What is a Welding Machine?
A welding machine is a professional power tool that provides the energy and motion to join two or more parts together made of metals or thermoplastics, including wire & torch motion and control system.
You will meet many types of welder machines in the market for metal fabrication. It is difficult to choose a suitable welding machine for your business. We have listed 12 most common welders for your reference.
Laser welder is a smart welding system used to join metal parts with laser beam. It uses the high heat conduction of laser beam to diffuse into the metal, and melts the metal to form a specific molten pool to achieve the purpose of welding. The weldable graphics include points, lines, circles, squares or all drawings by AutoCAD software.
Laser welder uses a laser beam as a heat source. It can deposit, seal and fill the repair functions for the wear, scratches, pinholes, cracks, defect deformation, hardness reduction, sand holes and other defects of metal molds and parts. It can perform precise welding on some thin-walled materials and parts, and realize spot, butt, stitch, and sealing welding.
Laser welding machine is a new type of welding tool with high speed, small heat-affected zone, high positioning accuracy, smooth welding seam. With a handheld laser welding gun, it will be assembled as a portable laser welder, which is easy to move. With a CNC controller, it will be built as an automatic laser welder to finish the welding job without human intervention. With a robotic arm, it will be made as a laser welding robot for 2D/3D welding projects and plans.
Plasma welder is a type of professional easy-to-use welding machine that utilizes a transferred arc between the tungsten electrode and the metal part or a non-transferred arc between the tungsten electrode and the nozzle. Use the plasma gas sprayed from the welding torch for protection, and supplement an auxiliary shielding gas around it.
Plasma welding uses a plasma arc as the heat source. The ordinary tungsten arc becomes a plasma arc with high energy density and high temperature through the special compression effect of the plasma arc torch, and the arc stability is also high. When it is used as the heat source, it has strong penetration ability and high speed. The heat-affected zone is small and the welding current adjustable range is large, so it is a method with wide applicability.
Plasma arc welding is used for welded pipe manufacturing, small size welding on thin plate components and equipment, pipe root and thin-walled pipe welding. It is also used in some applications of electron beam welding, which has the advantage of welding in the atmosphere with much lower equipment costs compared to electron beam welding.
TIG welder is a portable welding tool that adopts the high-voltage breakdown arc starting method for welding. TIG welding refers to tungsten inert gas shielded arc welding, which uses industrial tungsten or active tungsten as non-melting electrodes and inert gas (argon) as protection, referred to as TIG. TIG welding is suitable for non-ferrous metals and alloy steels that are easily oxidized (Al, Mg, Ti and their alloys and stainless steel). It is suitable for single-sided welding and double-sided forming, such as bottom and pipe welding. It is also suitable for thin sheet metal.
TIG welding technology is based on the principle of ordinary arc welding, using argon gas to protect the metal material, and through high current, the material is melted into a liquid state on the substrate to be welded to form a molten pool, so that the metal to be welded and the material are formed. It is a welding technology in which the metallurgical combination of materials is achieved. Due to the continuous supply of argon gas during high-temperature fusion welding, the welding material cannot be contacted with oxygen in the air, thereby preventing the oxidation of the material.
MIG welder is a high-speed arc welding machine that uses a melting electrode and an external gas as an arc medium, and protects weld pools, metal droplets, and high-temperature in the heat affected zone (HAZ). MIG is the English acronym for Metal Inert Gas. The inert gas (Ar or He) shielded arc welding method with solid wire is called molten electrode inert gas shielded welding, or MIG welding for short. In this method, the tungsten electrode in the torch is replaced by a wire. Others are the same as TIG welding. Therefore, the wire is melted by the arc and fed into the welding zone. Electrically driven rollers feed the wire from the spool to the torch as needed for welding. The heat source is also a DC arc, but the polarity is reversed from that used in TIG welding. The protective gas used is also different. 1% oxygen should be added to argon to improve the stability of the arc.
