Abstract: Welded products are lighter than riveted parts, castings and forgings. For transportation vehicles, they can reduce their own weight and save energy. With the continuous development of technology, welding equipment also tends to be automated. What are the automatic welding equipments? According to the degree of automation, automated welding equipment can be divided into the following three categories: rigid automated welding equipment, adaptive control automated welding equipment, and intelligent automated welding equipment. The following introduces you to the classification and composition of automatic welding equipment as well as precautions. Classification of automatic welding equipment According to the degree of automation, automatic welding equipment can be divided into the following three categories:
1. Rigid automated welding equipment Rigid automated welding equipment can also be called primary automated welding equipment, most of which are Designed based on the principle of loop control. Although the entire welding process is automatically completed by the welding equipment, there is no closed-loop feedback system for fluctuations in welding parameters during the welding process, and possible deviations cannot be randomly corrected.
2. Adaptive control of automated welding equipment. Adaptive control of welding equipment is a highly automated welding equipment. It is equipped with sensors and electronic detection circuits to automatically guide and track the weld trajectory. And implement closed-loop feedback control on the main welding parameters. The entire welding process will be completed automatically according to preset procedures and process parameters
3. Intelligent automatic welding equipment uses various advanced sensing elements, such as visual sensors, tactile sensors, auditory sensors and lasers. Scanners, etc., and with the help of computer software systems, databases and expert systems, have the functions of identification, judgment, real-time detection, calculation, automatic programming, welding parameter storage and automatic generation of welding record files.
What are the automatic welding equipments? 1. Automatic straight seam welding machine
The automatic straight seam welding machine is also called the automatic longitudinal seam welding machine. It is used for longitudinal seam welding of cylinders and flat plates. Longitudinal seam butt jointing is a type of automatic welding machine. It can replace labor in large quantities, reduce labor costs, and improve the working environment of welding workers.
2. Automatic circumferential seam welding machine
The automatic circumferential seam welding machine is a general-purpose automatic welding equipment that can complete various circular and circular welding seams. It can be used for high-quality welding of carbon steel, low alloy steel, stainless steel, aluminum and its alloys and other materials, and can be composed of a set of welding power sources such as argon arc welding (with or without wire filler), gas metal arc welding, and plasma welding. Automatic circumferential seam welding system.
3. Automatic pipe welding machine
The automatic pipe welding machine is a machine for automatic pipe welding. It uses the principle of workpiece rotation and gun head fixation to perform welding. Welding in the best position (flat welding position). The models are divided into compression-type automatic welding machines, cantilever-type automatic welding machines, split-type automatic welding machines, rotary automatic welding machines, clamp-type automatic welding machines, etc. The welding methods include TIG, MIG, and SAW, which can be equipped as needed. One gun, two guns and three guns. Automatic pipe welding machine is also called pipe welding machine, pipe welding machine, pipe welding machine, pipe welding machine, automatic pipe welding, and automatic pipe welding in our Qianshan pipeline.
4. Intersecting line automatic welding machine
Using the motor as the main driving mechanism, the control system adopts human-machine interface digital control, supplemented by relay control, thus safely realizing the welding Automatic control, simplified programming, easy to learn.
5. Ultrasonic automatic welding machine
Ultrasonic welding machine can be divided into automatic welding machine, semi-automatic ultrasonic welding machine and manual welding machine according to the level of automation. For modern enterprises, the level of automation The higher it is, the more conducive it is to enterprise assembly line production, so the use of automatic welding machines is a future trend for enterprises.
6. Automatic submerged arc welding machine
Automatic submerged arc welding machine refers to equipment that uses automatic welding under the flux layer. It is equipped with an AC welding machine as the arc power source. It is suitable for Various butt welds, lap welds and fillet welds with or without grooves in the horizontal position or with an inclination of not more than 10 degrees from the horizontal position. Compared with ordinary manual arc welding, it has outstanding advantages such as high production efficiency, good weld quality, saving welding materials and electric energy, small welding deformation and improved working conditions.
7. Electroslag automatic welding machine
The electroslag automatic welding machine uses welding wire as the electrode, and the welding wire is fed into the electroslag pool through a non-consumable electroslag welding gun and a conductive nozzle. welding equipment. The electroslag automatic welding machine is mainly used for efficient welding of vertical welds of steel structures, especially for the welding of box columns and box beam partitions.
8. Laser automatic welding machine
The laser welding machine deposits defects such as wear, scratches, pinholes, cracks, defects and deformations, reduced hardness, and blisters on molds and metal workpieces. , sealing, filling and other repair functions. After repair, the substrate will not be deformed, annealed, undercut, or have residual stress, and its metal structure will not be changed. The repair accuracy is high, and the coating thickness ranges from a few microns to a few millimeters, and only needs to be polished. High-power argon gas protection, can work for a long time. The energy of the laser beam is adjustable, the moving speed is adjustable, and it can be used for various welding processes. Laser welding has a high degree of automation and can be controlled by a computer. It has fast welding speed and high efficiency, and can easily weld any complex shape.
