CN-122007551-A - Magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing and control method

CN122007551ACN 122007551 ACN122007551 ACN 122007551ACN-122007551-A

Abstract

The invention discloses a magnetic control narrow gap transverse welding process and a control method based on welding wire arc synchronous oscillation, which relate to the field of automatic welding and comprise the following steps of controlling the arc to oscillate by utilizing an alternating magnetic field driven by a magnetic control power supply, synchronously driving a vibrating coil to generate an alternating magnetic field by utilizing alternating current output by a vibrating power supply, generating periodic electromagnetic force to control welding wires to directionally oscillate by interacting with a bias magnetic field formed by a permanent magnet fixed on a wire feeding tube, keeping the oscillation frequency of the output current of the magnetic control power supply consistent with the current oscillation frequency of the electromagnetic force driving power supply, keeping the phases of the output current and the current oscillation frequency of the electromagnetic force driving power supply synchronous, and enabling the residence time of the arc on the upper groove wall to be longer than that of the lower groove wall by adjusting the pulse width duty ratio of positive and negative half waves of the alternating current.

Inventors

SUN QI
SUN QINGJIE
Han Shangjin
LIU YIBO
YU HONGWU
HOU SHAOJUN
HUANG WENHUA
ZOU YUHAO

Assignees

哈尔滨工业大学（威海）

Dates

Publication Date: 20260512
Application Date: 20260209

Claims (9)

1. The magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing is characterized by comprising the following steps of: S1, controlling an electric arc to swing by using an alternating magnetic field driven by a magnetic control power supply, and synchronously driving a vibration coil to generate an alternating magnetic field by using alternating current output by a vibration power supply, wherein the alternating magnetic field interacts with a bias magnetic field formed by a permanent magnet fixed on a wire feeding tube to generate periodic electromagnetic force so as to control a welding wire to swing directionally; S2, keeping the oscillation frequency of the output current of the magnetic control power supply consistent with the current oscillation frequency of the electromagnetic force driving power supply, and keeping the phases of the two synchronous; S3, the residence time of the arc on the groove wall at the upper side is longer than that at the lower side by adjusting the pulse width duty ratio of the positive and negative half waves of alternating current, and the peak current amplitude of the positive and negative half waves of square wave is adjusted at the same time, so that the upward swing amplitude of the arc is larger than the downward swing amplitude, wherein the pulse width ratio compensates the insufficient heat input at the upper side and the downward flow of a molten pool through the cooperative asymmetric design of the pulse width and the pulse amplitude.
2. The welding wire arc synchronous swinging-based magnetic control narrow gap transverse welding process according to claim 1, wherein the asymmetric swinging mode of the welding wire in the step S3 is that in one swinging period, the upward swinging amplitude is larger than the downward swinging amplitude, the ratio of the upward swinging amplitude to the downward swinging amplitude is larger than 1, a swinging track with a large upper side and a small lower side is formed, and the swinging track cooperates with three stages of synchronous swinging to an upper side groove wall, synchronous swinging to a lower side groove wall and synchronous stay at the bottom of a groove, wherein the swinging amplitude and the stay time of an upper side groove wall area are larger than that of the lower side.
3. The magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing, as set forth in claim 1, characterized in that the welding wire and the arc asymmetrically coordinate swing, in one swing period, is divided into three stages, namely the welding wire and the arc synchronously swing to an upper groove wall, synchronously swing to a lower groove wall and synchronously stay at the bottom of the groove, wherein the swing amplitude and the stay time of the upper groove wall area are larger than those of the lower groove wall area.
4. The welding wire arc synchronous swing-based magnetron narrow gap transverse welding process according to claim 1, wherein the magnetron power supply and the vibration power supply are subjected to frequency synchronization and parameter coordination through a central controller.
5. The magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing according to claim 1, wherein the welding wire swing in the step S1 is driven by a welding wire swing system (2), the welding wire swing system (2) comprises a vibrating coil (201), a permanent magnet and a vibrating power supply, the permanent magnet is fixed on a wire feeding tube, and the vibrating coil (201) is coaxially sleeved on the outer side of the wire feeding tube.
6. The magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing according to claim 5, wherein the vibration coil (201) is formed by densely winding small-diameter enameled wires, and an insulating layer is arranged between a framework of the vibration coil (201) and a wire feeding tube.
7. The magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing according to claim 5, wherein an adjustable mechanical limiting mechanism (202) for restraining and adjusting welding wire swing is arranged in the welding wire swing system (2), and the adjustable mechanical limiting mechanism (202) comprises a pair of independently adjustable limiting blocks which are respectively arranged at two sides of the welding wire swing direction.
8. The welding wire arc synchronous swing-based magnetically controlled narrow gap cross welding process according to claim 1, further comprising a monitoring unit, wherein the monitoring unit is a vision sensor located above the welding area and used for acquiring image information of the molten pool and the arc area in real time.
9. A welding wire swing control method for implementing the magnetically controlled narrow gap cross welding process of any one of claims 1-8, comprising the steps of: parameter presetting and model calculation, namely preliminarily calculating theoretical swing parameters through a preset process model or an empirical formula; B, performing electromagnetic drive primary adjustment, namely primarily adjusting the amplitude and the frequency of alternating square wave current output by the vibration power supply according to the calculation result of the step A, so that the welding wire obtains basic swing driving force when mechanical limit is not added; The method comprises the steps of C, accurately calibrating and cooperatively calibrating mechanical limit, adjusting the positions of two independently adjustable limit blocks in an adjustable mechanical limit mechanism (202), setting an upward swinging mechanical upper limit position and a downward swinging mechanical lower limit position so that the stroke defined by the machinery is equal to the total target amplitude, and realizing the rigid constraint of the asymmetric stroke with large upper part and small lower part; Synchronously adjusting the output current frequency of the magnetic control power supply to be consistent with the output frequency of the vibration power supply so as to realize the synchronization of the swing frequency of the electric arc and the welding wire; E, online monitoring and dynamic compensation control, wherein during the welding process, the welding seam forming characteristics are collected in real time through a visual sensor or a molten pool state monitoring device and used as feedback signals, and an online compensation algorithm based on proportional-integral or fuzzy logic is designed to dynamically fine tune the current amplitude of the vibration power supply or the current asymmetry of the magnetic control power supply so as to inhibit disturbance and maintain the process stability.