Like TIG welding, it can weld almost all metals, especially suitable for aluminum and aluminum alloys, copper and copper alloys, and stainless steel. There is almost no oxidation burning loss during the welding process, only a small amount of evaporation loss, and the metallurgical process is relatively simple.
AC welder uses alternating current through a special step-down transformer inside the machine and then outputs low-voltage and high-current electric energy for welding. It has the advantages of simple structure, convenient maintenance, no magnetic deviation during welding, and is widely used. Using ordinary electrodes, stainless steel electrodes, cast iron electrodes, and high-power welding machines can barely use 506 electrodes. There are also a wide range of base metals that can be welded (only special materials such as gold, silver, copper, and tin cannot be welded)
DC welder performs welding by converting alternating current into direct current through a rectifier converter. It has the advantages of small size and light weight. Its structure is relatively complex, and maintenance is difficult. However, its performance can completely replace the AC welder, and the DC welding machine is more widely used. Including special materials and special electrodes can be welded.
CO2 Gas Shielded Welding Machine
Carbon dioxide gas shielded welding machine, referred to as CO2 welder, is an advanced fusion welding system that uses the carbon dioxide gas ejected from the nozzle as a protective gas to isolate the air and protect the molten pool. Simple operation in application, suitable for automatic welding and omnidirectional welding. You must pay attention to the working environment and gas protection during working, which is suitable for indoor operations. The input voltage of low-power CO2 gas shielded welder machine is generally 220V AC, and high-power uses 380V AC power. The output voltage is generally 12--36V. It is mainly used for low-carbon steel, low-alloy high-strength steel, high productivity, and can be used for thin plate and medium-thick sheet metal welding.
Butt welder is a type of resistance welding machine, which uses the resistance heat and a large amount of plastic deformation energy of the welding zone itself to make the two separated metal atoms close to the lattice distance to form metal bonds, and generate a sufficient amount of joint on the joint surface. grains to obtain solder joints, welds or butt joints. It is a connection method with stable quality, high production efficiency, and easy realization of mechanization and automation.
Butt welding machine uses the resistance between the contact surfaces of the two parts to instantly pass a low voltage and a large current to make the contact surfaces of the two butt-jointed metals instantly heat to melt and fuse. Butt welding machine is divided into flash butt, steel butt and copper rod butt welding machine according to different methods.
It can join various metal sheets, pipes, bars, profiles, solid parts and knives, and can weld non-ferrous metals and alloys such as low carbon steel, high carbon steel, alloy steel, stainless steel. It is widely used in automobiles, aerospace, electronics, and household appliances.
Flash butt welding machine is a welder used for longitudinal connection of steel bars and prestressed steel bars and screw end rods. The principle of flash butt welding of steel bars is to use a butt welding machine to make the steel bars at both ends contact, and through a low-voltage strong current, after the steel bars are heated to a certain temperature and become soft, axial pressure upsetting is performed to form a butt welded joint.
Flash butt welding can be divided into continuous and preheated flash butt welding. Continuous flash butt welding consists of flash stage and upset stage. Preheat flash butt welding simply adds a preheat stage before the flash stage. Flash butt welding uses the heat generated by the contact resistance to heat the metal part, the metal surface is melted, the temperature gradient is large, and the heat affected zone is relatively small. The weld is formed under the condition of plastic deformation of the counterpart solid phase metal of the part to form a common grain. The weld structure and composition are close to the base metal (or after heat treatment), and it is relatively easy to obtain equal-strength and equal-plastic welded joints. The flashing process has the self-protection function of exhausting air and reducing metal oxidation. Upset forging can also drain oxides out of the weld with the liquid metal. Weld inclusions, incomplete penetration and other defects are less. The flashing process has a strong self-adjustment function, and has low requirements for strictly maintaining the specification and consistency, and the welding quality is stable. The electric power required per unit of welding cross-sectional area is small, and only (0.1-0.3) KVA/mm2 electric power is required for low carbon steel.
