CN106914708B - Laser twin-wire indirect arc composite welding apparatus and wire feed rate predict calculation method - Google Patents

Abstract

The invention relates to a laser twin-wire indirect arc hybrid welding device and a wire feeding speed prediction calculation method, which belong to the technical field of laser-melting electrode arc hybrid welding. The invention aims to solve the problem that it is difficult to determine the relative position adjustment of the double wire and the laser spot and the wire feeding speed in the laser-twin-wire indirect arc hybrid welding method. Its device includes a polarity-changing welding power supply, a laser welding head, a first welding wire position adjustment mechanism, a second welding wire position adjustment mechanism, a first wire feeding mechanism, a second wire feeding mechanism, a first welding wire and a second welding wire. Before welding, adjust the first welding wire position adjustment mechanism and the second welding wire position adjustment mechanism, so that the first welding wire, the second welding wire and the laser beam are in the same plane, so that the first welding wire and the second welding wire intersect at the laser spot; the welding process Among them, the first welding wire and the second welding wire are respectively connected to the two poles of the variable polarity welding power supply to form a current loop. The invention is used in laser-twin-wire indirect arc hybrid welding.

Description

Laser twin-wire indirect arc hybrid welding device and wire feeding speed prediction calculation method

technical field

The invention relates to a laser-twin-wire indirect arc compound welding device and a wire feeding speed prediction calculation method, which is a laser-arc compound welding method and belongs to the field of welding technology.

Background technique

Welding technology is an indispensable processing technology in modern manufacturing and industrial production processes. The current demand for high-quality and efficient welding technology is becoming stronger and stronger. The main way to achieve high-efficiency welding is to increase the welding speed and deposition speed, but the improvement of these two aspects ultimately comes down to the increase of the welding current, and with the increase of the welding current, the welding heat input will inevitably increase, resulting in the deterioration of the welding quality. decline.

Laser-twin-wire indirect arc combination is a new type of high-efficiency welding method. It combines laser and twin-wire indirect arc as two heat sources. The indirect arc is used to melt the double welding wire to form molten droplets alternately, and the laser is used to irradiate the molten droplets to promote its smooth transition. , which can realize the decoupling control of heat input and deposition speed in the welding process. However, this welding method has the problems that the relative position adjustment of the twin wires and the laser spot needs precise adjustment and the wire feeding speed is difficult to determine.

Contents of the invention

The present invention aims to solve the problems that the relative position adjustment of the twin wires and the laser spot needs precise adjustment and the wire feeding speed is difficult to determine in the laser-twin-wire indirect arc hybrid welding method, and provides a laser-twin-wire indirect arc hybrid welding device and Wire feed speed prediction calculation method.

The invention includes a polarity-changing welding power supply, a laser welding head, a first welding wire position adjustment mechanism, a second welding wire position adjustment mechanism, a first wire feeding mechanism, a second wire feeding mechanism, a first welding wire, and a second welding wire.

A laser-twin-wire indirect arc composite welding device according to the present invention includes a polarity-changing welding power supply, a laser welding head, a first welding wire position adjustment mechanism, a second welding wire position adjustment mechanism, a first wire feeding mechanism, a second welding wire Wire feeding mechanism, first welding wire, second welding wire.

The polarity-changing welding power source forms a loop with the first welding wire and the second welding wire, and an indirect arc is formed between the ends of the first welding wire and the second welding wire;

The first welding wire position adjustment mechanism and the second welding wire position adjustment mechanism can adjust the position of the first welding wire and the second welding wire in the same plane as the laser beam along the three directions of X, Y and Z, and can adjust the clamping of the first welding wire and the second welding wire The angle makes the ends of the double wire intersect at point O at the laser spot.

The polarity-changing welding power supply is an AC pulse power supply with constant current output characteristics.

