How to understand it in English
Thread Content
In the event of a specification change related to the material, a higher-grade material should be selected for the valve body. In the case of a specification change related to the valve’s capacity, a higher capacity should be chosen for the valve
When the pipeline grade changes, the material and grade of the valve body shall be those corresponding to the higher material and pressure grade.
That’s what I mean; if it doesn’t work, try finding the Chinese version!