet, and closes the ventilation channel between the second gas inlet and the exhaust port; 23) When the gas pressure in the circulation loop is not less than the pressure threshold, the controller closes the ventilation channel between the gas cylinder and the gas outlet; 24) The controller starts the pumping device to circulate the gas in the circulation loop; 25) After pumping for a period of time, when it is detected that the gas pressure is less than the pressure threshold, the controller opens the ventilation channel between the gas cylinder and the gas outlet until the gas pressure in the circulation loop is not less than the pressure threshold.

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