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DC Spot Welding Machine

DC welding is a type of welding that uses direct current to create an electrical arc between the welding electrode and the metal being welded. The electrical current flows in one direction, from the negative electrode to the positive metal workpiece.

Benefits of DC Spot Welding Machine

High stability
The DC welding machine has high current stability and excellent arc stability. During the welding process, the welding quality is less affected by external factors. Therefore, the DC welding machine is very suitable for use in occasions where high quality welds are required.

High thermal efficiency
Due to the relatively stable output current of the DC welding machine, the thermal efficiency is higher than that of the AC welding machine. This means that at the same voltage, the DC welding machine can weld larger workpieces than the AC welding machine.

Easy operation
The DC welding machine is easy to operate and requires relatively basic welding skills, so it is easy to learn. In addition, the high stability of DC welding also makes the operation more stable and reliable.

Wide range of applications
DC welding machines are widely used in various welding occasions because of their easy operation and stable quality. For example, welding in various industries and fields such as ships, automobiles, power stations, and pipelines.

Why Choose Us

01/

Competitive prices
We offer our products at competitive prices, making them affordable for our customers. We believe that high-quality products should not come at a premium, and we strive to make our products accessible to all.

02/

Rich experience
Has a long-standing reputation in the industry, which makes it stand out from its competitors. With over many years of experience, they have developed the skills necessary to meet their clients' needs.

03/

Quality assurance
In terms of quality assurance, the company strictly follows the standards and norms of the industry quality system. Adopt industry-leading testing equipment to ensure product quality and good reputation.

04/

High quality products
We always put customer needs and expectations in the first place, refine on, continuous improvement, to seek every opportunity to do better, to provide customers with their expectations of quality products, to provide customers with the most satisfactory service at anytime.

05/

Advanced equipment
We take strong measures to ensure that we use the highest quality equipment in the industry and that our equipment is regularly and meticulously maintained.

06/

Professional team
We have a team of skilled and experienced professionals who are well-versed in the latest technology and industry standards. Our team is dedicated to ensuring that our customers get the best service and support possible.

Classification of DC Welding Machines

Industrial frequency AC welding machine
The industrial frequency AC welding machine is a traditional welding equipment. Its working principle is to reduce the voltage of AC through a transformer, then convert AC into DC through a rectifier, and finally heat the workpiece through the electrode to achieve welding. The industrial frequency AC welding machine has the advantages of simple structure, low cost, and easy maintenance, but the disadvantages are low efficiency, high energy consumption, and high noise.

Inverter DC welding machine
The inverter DC welding machine is a new type of welding equipment using inverter technology. Its working principle is to convert AC into high-frequency pulse current through an inverter, and then heat the workpiece through the electrode to achieve welding. The inverter DC welding machine has the advantages of high efficiency, low energy consumption, low noise, and small size, but the disadvantages are high cost and difficulty in maintenance.

Capacitor discharge DC welding machine
Capacitor discharge DC welding machine is a device that uses capacitors to store energy and achieves welding through discharge. Its working principle is to convert AC into DC through a rectifier, and then store energy through a capacitor. When welding is required, the capacitor heats the workpiece through a discharge tube to achieve welding. Capacitor discharge DC welding machine has the advantages of high efficiency, low energy consumption, and low noise, but the disadvantages are high cost and difficulty in maintenance.

Magnetic amplification DC welding machine
Magnetic amplification DC welding machine is a device that uses the principle of electromagnetic induction to achieve welding. Its working principle is to convert AC into DC through a rectifier, and then generate a magnetic field through an electromagnetic coil. When welding is required, the magnetic field acts on the workpiece through electromagnetic induction to achieve heating and welding. Magnetic amplification DC welding machine has the advantages of high efficiency, low energy consumption, and low noise, but the disadvantages are high cost and difficulty in maintenance.

What Are the Accessories for Spot Welding Machines

Press handle
The press handle is one of the most common accessories of the spot welder. It is a key component of the spot welder that controls pressure by transmitting air pressure or hydraulic pressure. When purchasing the press handle, you should pay attention to the handle material, connection method, load-bearing capacity, and anti-vibration and anti-slip aspects.

Electrode
The electrode is the component that transmits current in the spot welder. Common electrode materials include copper, tungsten, molybdenum alloy, etc. When purchasing, you need to choose according to factors such as the material to be welded, welding time, and electrode size.

Cable
The cable is the transmission medium for the output current of the spot welder. Its quality has a great impact on the quality of spot welding and the life of the equipment. Therefore, when purchasing the cable, you need to consider its conductivity, anti-breakage performance, and anti-aging performance.

