The chemical composition inspection methods of impeller castings include chemical analysis and spectral analysis. Chemical analysis has high precision and can be used as an arbitration method, but the analysis speed is slow. Although the analytical accuracy of spectral analysis method is slightly lower than that of chemical analysis method, the analysis speed is fast, so this method has been widely used in impeller casting production. Direct reading spectral analysis was used.
Equipment model: xb-7503b photoelectric direct reading spectrum analyzer. Spectral via Ф 20mm。
Standard sample: zg1cr18ni9ti standard sample.
Analysis sample: take samples from the plum blossom test bar. The working surface of the processed spectral analysis sample shall be flat and smooth without pores, sand holes, shrinkage cavities, porosity, burrs, cracks and inclusions. The results of direct reading spectral analysis are listed in the table.
| Element | C | Si | Mn | Cr | Ni | Ti | S | P | Remark |
| Analysis data 1 | 0.080 | 1.0 | 1.5 | 18.0 | 9.0 | 0.62 | 0.026 | 0.032 | Cast sample |
| Analysis data 2 | 0.083 | 1.1 | 1.3 | 18.5 | 10.0 | 0.58 | 0.025 | 0.030 | Cast sample |
| Batching calculation | 0.079 | 0.887 | 1.585 | 18.37 | 10.10 | 0.625 | 0.0175 | 0.0279 | Calculate batching value |
| Standard data | ≤0.12 | ≤1.5 | 0.8-2.0 | 17.0-20.0 | 8.0-11.0 | 0.5-0.7 | ≤0.030 | ≤0.045 | Casting standard (gb2100-80) |
After comparing the results of direct reading spectral analysis with gb2100-80 impeller casting standard, it can be seen that its chemical composition, especially the carbon content, fully meets the requirements, and its impurity element content is lower than the standard specified value, which is basically consistent with the batching calculation, so it meets the chemical composition requirements of impeller casting.