CN103737158B - A kind of electric arc welding gun with double consumable electrodes and a welding method thereof controlled based on heat input - Google Patents

Abstract

The invention belongs to the field of metal welding, and in particular relates to a double melting electrode arc welding gun based on heat input control and a welding method thereof. It is a dual-metal arc welding torch based on heat input control. The non-melting gas-shielded arc welding torch is fixed on the auxiliary casing, and there are screws on both sides of the auxiliary casing. The screw rod on the adjusting gear assembly and the screw rods on both sides of the auxiliary casing are connected together through a connecting sleeve with internal threads; the two gas shielded arc welding torches of the melting electrode are connected to the gas shielded arc welding torch of the non-melting electrode through the connecting sleeve. sides. The welding torch and its welding method can achieve high deposition rate while reducing the heat input acting on the workpiece, reducing the welding deformation of the workpiece, greatly improving the welding quality, and expanding the welding process specification range. It is a high-efficiency, low-heat input The new welding process has obvious advantages especially in the welding of medium and thick plates.

Description

A dual melting electrode arc welding torch based on heat input control and its welding method

technical field

The invention belongs to the field of metal welding, and in particular relates to a double melting electrode arc welding gun based on heat input control and a welding method thereof.

Background technique

High efficiency is the development direction of current welding technology. To achieve high-efficiency welding, one is to increase the welding speed, but increasing the welding speed is prone to defects such as incomplete penetration, discontinuous weld bead, and undercut; the other is to increase the welding wire deposition rate, but conventional MIG welding (such as MIG/ During MAG welding), increasing the welding wire deposition rate also means increasing the welding heat input, which causes problems such as welding deformation and heat-affected zone expansion.

In order to solve the above problems, Professor Zhang Yuming of the University of Kentucky in the United States proposed a heat input control method, that is, to shunt the welding current before it flows into the base metal, so as to reduce the heat input of the base metal. After the method was proposed, many scholars have carried out related research. For example: Shi Yu from Lanzhou University of Technology has studied the droplet transfer morphology of double-bypass coupled arc aluminum alloy MIG welding, and the results show that double-bypass coupled arc can promote droplet transfer and significantly reduce the critical current of spray transfer; Chinese patent The patent document No. CN201110269628.8 describes a double melting electrode single arc bypass coupling composite welding system and method, including a first welding machine, a second welding machine, a first welding wire and a second welding wire, wherein: the first The anodes of the welding machine and the second welding machine are jointly connected with the first welding wire, and the first welding wire forms an arc with the workpiece; the cathode of the first welding machine is connected with the workpiece; the cathode of the second welding machine is connected with the second welding wire, and the second welding wire No arc is formed with the workpiece; the patent document of US Patent No. US2012012559 describes a welding system for controlling heat input, including the following steps: receiving data, encoding the required heat input range with an upper limit value and a lower heat input value Between the limit values, the level required for the encoding of the received data is changed to a set of variables of the first welding seam variable, and the change of the second welding seam variable is determined to a level welding variable setting; Chinese patent number is CN201841347U The patent document of 2010 records a new type of double-wire welding torch. Two welding torch tail connectors are arranged side by side at the tail of the welding torch cable, and the welding efficiency is improved by the design of outputting two welding wires at the same time.

Most of the above research work is focused on the arc physical characteristics of heat input control technology and the design of twin-wire welding torch. So far, there is no welding torch and its welding method based on heat input control that can be really applied to production practice and give full play to its advantages. where. For this reason, the present invention designs a new type of double melting electrode welding torch based on heat input control, and introduces its welding method.

Contents of the invention

The object of the present invention is to provide a heat input based heat input method based on reducing welding deformation, increasing welding wire deposition rate, improving welding quality, pursuing high energy density and uniform arc shape, realizing stable welding, improving welding process, and reducing spatter. Controlled double melting electrode arc welding torch, the object of the present invention is also to provide a welding method based on heat input control of double melting electrode arc welding torch.

The purpose of the present invention is achieved like this:

A dual melting electrode arc welding torch based on heat input control, consisting of two melting electrode gas shielded arc welding torches and a non-melting electrode gas shielded arc welding torch and a mechanical adjustment structure, the non-melting electrode gas shielded arc welding is fixed on the auxiliary jacket There are screw rods on both sides of the auxiliary casing, and the gas shielded arc welding torch is fixed on the adjusting gear assembly. There is a screw rod at one end, and the screw rods on the adjusting gear assembly and the screws on both sides of the auxiliary casing are connected together through a connecting sleeve with internal threads. ; Connect two gas-shielded arc welding torches on the two sides of the gas-shielded arc welding torch through the connecting sleeve; Two fixed fixtures; the other end of the adjustment gear assembly has a rotating adjustment handwheel, and the metal gas shielded arc welding torch has a sawtooth structure that matches the rotation adjustment handwheel.