Water-cooling fixture
Some spot welders need to use water cooling to cool down, so a water-cooling fixture is needed. Its function is to guide the water flow to the inside of the cooling electrode, which plays a role in cooling and preventing electrode failure. When purchasing, pay attention to the caliber and joint material of the water-cooling fixture.

Other accessories
Some common accessories of spot welding machines include electric control board, voltmeter, grounding clamp, low-voltage power supply, etc. According to different needs, you can choose the spot welding machine accessories that suit you.

Uses of DC Welding Machines

DC welding machines are widely used in home maintenance, construction and industrial manufacturing. In home maintenance, DC welding machines can be used to repair the connection or reinforcement of metal parts such as furniture, doors, windows and electrical appliances. In construction, DC welding machines can be used to weld steel structures, building materials, plumbing equipment, etc. In industrial manufacturing. DC welding machines can be used in the production process of automobile manufacturing, shipbuilding, machinery manufacturing and other industries to connect various metal parts.

DC welding machines also have important applications in pipeline engineering, oil and gas industry and power engineering. In pipeline engineering, DC welding machines can be used to weld important pipeline systems such as oil pipelines and natural gas pipelines to ensure the firmness and sealing of their connections. In the oil and gas industry, DC welding machines can be used for the maintenance and reinforcement of equipment such as oil chains and gas storage tanks. In power engineering, DC welding machines can be used for the connection and maintenance of high-voltage transmission lines and transformers to ensure the stability and safe operation of the power system.

DC welding machines are also used to manufacture and repair aviation, aerospace and military equipment. In the aerospace industry. DC welding machines can be used to weld metal parts of aerospace vehicles such as aircraft rockets and satellites to ensure their structural safety and reliability. In the military field, DC welding machines can be used to produce and repair military equipment such as military vehicles and weapons to meet the needs of war and national defense.

The application of DC welding machines also involves new energy fields, such as solar photovoltaic and wind power generation. In the field of solar photovoltaic, DC welding machines can be used in the manufacture of solar panels to connect different solar cells to form a complete solar cell group. In the field of wind power generation, DC welding machines can be used in the production and maintenance of wind turbines. Ensure that the connection of its wind blades is firm and stable.

DC welding machines are also widely used in fields such as automobile maintenance and electronic manufacturing. In automobile maintenance. DC welding machines can be used to weld the repair and reinforcement of automobile bodies. In electronic manufacturing, DC welding machines can be used to weld the assembly of electronic products, such as circuit boards, electronic components, etc.

What is the Working Principle of Spot Welding Machine

The AC spot welder adopts the principle of double-sided double-point overcurrent welding. When working, the two electrodes pressurize the workpiece so that the two layers of metal form a certain contact resistance under the pressure of the two electrodes, and the welding current flows from one electrode to the other. When electrodes are used, an instantaneous thermal fusion is formed at the two contact resistance points, and the welding current flows from the other electrode along the two workpieces to this electrode to form a loop without damaging the internal structure of the welded workpiece.

The process of spot welding is to open the cooling water; clean the surface of the weldment, and after the assembly is accurate, send it between the upper and lower electrodes, apply pressure to make it contact well; electrify the contact surface of the two workpieces to heat and partially melt, forming Nugget; maintain the pressure after the power is off, so that the nugget is cooled and solidified under pressure to form a solder joint; the pressure is removed, and the workpiece is taken out. Spot welding process parameters such as welding current, electrode pressure, energizing time and electrode working surface size have a significant impact on welding quality.

The spot welder uses the high temperature arc generated when the positive and negative poles are instantaneously short-circuited to melt the solder and the material to be welded on the electrode to achieve the purpose of combining them. The structure of the electric welding machine is very simple, it is a high-power transformer, which converts 220V AC into a low-voltage, high-current power supply, which can be DC or AC. The welding transformer has its own characteristics, that is, it has the characteristics of a sharp drop in voltage. After the electrode is ignited, the voltage drops, and the working voltage of the electric welding machine is adjusted. In addition to the primary 220/380 voltage conversion, the secondary coil also has a tapped voltage conversion. At the same time, there is also an adjustable iron core that is adjusted by an iron core. Electric welding machine is generally a high-power transformer, which is made by the principle of inductance. The inductance will produce a huge voltage change when it is switched on and off, and the high-voltage arc generated by the instantaneous short-circuit of the positive and negative poles is used to melt the solder on the electrode. To achieve the purpose of combining them.