Description

Magnetic control narrow gap transverse welding process based on welding wire arc synchronous swing and control method Technical Field The invention relates to an automatic welding technology, in particular to a magnetic control narrow gap transverse welding process based on synchronous swing of welding wire arcs and a control method. Background In the field of manufacturing high-end equipment such as energy power, ship ocean, heavy machinery and the like, welding of thick plate metal structures is a key process for guaranteeing the performance and service life of the whole equipment. The narrow gap welding technology has become the main development direction of thick plate welding because of the remarkable advantages of small groove section, small filling amount of welding materials, low heat input, high welding efficiency, small deformation and the like. Among them, the non-consumable electrode gas shielded welding has unique advantages in narrow gap welding due to the characteristics of stable electric arc, no spatter, high purity of the weld, etc. However, when the narrow gap TIG welding technology is applied to a transverse welding position, several long-standing outstanding problems are faced, namely, firstly, under the action of gravity, molten pool metal is extremely easy to accumulate to the lower side of a groove and even flow down, so that the upper side and the lower side of a welding line are not fused uniformly, the lower side is easy to generate unfused defects, and the upper side is possibly insufficient in penetration due to insufficient heat input. Secondly, the narrow gap groove space is extremely limited, the traditional welding gun swinging mechanism is difficult to penetrate deeply, and the heating and filling of the electric arc and the welding wire on the two side walls are difficult to accurately control. Furthermore, to ensure sidewall fusion, it is often necessary to swing the arc, but how to achieve precise coordination of the filler wire and the swinging arc, avoiding unstable weld formation caused by interference or asynchronization of the two, is a core challenge of process control. To address the above challenges, the prior art has been developed primarily from two directions, namely, introducing a magnetic field control technique to improve the heat distribution by applying an external alternating magnetic field to the arc region to drive the arc to oscillate to scan the groove sidewall. And secondly, developing a swinging wire feeding technology to enable the tail end of the welding wire to swing in the groove so as to improve the distribution of filling metal. The prior art, as retrieved, includes the following: 1) Publication number CN118926658a discloses a magnetron swing indirect arc ultra narrow gap welding device and method, in which the device comprises a welding gun part, a wire feeding part, a magnetron part and an insulating fixing plate. The insulation fixing plate is clamped on the travelling mechanism, and the wire feeding part, the welding gun part and the magnetic control part are fixed on the insulation fixing plate and mutually insulated. The electrode is communicated with the welding power supply cathode through an electrode clamp in the welding gun, and the welding wire is communicated with the welding power supply anode through a wire feeding pipe, a conductive clamping block and a conductive rod. The magnetic field generated in the electrified coil is conducted to the welding area through the magnetic core, and the indirect electric arc periodically swings back and forth towards the two sides of the groove under the action of the transverse alternating magnetic field. According to the invention, on one hand, the characteristic that the workpiece is not connected with electricity can be utilized to avoid arc starting of the side wall, the gap width of the groove is reduced, and the welding efficiency is improved. On the other hand, the periodic swing of the indirect arc can obviously enhance the heating effect of the arc on the side wall of the groove, promote the spreading of molten pool metal to the two sides of the groove, inhibit the defect of non-fusion of the side wall which is very easy to generate in the narrow gap welding process and improve the quality of the joint. 2) Publication number CN117300299A discloses a magnetic control narrow gap welding system and a control method, in which the magnetic control narrow gap welding control method comprises the steps of setting a plurality of welding technological parameters before welding starts, obtaining a plurality of technological parameter feedback values after the welding starts, wherein the plurality of technological parameter feedback values comprise circuit parameters, magnetic field intensity, welding gun distance, welding speed, wire feeding speed and the like, adjusting welding control parameters according to the plurality of feedback values, wherein the welding control parameters comprise a