Method to solve the corrosion defect of centrifuge

After the warranty period, the centrifuge corrosion defect forms and treatment methods are as follows:
1, spot corrosion, the following three cases, belong to the minor, can be temporarily not treated.
1) pitted corrosion area with large area, but no cracks;
2) scattered corrosion pit points, whose maximum corrosion depth has not exceeded half of the wall thickness required for the calculation of vessel strength (excluding the calculated thickness of corrosion margin);
3) In the scattered pitting zone, there is no serious chain pitting.
2. There are three treatment methods for corrosion defects under a single skin of centrifuge and individual pit corrosion defects with an area of no more than 40mm.
1) Shallow, can be temporarily not processed
2) When it is deep, the grinding method can be adopted, but the wall thickness should meet the strength requirements after grinding;
3) If the strength requirements cannot be met after grinding, surfacing welding should be used.
3. When several large pitting defects with a single area diameter of no more than 40mm of centrifuge exist at the same time, there are two situations.
1) When the spacing between two adjacent defects is greater than 120mm, it can be treated according to individual pit corrosion defects;
2) When the spacing between two adjacent defects is less than 120mm and greater than 50mm, and the corrosion depth does not exceed 60% of the wall thickness, surfacing welding can be used.
4, centrifuge local corrosion defects, its depth does not affect the strength requirements and the area is large (such as large area spots or ulcerative corrosion), can be used metal spraying treatment.
5, centrifuge local uniform corrosion defects, can be treated according to the following three situations.
1) The corrosion area can be large or small, as long as the defect depth does not exceed 40% of the original thickness of the wall, it can be surfacing welding treatment;
2) When several uniform corrosion defects exist at the same time, the area of a single block is not greater than 50mm*50mm, and the spacing between two adjacent corrosion areas is greater than 50mm, and the defect depth does not exceed 60% of the original thickness of the wall, surfacing welding can be used;
3), when the corrosion sheet is too much or too widely distributed, it can be used to dredge or replace the defective cylinder or cylinder.
6, centrifuge comprehensive uniform corrosion defect is one of the least dangerous corrosion defects. Generally only for anti-corrosion measures, do not do other treatment.
7, intergranular corrosion defect is one of the most dangerous defects, for this defect, mainly adopt preventive measures, otherwise produced this defect, can only be replaced as a whole.