Chemical compatibility must cover every exposed material, including body, segment, seat, shaft, packing, secondary seals and coatings. A stainless body description alone is not enough.
Describe the real mixture
Provide constituents, concentrations and temperature ranges, including contaminants and cleaning chemicals. Trace chlorides or an occasional cleaning step may be more limiting than the main process fluid. If the mixture changes during a batch, identify the different states rather than giving only the final composition.
Avoid generic equivalence assumptions
Cast and wrought material designations do not always mean identical products or properties. Polymer grades, fillers and elastomers vary as well. Ask for an explicit wetted-material schedule and the offered grade names. Corrosion tables can support screening but may not fully represent mixed chemicals, erosion or elevated-temperature exposure.
Build documentation into procurement
Specify material certificates and any verification or corrosion review required for the project. If an alternate material is offered, request a written deviation and technical explanation. Ensure spare seals and replacement trim use the approved material system; an apparently similar replacement can change compatibility.
Practical checklist
- Complete fluid composition and concentration ranges.
- Normal, upset and cleaning temperatures.
- All wetted metallic and non-metallic components.
- Material traceability and accepted substitutions.
Discuss your application
Send the process conditions and required valve function for a configuration review. Request a technical quotation ↗