Define the reported property
Ask whether the value is measured, estimated from another property or used as a broad grade descriptor. Retain the method, units and whether it is typical or an agreed limit. Do not turn a catalogue phrase into a contractual test without that explanation.
If solution viscosity is reported, ask for concentration, preparation water, temperature and instrument conditions. A larger number from a different method does not establish a higher-performing product for your suspension.
Check usable stock and application response
Review whether the proposed preparation can be made and delivered with the installed system. A more viscous stock may create a handling constraint even when the product is a promising flocculant. Record concentration changes separately from grade changes.
Compare candidate and reference on representative feed using explicit commercial dose units or a supported common basis. Preserve liquid quality and downstream solids behavior, not only floc size. A headline property does not guarantee survival through every transfer stage.
Agree the purchase evidence
Keep supported analytical requirements separate from the plant qualification record. Ask for the corresponding batch evidence where a critical limit is agreed. If the method is unavailable, identify what information or testing is needed rather than inventing a conversion.
Use the document chain and specification control to carry the accepted basis into supply. A repeated order should reproduce the approved code and relevant methods, not an unsupported statement that the new material is equally high molecular weight.
Keep these purchase records
| Decision | Evidence to retain |
|---|---|
| Property | Measured, estimated or descriptive status and the relevant method are explicit. |
| Operation | Stock delivery and separator evidence support the proposed grade. |
| Order | Agreed methods and qualification remain separate but traceable parts of acceptance. |