Spot welding is a resistance welding method in which the weldment is assembled to connect the joint and pressed between two electrodes, and the base metal is melted by resistance heat to form a welding spot. Spot welding is mostly used for the connection of thin plates, such as aircraft skins, smoke pipes of aero engines, and car cab shells. The welding transformer of the spot welding machine is a spot welding electrical appliance, and its secondary has only one loop. The upper and lower electrodes and the electrode arms are used to conduct welding current and transmit power. Cooling water passes through transformers, electrodes and other parts to avoid heat generation. When welding, the cooling water should be passed first, and then the power switch should be turned on. The quality of the electrode directly affects the welding process, welding quality and productivity. Electrode materials are commonly made of red copper, cadmium bronze, chromium bronze, etc.; the shape of the electrode is various, mainly according to the shape of the weldment. When installing the electrodes, pay attention to keeping the upper and lower electrode surfaces parallel; the electrode planes should be kept clean, usually with emery cloth or files for trimming.

Electric Welding Machine Installation Steps

Site selection
The welding machine should be placed in a well-ventilated, dry, clean, water-free and rain-free place, and there should be a wire plug and a ground plug on the ground.
The selected power socket should be equipped with appropriate insurance and filters.

Wiring
Turn on the welding machine, use a multimeter to measure the voltage at the output end, and confirm that the voltage matches the welding object.
Plug the power cord into the power socket, and the three wires of the plug should be connected to the three wiring rods on the distribution board.
Connect the lead of the welding machine to the workpiece end.

Grounding
Determine the grounding position and keep the ground dry, clean, oil-free and dirt-free.
Insert the ground plug of the welding machine into the ground base, and then connect the ground base to the metal parts on the ground.
Use a multimeter to measure the grounding resistance. If the resistance does not meet the relevant national requirements, the grounding position should be reselected.

Trial operation
Put on the woven mask, put on welding gloves, turn on the power switch, and start hot operation.
Adjust the voltage and current according to actual needs until you are satisfied.
After finishing welding, turn off the switch and remove the power wire, workpiece end and ground wire.

How to Maintain the Spot Welding Machine

Cooling

During welding, cooling water is needed to cool down the electrodes, secondary circuits, transformers, thyristors, rectifiers and other power components, so as to keep the spot welder from being overheated and to ensure normal use. Therefore, it is necessary to frequently check whether each branch waterway is unobstructed and clear any blocked waterways in time.

Spot welding electrodes

The electrode is the part that directly acts on the workpiece during spot welding. It has good conductivity, hardness and a high softening temperature, but it will inevitably deform under continuous high-voltage impact and high temperature. Therefore, it is necessary to timely correct the thickness and cleanliness of the electrode end according to the actual welding parameters and number of welds, or replace the electrode directly in time.

The ground wire must be connected properly

In order to ensure the safe use of the spot welder, the ground wire must be used. The ground wire must be kept intact and connected to the ground to reduce resistance, making the operation safer and more normal.

Cleaning the welding machine

For the treatment of spot welding machine, the transformer and power components inside the machine body must be kept clean. It uses electricity to weld, so the safety of electricity use must be ensured; the mainboard in the control box must be frequently dusted to avoid metal dust accumulation and hidden dangers to the mainboard; the solenoid valve also needs to be cleaned and tested regularly, and the failure of the air valve will cause serious welding instability.
Another part that needs to be cleaned frequently is the secondary copper connection part, especially the surface cleanliness of the parts that are frequently disassembled and adjusted! Otherwise, the dirt and wear on the copper surface will increase the impedance of the secondary circuit, reduce the output of the welding current, reduce the welding capacity of the spot welding machine, and also affect the stability of the welding current.

Detection and calibration of welding controller

Especially for constant current controllers, it is necessary to regularly calibrate the welding current with authoritative third-party testing equipment, otherwise the original welding current setting will cause poor welding due to the deviation of the current.

Our Factory

Jiaxiao company develop and produce spot welder controller and spot welding machine since 1992, we're one of the biggest suppliers in China. Spot welders, MFDC welder, variable frequency AC welder, butt welders, seam welders, gun welders, 3 phase welders, micro welders, special application machines are offered here. Our products are widely used in electrical production, auto parts manufacturing, battery production, metal splicing and other fields. With advanced technology, excellent management philosophy, high-quality products, and constantly develop and grow, widely praised by the industry and users. Based on our professional engineer team, rich experience and latest technical, we specialize in fitting your welding requirements to the proper welding equipment.

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FAQ

Q: What is a DC welding machine?

A: DC welding is a type of welding that uses direct current to create an electrical arc between the welding electrode and the metal being welded. The electrical current flows in one direction, from the negative electrode to the positive metal workpiece.

Q: Is DC or AC better for spot welding?

A: IS DC OR MFDC BETTER OR PREFERRED OVER AC IN SPOT WELDING? The answer to this question depends upon the product being welding, the quality standard, power availability and equipment intended for the job. If this is to be a robot/automation operation MFDC may be the best choice. It will reduce the weld gun weight.

Q: How do I know if my welding machine is AC or DC?

