The statement that the weld produced by gas shielded welding is not as solid as that of arc welding is not universally true. There are two types of welding wires used in gas shielded welding: solid and flux cored.
The common welding technique for solid welding wire is push welding, which results in shallower weld penetration compared to handle welding.
On the other hand, the general welding method for flux cored welding wire is pull welding, similar to handle welding. The quality of welds produced using this method is comparable to that of handle welding.
In fact, many large equipment and tools, such as shipyards, are now primarily welded using gas shielded flux cored wire.
Manual arc welding vs CO2 gas shielded welding
CO2 gas shielded welding:
Advantages of Carbon Dioxide Gas Welding:
- Carbon dioxide gas provides good weld formation, has a fast welding speed, and eliminates the need to change welding rods, saving time and increasing efficiency.
- Carbon dioxide gas is an economical and cost-effective option.
- The automatic control of the mechanical method is used to feed the welding wire and control the movement of the welding gun, which contributes to enhancing welding quality and productivity.
- This method is well-suited for workshop production and is convenient for use in areas where on-site conditions are difficult, such as with poor wind resistance and the need for CO2 gas protection.
Disadvantages of Carbon Dioxide Gas Welding:
- CO2 gas shielded welding has a tendency to produce a large amount of spatter. During the welding process, the decomposition of CO2 gas generates carbon, leading to an increase in carbon content in the weld and increasing the likelihood of defects such as porosity.
- CO2 gas shielded welding requires special attention to safety due to the high current density, high arc temperature, and stronger arc radiation compared to manual arc welding. This can cause eye injury and skin burns.
- This method of welding also produces smoke, metal dust, and harmful gases such as CO and NO3.
- The workpiece has strict requirements for groove and assembly clearance, and the selection of welding specifications is also stringent.
Advantages of Manual Arc Welding:
- The manual welding process is protected by a coating that contains de-carburizing elements, which reduces the amount of carbon in the weld.
- Arc welding is easy to manage, as it contains slag.
- It is convenient, flexible and the most economical choice for multi-variety and small batch welding.
- Manual arc welding cannot be replaced by other welding methods for many installation and repair welding applications.
Disadvantage of Manual Arc Welding:
- The quality of manual arc welding is heavily dependent on the skill level of the welder, requiring strict training for welders before they can engage in this type of welding work.
After investigation, it was discovered that there is no clear division of labor between manual arc welding and CO2 gas shielded welding in the workshop, as both welding machines can meet production requirements. However, manual arc welding has the advantage of being easily portable and having good mobility and flexibility.