A gas-shielded welding machine is an efficient welding device that uses gas to shield the arc, fusing the welding wire and the workpiece, enabling the connection of various metal materials. Gas-shielded welding machines have numerous advantages, such as fast welding speed, high weld quality, minimal deformation, and strong adaptability. However, they are not without their flaws. During use, various malfunctions can occur, affecting welding quality and efficiency, and potentially causing safety issues. What are the common malfunctions of gas-shielded welding machines, and how should they be addressed? This article will provide a detailed introduction, aiming to help you solve problems encountered during welding and improve your welding skills and expertise.

I. Common Malfunctions of Gas-Shielded Welding Machines

The common malfunctions of gas shielded welding machines can be categorized as follows:

1. Mechanical Failures: These are mainly characterized by unstable wire feeding, wire blockage, unstable arc, poor weld formation, and excessive spark splatter. The causes of mechanical failures include wear, contamination, or damage to components such as the wire feed roller, wire feed hose, contact tip, and welding gun.

2. Electrical Failures: These are mainly characterized by the welding machine not starting, not feeding the wire, not igniting, and not adjusting the current and voltage phenomenon. The main causes of circuit failure are power lines, fuses, switches, connectors, control boards and other parts of the open circuit, short circuits, poor contact, and so on.

3. Gas Flow Failures: These are mainly characterized by insufficient gas flow, impure gas, continuous gas flow, or gas leakage. Causes of gas flow failures include blockages, damage, or faults in components such as the gas cylinder, pressure regulator, heater, solenoid valve, gas hose, and diverter.

4. Process Failures: These are mainly characterized by defects in the weld seam, such as pores, cracks, lack of fusion, slag inclusion, and oxide scales. Process failures are often due to the inappropriate selection or control of welding materials, parameters, methods, and environment.

II. Troubleshooting Methods for Gas-Shielded Welding Machines

To address the common malfunctions of gas-shielded welding machines, the following methods can be adopted:

1） Mechanical Failure Solutions:

1. Check if the wire feed roller matches the wire diameter, is free of iron powder or oil stains, and is not worn or slipping. Ensure the correct pressure and rotation direction. Clean or replace if necessary.

2. Check if the wire feed hose matches the wire diameter, is free of dust or iron filings, and is not damaged or blocked. Ensure the correct length. Clean or replace if necessary.

3. Check if the contact tip matches the wire diameter, is not worn or oversized, and is clean or coated with anti-spatter spray. Clean or replace if necessary.

4. Check if the welding gun is damaged or has a short circuit, is set at the correct angle and extension length, and if the sheath is cleaned or replaced. Repair or replace if necessary.

2） Electrical Failure Solutions:

1. Check if the power line is broken or shorted, is properly grounded, and has the correct voltage and phase sequence. Repair or replace if necessary.

2. Check if the fuse is blown and if it has the correct specifications and model. Replace if necessary.

3. Check if the switch is damaged or stuck and if it is in the correct position. Repair or replace if necessary.

4. Check if connectors are loose or have poor contact, if they are properly inserted and locked, and if they are cleaned or tightened. Address as needed.

5. Check if the control board is damaged or faulty, if it has the correct parameters and display, and replace or repair if necessary. Contact the manufacturer if needed.

3） Gas Flow Failure Solutions:

1. Check if the gas cylinder has sufficient pressure and capacity, is properly installed and placed, and is regularly inspected and replaced. Address issues promptly.

2. Check if the pressure regulator has the correct output pressure and flow rate, and if it is damaged or blocked. Clean or replace if necessary.

3. Check if the heater is working normally and at the correct temperature, and if it is damaged or frosted. Clean or replace if necessary.

4. Check if the solenoid valve operates and controls correctly, and if it is damaged or leaking. Clean or replace if necessary.

5. Check if the gas hose is damaged or leaking, if it is properly connected and sealed, and if it is cleaned or replaced. Address as needed.

6. Check if the gas hose is damaged or leaking, if it distributes and flows correctly, and if it is cleaned or replaced. Address issues promptly.

4） Process Failure Solutions:

1. Check if the welding material matches the base material, has the correct composition and diameter, is clean and dry, and is stored and used properly. Replace or treat as necessary.

2. Check if the welding parameters meet the requirements and have the correct current and voltage, wire feed speed, and gas flow rate, and if they are adjusted and matched appropriately. Adjust or replace as needed. How to Adjust the Current and Voltage of MIG Welding? 2 Methods for Precise and Fast Adjustment!
   

3. Check if the welding method suits the welding position and shape, if the welding posture and direction are correct, if the welding method and sequence are proper, and if the welding speed and swing amplitude are appropriate. Adjust or learn as necessary.

4. Check if the welding environment is conducive to welding, if it is clean and ventilated, if it avoids and isolates fire sources and flammable materials, and if wind speed and humidity are controlled and eliminated. Address issues promptly or relocate.

A gas-shielded welding machine is an efficient, high-quality welding equipment, but various malfunctions can arise during its use, affecting welding quality and safety. Therefore, welders should master the techniques of using CO2-shielded welding, understand the common malfunctions and their solutions, and promptly identify and resolve issues to ensure welding quality and production efficiency. This article introduced four types of malfunctions- mechanical, electrical, gas flow, and process failures, and their corresponding solutions, hoping to be helpful. Additionally, it reminds users to follow welding procedures, prepare adequately before welding, check all parts of the welding machine, select appropriate parameters and materials, prevent malfunctions, and improve welding quality and safety.

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3. 11 Types of Arc Welding: Applications & Benefits

4. Choosing the Right Shielding Gases for Arc Welding

5. Overhead Arc Welding: A Practical Guide