Cast iron electrode in the welding and repair welding what characteristic to have?
Publish Time: 2016-11-04 Origin: Site
Cast iron welding rod because of high carbon content, the organization is not uniform, low strength, poor plasticity, belong to the poor weldability of material, process easy to produce crack;Cold after welding speed fast, is easy to produce white tissue caused by machining difficulty.
Cast iron welding and repair welding, to achieve satisfactory results, must pay attention to "three materials, seven parts process", not only want to select electrode, and adopt appropriate repair welding method is particularly important.
Recommend the following welding technology, as a reference when cast iron welding and repair welding:
1.The first welding position of clay, sand, water, dirt, rust, etc;For long-term work under the environment of high temperature, steam iron, and poor surface carbon layer and oxide layer.
2.According to the shape of the welding parts, defect types, open groove, play to measures such as check in and molten pool shape.
3.For cold welding of the workpiece, preheating first around 500-600 ℃, selects the appropriate current and continuous welding, the welding process is always keep the preheating temperature, immediately after welding cover the heat preservation material such as asbestos powder, allow it to cool down slowly, in order to improve its crack resistance and processability.
4.For cold welding workpiece, avoiding excessive parent metal melting, reduce chilling tendency, avoiding excessive heat concentration, cause too much stress, try to use small current, short arc, narrow welding (weld length is generally not more than 50 mm each).Hammer immediately after welding seam with relaxation stress to prevent cracking, when the temperature falls below 60 ℃ welded together.