9. Electron beam welding machine
The electron beam welding machine is a relatively sophisticated welding equipment that uses the principle of bombarding the workpiece with a high-speed moving electron beam. It basically The above represents the current highest performance welding level. Vacuum electron beam welding uses a directional high-speed moving electron beam to hit the workpiece during the welding process, converting kinetic energy into heat energy to melt the workpiece and form a weld. The electron beam energy density is as high as 108 W/cm2, which can quickly heat the metal of the weldment to a very high temperature, thus melting any refractory metals and alloys. It does not require filling materials and is generally welded in a vacuum. The weld is pure, smooth and has no oxidation defects.
10. Welding robot
Welding robot is an industrial robot engaged in welding. An industrial robot is a multi-purpose, reprogrammable automatic control manipulator (Manipulator) with three or more programmable axes, used in the field of industrial automation. In order to adapt to different uses, the mechanical interface of the last axis of the robot is usually a connecting flange, which can be connected to different tools or end effectors. The welding robot is a welding clamp or welding (cutting) gun installed on the end shaft flange of the industrial robot, so that it can perform welding, cutting or thermal spraying.
Automatic welding equipment system components Automatic welding equipment includes welding energy equipment, welding head and welding control system.
1. Welding energy equipment is used to provide the energy required for welding. Commonly used are various arc welding power sources, also called electric welding machines. Its no-load voltage is 60~100 volts, the operating voltage is 25~45 volts, and the output current is 50~1000 amps. During manual arc welding, the arc length often changes, causing changes in the welding voltage. In order to make the welding current stable, the external characteristics of the arc welding power source used should be steep drop, that is, as the output voltage changes, the output current should change very little.
Gas metal arc welding and submerged arc welding can use flat characteristic power sources, and their output voltage changes very little when the current changes. Arc welding power sources generally include arc welding transformers, DC arc welding generators and arc welding rectifiers. Arc welding transformers provide alternating current and are widely used. DC arc welding generators provide direct current, are more complex to manufacture, consume more materials, and are less efficient. They have a tendency to be gradually replaced by arc welding rectifiers. The arc welding rectifier is a DC arc welding power source developed in the 1950s. It uses silicon diodes or silicon controlled rectifiers as the rectifier.
The transistor arc welding power supply composed of high-power transistors that appeared in the 1960s can achieve higher control accuracy and excellent performance, but the cost is higher. The simplest of the welding energy equipment for resistance welding is the resistance welding transformer, with a no-load voltage range of 1 to 36 volts and a current from several thousand to tens of thousands of amps. The welding machine equipped with this kind of welding energy equipment is called an AC resistance welding machine. Others include low-frequency resistance welding machines, DC pulse resistance welding machines, capacitor energy storage resistance welding machines and secondary rectification resistance welding machines
2. The function of the welding head is to convert the energy output from the welding energy equipment. It is converted into welding heat, and the welding material is continuously fed, while the machine head itself moves forward to achieve welding. The welding tongs used for manual arc welding must continuously feed the welding rod downwards manually as the welding rod melts, and move forward to form a weld.
The automatic welding machine has a mechanism for automatically feeding the welding wire, and a machine head traveling mechanism to move the machine head forward.
There are two commonly used types: trolley type and hanging type. The welding head of resistance spot welding and projection welding is the electrode and its pressurizing mechanism, which is used to apply pressure and energize the workpiece. Seam welding also has a transmission mechanism to drive the workpiece to move. Butt welding requires static and dynamic fixtures and fixture clamping mechanisms, as well as movable fixtures and upsetting mechanisms.
3. The function of the welding control system is to control the entire welding process, including controlling the welding procedures and welding specification parameters. General AC arc welding machines do not have a control system. High-efficiency or precision welding machines are controlled by electronic circuits, digital circuits and microprocessors.
Components of automated welding equipment 1. Welding power source, its output power and welding characteristics should match the proposed welding process method, and be equipped with an interface connected to the main controller.
2. Wire feeder and its control and speed regulation system. For wire feeders with higher requirements for wire feed speed control accuracy, the control circuit should add speed measurement feedback
3. Use it to move the welding head The mechanism, which consists of a welding head, a welding head support frame, a hanging carriage, etc., is based on the precision welding head mechanism, and its drive system should use a servo motor equipped with an encoder
4. Weldment movement or displacement mechanism, such as welding roller frame, head and tail frame turning machine, rotary platform and positioner, etc. Precision mobile displacement mechanism should be driven by servo motor
5. Weldment Clamping mechanism.
6. The main controller, also known as the system controller, is mainly used for the linkage control of each component, the control of the welding program, and the setting, adjustment and display of the main welding parameters. Control functions such as fault diagnosis and human-machine dialogue can be expanded when necessary.
7. Computer software. Computer software commonly used in welding equipment includes: programming software, functional software, process method software and expert systems, etc.
8. Welding head guidance or tracking mechanism, Arc voltage automatic controller, welding gun oscillating device and monitoring system
9. Auxiliary devices, such as wire feeding system, circulating water cooling system, flux recovery and conveying device, wire holder, cable hose and drag chain structure Design three parts of electrical control design.
10. Welding robot, also known as mechanical arm, is an important part of automated welding equipment. Its main tasks include: welding, cutting, thermal spraying, handling, etc.