The MIG torch is a MIG torch, and the non-MIG torch is a TIG torch.

The gas-shielded arc welding torch of the melting electrode and the gas-shielded arc welding torch of the non-melting electrode are connected to a constant voltage power supply.

A welding method based on heat input control of a double-melting electrode arc welding torch, comprising:

Step 1: Process the parts to be welded into I-shaped, Y-shaped or V-shaped grooves as required, and grind and clean the surfaces on both sides;

Step 2: Place the workpiece on the welding platform, adjust the joint position so that it coincides with the travel route of the tungsten tip of the welding torch, and then fix it with a clamp;

Step 3: Adjust the parameters of the double melting electrode arc welding torch to ensure that the MIG welding torches on both sides are symmetrically placed on both sides of the TIG welding torch, so that the MIG welding torches on both sides are at the same height, and the distance between the tip of the welding wire and the base metal is 2-10mm. The distance between the tungsten electrodes is 2-8mm, and the height between the tungsten electrodes and the workpiece is 3-10mm;

Step 4: Set the welding process parameters: the current of the constant current power supply is between 0-300A, the welding current of the constant voltage power supply is between 50-500A, the welding voltage is 15-30V, and the welding speed is between 10-200cm/min During the period, the MIG torch gas flow rate is 8-30L/min, and the TIG torch gas flow rate is 4-15L/min;

Step 5: Turn on the constant current power supply and constant voltage power supply to ignite the welding arc, so that a stable coupling arc is formed between the MIG welding torch and the TIG welding torch on both sides, and then the welding wire is melted and the workpiece is welded.

The beneficial effects of the present invention are:

1. The welding torch and its welding method can achieve a high deposition rate (2-3 times that of conventional MIG welding) while reducing the heat input acting on the workpiece, reducing the welding deformation of the workpiece, greatly improving the welding quality, and expanding the The welding process specification interval is a new welding process with high efficiency and low heat input, especially in the welding of medium and thick plates.

2. The unique combination of double melting electrodes on both sides and non-melting torch in the middle can form a stable, symmetrical and uniform coupling arc, which has higher energy density, better arc rigidity and more concentrated electromagnetic force distribution. At the same time, the heat source is distributed symmetrically, which reduces welding spatter, improves the shape of the weld seam, and greatly improves the welding quality. It is a stable and practical welding process.

3. This method is essentially a modification of arc welding, so it is also a low-cost and high-efficiency welding method. Applied in welding production, it will greatly improve production efficiency, reduce welding cost and improve welding quality, and can realize high-efficiency, high-quality and low-cost welding, which has great engineering practical value.

4. Due to the characteristics of low welding heat input, high welding wire deposition efficiency, and small welding deformation, the welding torch and its welding method are not only suitable for efficient welding of the same metal materials, but also more suitable for dissimilar metals (such as Ti-Al, Fe- Al, Fe-Mg, etc.) welding or surfacing.

5. The welding process of this system is stable and has strong welding adaptability. According to the actual welding requirements, the welding position can be flat welding or other position welding (such as vertical welding, etc.); The shielding gas for arc welding can be either Ar, CO ₂ or mixed gas, etc., which can be widely used in the welding process of various metal structures.

Description of drawings

Fig. 1 is the composition schematic diagram of welding torch of the present invention;

Figure 2 is a partial enlarged view of the adjustment mechanism;

Fig. 3 is a schematic diagram of a single constant voltage power supply double melting electrode welding method;

Fig. 4 is a schematic diagram of the welding method with double constant voltage power supply and double melting electrodes.

detailed description

The present invention is described in more detail below in conjunction with accompanying drawing:

The present invention relates to a dual melting electrode arc welding torch based on heat input control and its welding method. In order to achieve the purpose, the present invention adopts the following technical solutions:

