Material matching issues for pipes and fittings
Thread Content
In Appendix B of GB/T13401-2017, many material grades correspond to multiple pipe standards; for example, CF415 corresponds to GB3087 and GB8163, while CF415K corresponds to GB6479, GB9948, GB5310, and GB9711. Since the quality grades of different pipeline standards vary, when pipe fittings are selected according to GB13401 in the construction drawings, the quality grade of the steel pipes used as raw materials for those fittings may be lower than the standard specified for the steel pipes used in the drawings. What do everyone think about this issue?
Just ask the design institute directly whether it can be replaced; if not, then we will have to follow the standards specified in the construction drawings. Otherwise, if you replace it without permission, you will be held responsible in case anything goes wrong.
Adhere to principles: it is acceptable for the higher-ranked to guide the lower-ranked, but it is not appropriate for the lower-ranked to guide the higher-ranked
The problem is that the design allows only the use of materials specified by standards, and among those standards, there are multiple raw materials that can be chosen arbitrarily by the manufacturer (as the construction drawings do not specify them); as a result, it is inevitable for lower-quality materials to be used alongside higher-quality ones, which is a legitimate yet unreasonable outcome.