(1) Spot welding: The weldment is pressed between the two cylindrical electrodes, heated by electricity, so that the weldment melts at the contact to form a nugget, and then the power is cut off, and it solidifies and crystallizes under pressure to form a dense solder joint.
Spot welding is suitable for welding thin plates (laps) and steel bars below 4 mm, and is widely used in the production of automobiles, aircraft, electronics, instruments and daily necessities.
(2) Seam welding: Seam welding is similar to spot welding, except that a rotating disc electrode is used instead of a cylindrical electrode. The superimposed workpieces are pressurized and energized between the discs and fed in with the rotation of the discs to form a continuous weld.
Seam welding is suitable for welding thin plate lap joints with a thickness of less than 3 mm, and is mainly used in the production of hermetically sealed containers and pipes.
(3) Butt welding: According to the different welding processes, butt welding can be divided into resistance butt welding and flash butt welding.
1) Resistance butt welding The welding process is to first apply the top forging pressure (10-15 MPa) to make the workpiece joint close contact, energized and heated to a plastic state, and then apply the top forging pressure (30-50 MPa), and at the same time cut off the power, so that the weldment contact is welded under pressure to produce plastic deformation.
Resistance butt welding is easy to operate, and the joint shape is smooth, but the requirements for processing and cleaning the end face of the weldment are high, otherwise it will cause uneven heating of the contact surface, produce defects such as oxide inclusion, and impermeable welding, and affect the welding quality. Therefore, resistance butt welding is generally only used for welding workpieces with a diameter of less than 20 mm, a simple cross-section, and a small force.
2) flash butt welding welding process is to first energize, and then make the two weldments slightly contact, due to the uneven surface of the weldment, so that the current density of the contact point through is very large, the metal quickly melts, gases, blasts, splashes out of sparks, resulting in flash phenomenon. Continue to move the weldment, produce new contact points, flash phenomenon continues to occur, when the end face of the two weldments is all melted, quickly pressurized, then the power is cut off and continue to pressurize, so that the weldment is welded.
The joint quality of flash butt welding is good, and the pre-welding cleaning of the joint surface is not high. It is often used to weld important workpieces with large forces. Flash butt welding can not only weld the same metal, but also weld dissimilar metals such as aluminum steel, aluminum and copper, and can weld 0.01 mm wire, 500 mm diameter pipes and 20 000 mm2 plates.
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Megmeet inverter - maintenance precautions and items for high-voltage inverters
Precautions for maintenance of high-voltage inverters
1. Carefully monitor and record the display parameters on the man-machine interface of the inverter, and reflect the abnormality immediately
2. Carefully monitor and record the ambient temperature of the inverter room, and the ambient temperature should be between -5 °C and 40 °C. Phase-shifting transformers ...
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Megmeet Welders – What are the commonly used types of welders?
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Communication welders and DC welders should ...
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Megmeet PLC - What are the functions of the PLC gateway?
1. PLC industrial gateway has rich interfaces and is easy to deploy
It supports 4G, 3G, PPPOE, Wi-Fi network, digital IO input and output, and serial terminal communication, providing different access solutions for different applications.
2. Intelligent analysis and efficient access
Inline protocol analysis ...
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1. PLC is a relatively mature control system composed of single-chip microcomputer, which is the product of a mature and stable single-chip microcomputer application system that has been debugged. It is highly versatile.
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Megmeet drives – a common fault in low-voltage drives
External electromagnetic interference can easily cause malfunctions
If there are interference sources around the inverter, they will invade the inside of the inverter through radiation or power lines, causing the control loop to malfunction, causing abnormal operation or shutdown, and even damage to the inverter in severe cases. Noise suppression on the outside ...
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Features of Megmeet CO2/MAG all-digital heavy-duty welder
1. The arc is stable in the field of full current, the spatter is small, and the same welding machine is not only suitable for small current base welding, but also suitable for high current and high deposition rate work
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Megmeet inverter – the difference between voltage type inverter and current type inverter
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Megmeet PLC – 10 PLCs integrated failure analysis
1. Grounding problems
The grounding requirements of the PLC system are relatively strict, and it is best to have an independent dedicated grounding system, and it should also be noted that other equipment related to PLC should also be reliably grounded.
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Megmeet drives – the replacement steps for high-voltage drive power units
1) Shut down, so that the inverter out of the operating state;
2) Cut off the high-voltage power supply and push out the high-voltage cabinet trolley (when there is a bypass cabinet. The inverter can be isolated by the disconnecting switch of the bypass cabinet), the local or remote high-voltage disconnect switch can be locked, and the high-voltage cabinet grounding switch can be grounded;
3) Hit ...
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Megmeet Inverter - Precautions for the Use of Inverter (1-10)
1. The inverter must be selected correctly.
2. Read the product manual carefully, and wiring, installation and use in accordance with the requirements of the manual.
3. The inverter device should be reliably grounded, and the radio frequency interference should be suppressed to prevent the inverter from causing electric shock due to leakage.
4、 ...
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Megmeet servo drive - common faults and treatment methods of servo drives
1. The motor runs differently in both directions
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2. The motor speed is abnormal
Cause of failure ...
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Megmeet inverter - what are the control methods of the inverter?
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Megmeet inverter – three ways to connect the PLC to the inverter
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Solutions to common faults of Megmeet inverter (2)
Fault three
Fault phenomenon: There is a rebound phenomenon when the rotation starts
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2. Appropriately reduce the stator resistance (P03.07) and no-load current value (P03.11 ...
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Megmeet inverter – the basic principle and application of high-voltage inverter
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Three-phase high-voltage electricity enters the high...
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Safety operation procedures for spot welding machines:
1. Before operation, the oil stain of the upper and lower electrodes should be removed. After power-on, the body shell should be free of leakage.
2. Before starting, the steering switch of the control line and the small switch of welding current should be connected, the number of poles should be adjusted, and then the water source and gas source should be connected.
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Maintenance inspection of Megmeet inverters
1. The Megmeet rectifier module is damaged
It is usually caused by grid voltage or internal short circuit. In the case of sweeping the internal short circuit, the rectifier bridge is replaced. When dealing with faults on site, we should focus on checking the status of the user's power grid.
Such as the power grid voltage, whether there is an electric welding machine, etc.
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Megmeet PLC - the hardware composition of PLC control
1. Power components
The power supply assembly is used to provide the power required for the operation of the PLC, and the external power supply can be converted into a power supply for the PLC internal and applicable to the case.
2. Microprocessor CPU and memory components
Microprocessor CPU is the core device of PLC, and CPU is different from each manufacturer.
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