Spot welder is a resistance welding machine that assembles the weldment into lap joints and presses it between two cylindrical electrodes, and uses resistance heat to melt the base metal metal to form a solder joint. The spot welder machine uses the high-temperature arc generated when the positive and negative poles are short-circuited instantaneously to melt the material to be welded between the electrodes to achieve the purpose of combining them. The main component of the electric welding machine is a step-down transformer. The two ends of the secondary coil are the welded metal part and the welding rod. When working, the arc is ignited, and the rod is fused into the gap of the metal part at the high temperature of the arc.
Spot welding machine is used for repairing holes of gold and silver jewelry, spot welding blisters, repairing seams and inlaid parts. It can also be used for false filling of blisters and micro-precision parts such as integrated circuit leads, battery nickel strips, picture tubes, electron gun assembly, and watch hairsprings. The heat-affected zone in the process is small, the size of the nickel spot can be adjusted at will, and the solder joints are fine, flat, and beautiful, without excessive post-weld treatment, and can be accurately positioned. The spot welding speed is fast, the quality is high, and the solder joints are pollution-free and efficient. It is suitable for various metals such as gold, silver, platinum, stainless steel, titanium and their alloys.
SAW Welder (Submerged Arc Welding Machine)
SAW welder is also known as submerged arc welder machine, which is a type of melting electrode electric welding machine with granular flux as the protective medium, and the arc is hidden under the flux layer. Firstly, enough granular flux is evenly deposited on the welding seam of the weldment, then the contact tip and the weldment are respectively connected to two stages of the welding power source to generate the arc, and finally the welding wire is automatically fed and the arc is moved for welding. Submerged arc welder can weld carbon structural steel, low alloy structural steel, stainless steel, heat-resistant steel, nickel-based alloy, and copper alloy.
High weld quality, good slag isolation and air protection, the main component of the arc area is CO2, the nitrogen content and oxygen content in the weld metal are greatly reduced, the welding parameters are automatically adjusted, the arc travel is mechanized, the molten pool exists for a long time, and the metallurgical reaction sufficient and strong wind resistance, so the weld composition is stable and the mechanical properties are good. The slag isolates the arc light for the benefit of welding operations. Mechanized walking, low labor intensity.
Due to the limitation of welding position, due to the reason of flux retention, if special measures are not taken, submerged arc welding is mainly used for seam welding in horizontal and downward position, but cannot be used for horizontal, vertical and overhead welding. Due to the limitation of welding materials, it is not possible to weld aluminum, titanium and other highly oxidizing metals and their alloys.
High Frequency Welding Machine
High frequency welding machine is different from other welders, its function and purpose are not just single welding. The heating speed is fast and the efficiency is high. It can instantly melt any metal object. High frequency welder can not only be used to weld various metal materials, but also for diathermy, smelting, heat treatment and other processes. It is suitable for heat treatment quenching, annealing, metal diathermy forging, extrusion forming, and solder welding. Since the whole machine weighs only a few kilograms and is small in size, it does not require acetylene cylinders or oxygen cylinders, so it is easy to carry and is very suitable for outdoor or harsh environments.
Pressure Welding Machine
Pressure welding machine is a type of welder table with a floating device, so that the pressure does not directly act on the turntable, so as to achieve the precise positioning of the hot pressure welding and realize the precise welding. The pressure welder adopts a positioning device on the floating device. When working, the pressure welder can overcome the position deviation caused by the use of the floating device, so that the template and the head fastened to the floating plate do not move back and forth, left and right. A certain vertical pressure is applied to the upper end of the knife, and under the combined action of these two forces, the aluminum wire under the riving knife is regularly creeping through the control of time. In order to obtain high tensile strength points, the best conditions must be selected, which depends on factors such as ultrasonic vibration power, pressure and ultrasonic vibration time. In order to obtain the welding point with high tensile strength, the best conditions must be selected, which depends on factors such as ultrasonic vibration power, pressure and ultrasonic vibration time. The three should be matched with each other to adjust the best point.
