Job Description (JD)
| Nama Program | OPERASI TEKNOLOGI KIMPALAN ARKA [C259-008-3:2025] |
|---|---|
| Kod CU | C259-008-3:2025-C06 |
| Competency | Core |
| Tajuk CU | Perform GMAW 1G, 2G, 3G, 4G, 5G and 6G butt welding (carbon steel) |
| Penerangan CU | Perform GMAW 1G, 2G, 3G, 4G, 5G and 6G butt welding (carbon steel) describes the competency in joining two pieces of metal end-to-end using a continuous solid wire electrode fed through a welding gun. This process is characterized by its efficiency and ability to produce high-quality welds. The welding technique utilizes a shielding gas, typically a carbon dioxide, to protect the weld pool from atmospheric contamination, minimizing oxidation and enhancing weld integrity. As an electric arc forms between the wire electrode and the base metal, both the wire and the edges of the base materials melt to create a weld pool that fuses the metals together. GMAW allows for precise control heat input and travel speed, enabling welders to achieve optimal penetration and produce clean weld beads. In the 1G the workpieces are oriented horizontally, allowing the welder to easily deposit the weld bead on the upper surface where the two pieces meet, which provides excellent visibility and control heat input for strong fusion. In the 2G the workpieces are positioned vertically, requiring the welder to apply the weld horizontally along the joint while skilfully managing the arc and heat flow to overcome the effects of gravity on the molten pool. The 3G involves the workpieces being vertical, with the weld applied uphill (vertical up), where careful management of the weld pool is crucial to prevent sagging, or downhill (vertical down), which may be faster but still necessitates attention for a consistent butt weld. In the 4G the welding is performed from beneath horizontal workpieces, demanding precise control to prevent the molten material from dripping or sagging, thus requiring significant skill to achieve good fusion. The 5G the pipe is positioned horizontally but fixed so it cannot be rotated. The welder must weld in multiple positions (bottom, sides, and top) as they move around the pipe, with the weld performed in an uphill (vertical up) direction, requiring versatile skills and precise control. Lastly, the 6G involves the pipe is positioned at a 45-degree angle and is fixed with the weld performed in an uphill (vertical up) direction. This position combines all the complexities of welding in multiple orientations (overhead, vertical, horizontal and flat). Welders in this position must demonstrate exceptional skill and control to produce a high-quality weld bead. The person who is competent in this CU should be able to carry out GMAW 1G plate butt welding, carry out GMAW 2G plate butt welding, carry out GMAW 3G plate butt welding, carry out GMAW 4G plate butt welding, carry out GMAW 5G pipe butt welding and carry out GMAW 6G pipe butt welding. The outcome of this CU is the creation of high-quality welds characterized by structural integrity and uniform, consistent weld beads across all positions. These welds adhere to industry standards and specifications, ensuring they are free from defects such as cracks and porosities. The weld metal produced demonstrates essential properties, including high tensile strength, good ductility, adequate hardness, and impact toughness, which are vital for the durability and reliability of the welded joints. Additionally, proper fusion and penetration are achieved, ensuring a strong bond with the base metal. The ability to perform these welds in various positions (flat, horizontal, vertical, overhead, and inclined) demonstrates the welder's versatility and proficiency, enabling them to handle a wide range of welding scenarios and produce dependable joints in different applications. |
| Tempoh Latihan | 221 |
| Objektif Pembelajaran | The learning outcomes of this competency are to enable the trainees to perform GMAW process in 1G, 2G, 3G, 4G, 5G and 6G butt weld on carbon steel according to approved Welding Procedure Specification (WPS) and work instruction. Upon completion of this competency unit, trainees should be able to: 1. Carry out GMAW 1G plate butt welding (carbon steel). 2. Carry out GMAW 2G plate butt welding (carbon steel). 3. Carry out GMAW 3G plate butt welding –uphill (carbon steel). 4. Carry out GMAW 4G plate butt welding (carbon steel). 5. Carry out GMAW 5G pipe butt welding – uphill (carbon steel). 6. Carry out GMAW 6G pipe butt welding – uphill (carbon steel). |
| Pra-Syarat | Not Available |