The welding torch is composed of two MIG arc welding torches (MIG welding torch I, MIG welding torch II) and one non-melting electrode gas shielding arc welding torch (TIG welding torch) and related mechanical adjustment structures. Fix the auxiliary jacket on the TIG welding torch and connect it with the MIG welding torch on both sides through the connecting sleeve. The screw rods between the MIG welding torch and the TIG welding torch on both sides are connected through an auxiliary sleeve with an internal thread. When the sleeve rotates in one direction, the two screw rods approach each other at the same time, and vice versa, and move away at the same time, which can be realized Adjustment of left and right distance between MIG welding torch and TIG welding torch. At the same time, there is a fixed outer pipe thread on the MIG welding torch, and the up and down movement of the MIG welding torch relative to the TIG welding torch is realized by adjusting the handwheel and the adjusting gear assembly. After the adjustment of the distance between the MIG and TIG welding torches is completed, the three welding torches are connected together by a fixing fixture.

In order to ensure the welding effect and give full play to the best effect of the welding torch, it is necessary to ensure that the MIG welding torches on both sides are symmetrically placed on both sides of the TIG welding torch. During welding, the MIG welding torches on both sides can be connected to the positive pole of the same constant voltage welding power supply at the same time, or can be connected to the positive poles of two constant voltage power supplies respectively. At the same time, the TIG welding torch is connected to the negative pole of the constant current power supply. After the arc is ignited, a coupling arc with uniform properties, symmetrical shape, high current density, low arc pressure and stability is formed between the welding torch and the workpiece. The double-wire coupled arc can melt more welding wire in the same time and increase the deposition rate; on the one hand, the TIG welding torch increases the melting current of the welding wire, and on the other hand, it serves as a bypass to shunt a part of the welding current passing through the base metal; MIG welding The torch and TIG welding torch are powered by independent power sources, which have a larger adjustment range of welding parameters. Therefore, the combined welding torch and its welding method can achieve high deposition rate welding (2-3 times that of conventional MIG welding) while reducing the heat input acting on the workpiece, reducing the welding deformation of the workpiece, and greatly improving the welding quality. It expands the range of welding process specifications, and is a new high-efficiency welding process, especially in the welding of medium and thick plates, which has obvious advantages.

After the welding process is adjusted, the device can be used in a similar way to a separate metal arc welding torch, which is very convenient and flexible. The specific implementation steps are as follows:

Step 1: Process the parts to be welded into I-shaped, Y-shaped or V-shaped grooves as required, and grind and clean the surfaces on both sides;

Step 2: Place the workpiece on the welding platform, adjust the joint position so that it coincides with the travel route of the tungsten tip of the TIG welding torch, and then fix it with a clamp;

Step 3: Adjust the parameters of the double melting electrode arc welding torch to ensure that the MIG welding torches on both sides are symmetrically placed on both sides of the TIG welding torch, so that the MIG welding torches on both sides are at the same height, and the distance between the tip of the welding wire and the base metal is 2-10mm. The distance between the tungsten electrodes is 2-8mm, and the height between the tungsten electrodes and the workpiece is 3-10mm;

Step 4: Set the welding process parameters, the welding current of the constant voltage power supply is between 50-500A, the welding voltage is 15-30V, the current of the constant current power supply is between 0-300A, and the welding speed is between 10-200cm/min During the period, the gas flow rate of MIG welding torch is 8-30L/min, and the gas flow rate of TIG welding torch is 4-15L/min;

Step 5: Turn on the welding power supply and ignite the welding arc, so that a stable coupling arc is formed between the MIG torch and the TIG torch on both sides, and then the welding wire is melted and the workpiece is welded.

Fig. 1 is a schematic diagram of the composition of the welding torch of the present invention, which mainly consists of a straight TIG welding torch 1, a MIG welding torch 2 on both sides, a fixing fixture 3, an auxiliary outer cover 7, an adjustment hand wheel 9, an adjustment gear assembly 10 and a connecting sleeve (internal thread )11 and so on. Fix the auxiliary jacket 7 on the straight TIG welding torch 1 and connect it with the MIG welding torch 2 on both sides through the connecting sleeve (internal thread) 11 . Rotating the connecting sleeve (internal thread) 11 can realize the adjustment of the left and right distance between the MIG welding torch 2 and the TIG welding torch 1 ; After the adjustment of the distance between the MIG and TIG welding torches is completed, the three welding torches are connected together by the fixing fixture 3 . The enlarged view of the far, near, high and low adjustment mechanism between the welding torches is shown in the attached drawing 2, and the left and right between the MIG welding torch 2 and the TIG welding torch 1 can be realized by connecting the inner thread 13 of the sleeve and the screw rod 14. distance adjustment.