Pros & Cons
Electric welding machines use electric energy to instantly convert electric energy into heat energy. Electricity is very common. Electric welding machines are suitable for working in dry environments and do not require too many requirements. Because of their small size, simple operation, convenient use, and high speed, strong seam and other advantages, they are widely used in various fields, especially for parts that require high strength. After heat treatment, it has the same strength as the base metal, and the sealing is very good, which solves the problems of sealing and strength for the manufacture of storage gas and liquid containers.
During the use of the electric welding machine, a certain magnetic field will be generated around the machine. When the arc burns, it will generate radiation to the surrounding. There are infrared, ultraviolet and other light species in the arc, as well as metal vapor and smoke and other harmful substances, so the operation must be Take adequate protective measures. Welding is not suitable for high carbon steel. Due to the crystallization, segregation and oxidation of the weld metal, the performance of high carbon steel is poor, and it is easy to crack after welding, resulting in hot and cold cracks. Low carbon steel has good performance, but it needs to be handled properly in the process, and the cleaning of rust is cumbersome. Sometimes there will be defects such as slag inclusion, cracks, stomata and undercuts in the weld, but proper operation will reduce the occurrence of defects.
Things To Consider
After reading this article, do you feel familiar with the welding machine? Whether a beginner or a professional welder, you should know how to choose the right welder.
What is Welding?
Welding is a method of making metal connections. It uses heating means to form a permanent and firm bond between the two metals through the mutual diffusion of atoms or molecules of the welding material on the contact surface of the two metals. The joints formed by connecting by welding are called solder joints.
What is Solder?
Solder is a fusible metal with low melting point, high mechanical strength, low surface tension and strong oxidation resistance. The solder used for hand soldering is a tin-lead alloy.
What is Flux?
Flux is a material that removes oxides, sulfides, oils and other contaminants from the metal surface and prevents the solder from continuing to oxidize during heating. It also has the characteristics of enhancing the activity of solder and metal surfaces and increasing wetting. The flux generally uses super rosin as the matrix material, and adds a certain activator such as diethylamine hydrochloride.
What is Solder Mask?
Solder mask (solder resist) is a high temperature resistant coating that protects the parts of the printed circuit board that do not need soldering. The types of solder resist include thermal curing solder resist, ultraviolet light curing solder resist (photosensitive solder resist), and electronic radiation curing solder resist.
What is Solder Wire?
Solder wire is a solder used for manual soldering, which is made of flux and solder, and a solid flux is entrained in the solder tube. Different tin and lead components have different melting points. Commonly used solder wires are Sn63Pb37 with a melting point of 183°C and Sn62Pb36Ag2 with a melting point of 179°C. Solder wire is tubular. The diameter of the tubular solder wire is 0.2, 0.3, 0.4, 0.5, 0.6, 0.8, 1.0 and other specifications. Solder wire of 0.5 and 0.6 can be used for welding perforated components.
What is Arc Spot Welding?
Arc spot welding is a welding method that uses thin plate lap joints, TIG/MIG/MAG/CO2 welding, and a certain welding current to form a surface nugget and connect the upper and lower plates within a set time.
How to Weld at Home for a Beginner?
The most common arc welding machine should not work at home, because the current required for arc welding is less than tens of amps, and your protector will jump, so TIG, MIG, MAG can be excluded. Resistance welding and thermocompression welding are too large for home use. The disadvantage of oxyacetylene gas welding is that the flame temperature is 3000+. If you are not careful, your home will be set on fire. The most reliable way to weld at home is brazing. Brazing requires high-frequency heating, and soft brazing is more suitable. However, you also need to consider what you are soldering, because the metal bonding strength is not high with this way. Laser welding, plasma welding, and electron beam welding are a bit expensive, but they can be used at home, and the welding quality is good and the speed is fast.