The welding process of copper forgings in construction machinery can generally adopt the following steps:
- Preparation: First of all, clean and remove oil from copper forgings, ensure that the surface of the welding area is clean, and remove cracks or other defects.
- Welding material selection: Choose the welding material suitable for welding copper forgings, commonly used copper wire or silver wire.
- Preheating treatment: For large copper forgings, appropriate preheating treatment is required before welding to reduce thermal stress and cold cracks.
- Welding parameter setting: According to the specific welding materials and welding equipment, set the appropriate welding parameters, including current, voltage, welding speed, etc.
- Welding operation: welding copper forgings according to the set welding parameters. Pay attention to controlling the temperature and time during the welding process to avoid welding defects caused by overheating or undercooling.
- Post-treatment: After the welding is completed, the welding area is slag removal, grinding and other post-treatment work to improve the quality of the weld.
For the analysis of welding defects, there are the following common types:
- Weld cracks: Cracks in the weld may be caused by thermal stress caused by too high welding temperature or too fast cooling speed. The crack can be avoided by controlling welding parameters and preheating treatment reasonably.
- Pores: During the welding process, if there is gas or impurities in the welding area, pores will be formed. The appearance of pores may be caused by the presence of pollutants in the welding area, the welding current is too small, or the welding speed is too fast. The porosity can be avoided by cleaning the welding area and adjusting the welding parameters.
- Slag inclusion: During the welding process, if there is unmelted flux or impurities in the welding area, slag inclusion will be formed. The appearance of slag inclusion may be due to the flux is not completely melted or melted incomplete, welding speed is too fast and other factors. The slag inclusion can be avoided by adjusting welding parameters and selecting flux reasonably.
The above is a general analysis of the welding process and welding defects of copper forgings of construction machinery, which should be adjusted and operated according to the requirements of specific welding materials and welding equipment. At the same time, in the actual welding, you should also pay attention to safe operation, follow the relevant norms and standards, and ensure the quality and safety of welding.
