GB/T 40802-2021 in English

Analysis of the core content of the standard

GB/T40802-2021, as the technical specification for casting carbon steel and low alloy steel castings in my country, integrates the professional and technical strength of 21 units and makes localized revisions to the ISO14737:2015 standard. The standard is applicable to the production of 21 grades of castings from ZG200380 to ZG32Ni2CrMo, and the technical indicators are more applicable to engineering.

Comparison of key technical requirements

Key indicators of material performance

Implementation suggestions

1. Welding process control: Major weld repairs (>40% wall thickness or 65cm²) need to be recorded and post-weld heat treatment should be performed. The preheating temperature refers to Appendix C
2. Detection scheme optimization: It is recommended to use a combination of spectral analysis + mechanical properties testing, and the wall thickness of the test block should be ≥28mm
3. Quality traceability: It is mandatory to mark the melting furnace number, and it is recommended to use laser marking instead of traditional steel stamping

Standard evolution analysis

The main technical breakthroughs of this standard are: ① Adding domestic specialty grades such as ZG10Mn2MoV; ② Refining the terms of the influence of wall thickness on performance; ③ Supplementing welding process guidance data. Compared with international standards such as ASTM A148, the requirements for purity control of Cr-Mo steel grades are more stringent.