Figure 3 and Figure 4 are schematic diagrams of specific welding methods of the present invention. According to whether the two melting electrode torches are powered independently, they can be divided into single constant voltage power supply double melting electrode welding method (accompanying drawing 3) and double constant voltage power supply double welding method. MIG welding method (figure 4). In order to ensure the welding effect and give full play to the best effect of the welding torch, it is necessary to ensure that the MIG welding torches on both sides are symmetrically placed on both sides of the TIG welding torch, and the TIG welding torch is connected to the negative pole of the constant current power supply. After the welding process is adjusted, the device can be used in a similar way to an ordinary single-melting electrode arc welding torch, which is very convenient and flexible. The specific welding steps are as follows:

Step 1: Process the part to be welded of the workpiece 17 into I-shaped, Y-shaped or V-shaped grooves as required, and grind and clean the surfaces on both sides;

Step 2: Place the workpiece 17 on the welding platform, adjust the joint position so that it coincides with the traveling route of the tungsten electrode tip of the TIG welding torch, and then fix it with a clamp;

Step 3: Adjust the parameters of the double melting electrode arc welding torch to ensure that the MIG welding torches on both sides are symmetrically placed on both sides of the TIG welding torch, so that the MIG welding torches on both sides are at the same height, and the distance between the tip of the welding wire and the base metal is 2-10mm. The distance between the tungsten electrodes is 2-8mm, and the height between the tungsten electrodes and the workpiece is 3-10mm;

Step 4: Set the welding process parameters: the current of the constant current power supply 15 is between 0-300A, the welding current of the constant voltage power supply 16 is between 50-500A, the welding voltage is 15-30V, and the welding speed is 10-200cm/ Min, MIG torch gas flow rate is 8-30L/min, TIG torch gas flow rate is 4-15L/min;

Step 5: Turn on the constant current power supply 15 and the constant voltage power supply 16 to ignite the welding arc, so that a stable coupling arc is formed between the MIG welding torch and the TIG welding torch on both sides, and then the welding wire is melted to weld the workpiece.

Claims (1)

1. a welding method for the double melt pole electrical arc welding guns controlled based on heat input, auxiliary is outer puts fixing non-melt pole gas Shielded arc welding torch, there is screw rod auxiliary overcoat both sides, regulation gear assembly fix melting pole gas shielded arc welding torch, one end Screw rod, the screw rod on regulation gear assembly is had to be linked together by female branch sleeve with the screw rod of auxiliary overcoat both sides； By branch sleeve, two melting pole gas shielded arc welding torches are connected to the both sides of non-melt pole gas shielded arc welding torch；Molten Change, between pole gas shielded arc welding torch and non-melt pole gas shielded arc welding torch, two stationary fixtures are installed；Regulation gear train The other end of part has rotation adjusting handle, melting pole gas shielded arc welding torch has and rotates the sawtooth knot that adjusting handle matches Structure；

Described melting pole gas shielded arc welding torch is MIG welding torch, and non-melt pole gas shielded arc welding torch is tig torch；

Melting pole gas shielded arc welding torch and non-melt pole gas shielded arc welding torch are connected on constant voltage source, it is characterised in that:

Step 1: the position to be welded of workpiece is processed into I shape, Y shape or V-butt as required, and its both side surface is entered Row polishing and cleaning；

Step 2: be placed on jig by workpiece, adjusts seaming position and is allowed to overlap, so with welding gun tungsten electrode tip track route After utilize fixture to be fixed；

Step 3: adjust double melt pole electrical arc welding gun parameter, it is ensured that both sides MIG welding torch is symmetrically placed in tig torch both sides, makes two Side MIG welding torch is positioned at sustained height, the welding wire of both sides MIG welding torch most advanced and sophisticated away from mother metal distance be 2-10mm, welding wire and tungsten electrode it Between distance be 2-8mm, the tungsten electrode height away from workpiece is 3-10mm；

Step 4: set welding condition: the electric current of constant current source is between 0-300A, and the welding current of constant voltage source exists Between 50-500A, weldingvoltage be 15-30V, speed of welding is between 10-200cm/min, and MIG torch gas flow is 8-30L/min, tig torch gas flow is 4-15L/min；

Step 5: opening constant current source and constant voltage source, ignite welding arc, between such both sides MIG welding torch and tig torch Define a stable coupled arc, and then filler wire, weld workpiece.