The wire feeding speed prediction calculation method of the laser-twin-wire indirect arc hybrid welding device includes the following two stages:

The first stage:

The polarity-changing welding power supply has constant current output, P is extremely positive, and N is extremely negative. At this time, an indirect arc is formed between the first welding wire and the second welding wire. According to the melting speed of the anode welding wire in the double-wire indirect arc, va is less than the melting speed of the cathode welding wire The characteristics of vc and the technical characteristics of the first welding wire and the second welding wire alternately forming molten droplets at the laser spot O , cathode melting speed vc, and wire feeding speed v are: cathode melting speed vc>wire feeding speed v>anode melting speed va, then the feeding speed of the first welding wire as the anode is v1=v-va, the first The withdrawal speed of the second welding wire as the cathode is v2=vc-v. At this stage, the droplet at the end of the first welding wire is sent to the laser spot O, and the laser is turned on to assist the transition of the droplet;

second stage:

Variable polarity welding power supply (1) Constant current output, polarity conversion between the first welding wire and the second welding wire, the withdrawal speed of the first welding wire as the cathode v1=vc-v, and the feeding speed of the second welding wire as the anode v2=v -va, at this stage, the droplet at the end of the second welding wire is sent to the laser spot O, and the laser is turned on to irradiate the droplet to assist its transition;

The above-mentioned first stage and second stage constitute a dynamic process in which the first welding wire and the second welding wire alternately form molten droplets at the laser spot O in an AC cycle. -va=vc-v, from this formula, the wire feeding speed can be predicted and calculated v=1/2×(va+vc).

Principle of the present invention:

Through the actual welding test, it is found that in the laser-twin-wire indirect arc hybrid welding, the range of wire feeding speed that can make the droplet alternately appear at the intersection of the two welding wires (point O) is relatively small, and it is difficult to determine. Therefore, the calculation method of the wire feeding speed described in the patent is produced.

For the two welding wires in variable polarity twin-wire indirect arc welding, the welding wire connected to the negative pole of the welding power supply is the cathode, and the welding wire connected to the positive pole of the welding power supply is the anode. According to the welding arc theory, the melting speed of the cathode is greater than the melting speed of the anode, and double synchronous wire feeding is set. The speed is between the cathode and anode melting speeds, so that with the change of the current polarity, the welding wires on both sides will alternately appear in the process of cathode welding wire retraction and anode welding wire feeding, and there will be molten droplets appearing alternately at point O , under the action of laser evaporation reaction force to achieve droplet transfer.

The cathode and anode melting speeds of welding wire with a certain composition can be calibrated in advance, and the double synchronous wire feeding speed can be calculated according to the formula in the right to realize the above process.

The present invention can obtain following beneficial effect:

The welding device and the wire feeding speed prediction calculation method of the present invention realize the flexible adjustment of the relative position of the ends of the double wires and the laser spot, ensuring that the ends of the double wires can be accurately fed to the laser spot O point, and the welding wires can be used as anodes respectively And the melting speed of the cathode, predict and calculate the wire feeding speed, which has the advantages of simple design, convenient operation and easy implementation.

Description of drawings

Fig. 1 is a schematic diagram of the principles of the laser-twin-wire indirect arc hybrid welding device and the wire feeding speed prediction calculation method of the present invention.

In the figure: 1 is the polarity-changing welding power supply, 2 is the laser welding head, 3-1 is the first welding wire position adjustment mechanism, 3-2 is the second welding wire position adjustment mechanism, 4-1 is the first wire feeding mechanism, 4 -2 is the second wire feeding mechanism, 5-1 is the first welding wire, and 5-2 is the second welding wire.

Detailed ways

The equipment used in this embodiment includes: polarity-changing welding power supply 1, laser welding head 2, first welding wire position adjustment mechanism 3-1, second welding wire position adjustment mechanism 3-2, first welding wire 5-1, second welding wire 5-2. The first welding wire 5-1 and the second welding wire 5-2 are adjusted by the first welding wire position adjustment mechanism 3-1 and the second welding wire position adjustment mechanism 3-2 to be coplanar with the laser beam and to intersect at point O along the feeding direction.

