Visual inspection is not only the first step in the delivery inspection of cast steel joints, but also an essential link. Defects on the outer surface of cast steel joints will seriously affect the use of cast steel joints due to corrosion. Visual inspection can preliminarily detect the outer surface defects of cast steel joints, and then the workers in the steel casting plant can repair or polish these defects. Only two defects, non fusion and shrinkage cavity, were found by visual inspection, and 11 cast steel joints were detected in 24 cast steel joints. As shown in the table, the types and quantity of defects detected by visual inspection in 11 cast steel joints are counted. The distribution and quantity of non fusion defects in cast steel joints are scattered, so only the existence of such defects is counted, but the specific value is not counted. It can be seen from the table that 10 of the 24 cast steel joints have non fusion defects; There are shrinkage defects in zg-06 and zg-08 cast steel joints, and the number of shrinkage defects is 2 and 1 respectively; Only zg-08 cast steel joint has both non fusion defects and shrinkage defects.
| Node number | Incomplete fusion casting defect | Shrinkage casting defect |
| ZG-03 | Yes | / |
| ZG-06 | / | 2 |
| ZG-08 | / | 1 |
| ZG-09 | Yes | / |
| ZG-10 | Yes | / |
| ZG-11 | Yes | / |
| ZG-18 | Yes | / |
| ZG-21 | Yes | / |
| ZG-22 | Yes | / |
| ZG-23 | Yes | / |
| ZG-24 | Yes | / |
After the visual inspection of cast steel joints, the magnetic particle flaw detection of cast steel joints in R zone shall be carried out to detect the surface and near surface defects in R zone. Magnetic particle testing shall refer to the standard GB / t9444-2007 magnetic particle testing of steel castings. A total of 13 cast steel joints in 24 test samples have R-zone. Through magnetic particle flaw detection, it is found that among the 13 cast steel joints with R-zone, 4 cast steel joints have defects in R-zone, and the defects are cracks.