A: Simply put, when you look at a welding machine and see a DC label, it means the machine has constant polarity. If it says AC, then the polarity will change and alternate directions up to 120 times per second.

Q: How do you train operators to use a spot welding machine safely and effectively?

A: Train operators properly, including verbal and written instructions, regarding the importance of keeping their hands away from the moving electrodes. Make sure the foot switch used for machine initiation has a top and side shroud installed to prevent accidental activation.

Q: What are the limitations of spot welding machine?

A: The limitations of Spot Welding process are: Limited to thin materials. Requires precise alignment of electrodes. Not suitable for welding dissimilar materials.

Q: What is the principle of spot welding machine?

A: Spot Welding machines use a method called resistance spot welding to join overlapping metals between two electrodes using electrical resistance. Squeezing the workpieces between the electrodes applies pressure, and the passage of welding current through the resistive metals generates heat.

Q: What is the methodology of spot welding machine?

A: Two electrodes press the two workpieces together mechanically and fix the parts to be welded. By supplying an electrical power, a current flows between the two electrodes. The workpieces represent a resistance for the flowing current. This causes the metal to heat locally sufficiently to liquefy.

Q: What are the main components of a spot welding machine?

A: The main components of a spot welding machine include a transformer, control unit, electrodes, and a timer. The transformer reduces the input voltage to the required level for welding, while the control unit regulates the current and time. The electrodes, typically made of copper alloys, deliver the electrical current to the workpieces, and the timer determines the duration of the weld.

Q: What safety precautions should be taken when using a spot welding machine?

A: Safety precautions when using a spot welding machine include wearing appropriate personal protective equipment (PPE), such as welding gloves, safety glasses, and a welding helmet. Additionally, operators should familiarize themselves with the machine's controls and emergency stop procedures. The work area should be well-ventilated to prevent the accumulation of smoke and fumes.

Q: What are the advantages of using a spot welding machine?

A: Spot welding machines offer several advantages, including high productivity, low cost per weld, and ease of automation. They are particularly suitable for joining thin metal sheets and can be used in various industries, such as automotive, appliance manufacturing, and sheet metal fabrication.

Q: What materials can be welded using a spot welding machine?

A: Spot welding machines are primarily designed for use with ferrous metals, such as steel and iron. However, they can also weld non-ferrous metals like aluminum and brass, although this may require specialized electrodes and settings.

Q: What factors affect the quality of a spot weld?

A: The quality of a spot weld depends on several factors, including the material type and thickness, electrode wear, current and time settings, and the clamping force. Proper maintenance and calibration of the spot welding machine are essential for achieving optimal weld quality.

Q: What are the applications of welding machine?

A: It is vital in various industrial applications, from manufacturing and construction to automotive and aerospace industries. Welding is significant in industrial settings because it allows for the fabrication and repair of metal structures and components, enabling the production of complex and durable products.

Q: How does the power output of the spot welding machine affect the weld quality?

A: The amount of energy is chosen to match the sheet's material properties, its thickness, and type of electrodes. Applying too little energy will not melt the metal or will make a poor weld. Applying too much energy will melt too much metal, eject molten material, and make a hole rather than a weld.

Q: What safety precautions should be taken when operating a spot welding machine?

A: Safety glasses must be worn at all times in work areas. Long and loose hair must be contained. Leather gloves must be worn when handling hot metal. Sturdy footwear must be worn at all times in work areas.

Q: How often should the spot welding machine be serviced and maintained?

A: Arrange for a technician to service the welding gun and liner assembly at least once a year. Inspect all of the electrical cables at least once a month for signs of wear, including cracks and breaks, immediately replacing any cables with excessively worn or damaged insulation.

Q: How does the electrode shape and size influence the spot welding process?

A: Spot welding is a process for joining metal sheets by directly applying opposing forces with electrodes with pointed tips. The form of the electrodes localized the current and the heat generation. Thus the electrode tip contact area usually define the weld nugget size.

Q: What are the factors to consider when choosing the right spot welding machine for a specific application?

A: The thickness and type of material are among the most critical factors in selecting a spot welder. This is because different materials and their thicknesses have unique electrical and thermal properties, which significantly influence the welding process.

Q: How does the cooling system of the spot welding machine affect its performance and longevity?

A: Importance: The cooling system in a spot welding machine is essential for dissipating the heat generated during the welding process. It prevents overheating of the electrodes and the transformer, which can lead to equipment damage and reduced weld quality.

Q: How does the control system of the spot welding machine ensure precise welding?

A: This procedure is typically carried out with the aid of a specialized welding machine that applies pressure to the sheets in order to keep them in place and control the flow of electricity via the resistance welding process. The current is applied under a controlled force through the electrodes.

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