The first welding wire 5-1 and the second welding wire 5-2 are ER50-6 carbon steel welding wires with a diameter of 1.2mm, and the output current of the variable polarity welding power supply is a square wave waveform with a current amplitude of 100A. When the current is 100A, the anode melting speed va of the first welding wire 5-1 and the second welding wire 5-2 is calibrated to be 2.4m/min, and the cathode melting speed vc is 4.6m/min, according to the formula v= 1/2×(va+vc) can calculate the wire feeding speed v as 3.5m/min. At this wire feeding speed, the first welding wire 5-1 and the second welding wire 5-2 can alternately form molten droplets at the laser spot O within one AC cycle.

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, without departing from the concept of the present invention, its architecture can be flexible and changeable, and series of products can be derived. Just making some simple deductions or replacements should be deemed to belong to the scope of patent protection of the present invention determined by the submitted claims.

Claims (3)

1. a kind of laser-twin-wire indirect arc composite welding apparatus, which is characterized in that it includes variable polarity welding power supply (1), swashs Flush weld connector (2), the first welding wire position adjusting mechanism (3-1), the second welding wire position adjusting mechanism (3-2), the first wire feeder (4-1), the second wire feeder (4-2), the first welding wire (5-1), the second welding wire (5-2)；

Variable polarity welding power supply (1) and the first welding wire (5-1) and the second welding wire (5-2) forming circuit, the first welding wire (5-1) and the Indirect arc is formed between the end of two welding wires (5-2)；

First welding wire position adjusting mechanism (3-1) and the second welding wire position adjusting mechanism (3-2) can be adjusted along tri- directions X, Y, Z First welding wire (5-1), the second welding wire position (5-2) and laser beam are in same plane, adjust the first welding wire (5-1), second The angle of welding wire (5-2) makes mariages intersect at O point at laser facula along feeding direction.

2. laser according to claim 1-twin-wire indirect arc composite welding apparatus, which is characterized in that the Variable Polarity The source of welding current (1) is AC pulse power supply.

3. application laser as described in claim 1-twin-wire indirect arc composite welding apparatus carries out wire feed rate and predicts calculating side Method, which is characterized in that it includes the following two stage:

First stage:

Variable polarity welding power supply (1) constant current output, P is extremely positive, N extremely cathode, at this point, in the first welding wire (5-1) and second Indirect arc is formed between welding wire (5-2), it is molten less than cathode welding wire according to twin-wire indirect arc Anodic welding wire melting rate va The characteristic and the first welding wire (5-1) for changing speed vc replace the technology that molten drop is formed at laser facula O point with the second welding wire (5-2) Feature determines anode melting speed va, cathode burn-off rate vc, the relationship between wire feed rate v three are as follows: cathode burn-off rate Vc > wire feed rate v > anode melting speed va, then feed rate v1=v-va of the first welding wire (5-1) as anode, the second weldering Pumpback speed v2=vc-v of the silk (5-2) as cathode, the molten drop of this end the first welding wire of stage (5-1) are sent to laser light Spot O point opens laser irradiation molten drop and assists its transition；

Second stage:

Variable polarity welding power supply (1) constant current output, the first welding wire (5-1) and the second welding wire (5-2) dipole inversion, the first welding wire The pumpback speed v1=vc-v of (5-1) as cathode, feed rate v2=v-va of the second welding wire (5-2) as anode, this rank The molten drop of section end the second welding wire (5-2) is sent to laser facula O point, is opened laser irradiation molten drop and is assisted its transition；

Above-mentioned first stage and second stage constitute the first welding wire (5-1) and the second welding wire (5-2) alternating in an ac cycle The dynamic process of molten drop is formed in laser facula O point, this process is presented in periodically bilateral symmetry, must make v1=v2, i.e. v-va =vc-v, thus formula prediction calculate wire feed rate v=1/2 × (va+vc).