A sampling valve is a type of valve used in process industries that allows taking a representative portion of a fluid (gases, liquids, fluidized, solids, or slurries) to test (e.g. by physical measurements, chemical analysis, microbiological examination), typically for the purposes of identification, quality control, or regulatory assessment. It is a valve used for sampling.
The sampling valve allows the operator to extract a sample of the product from the production line or reactor and safely store it for transportation to the laboratory where it will be analysed or to the archive room where it can be retrieved for further use.
In chemical plants, a sample can be taken during the process to ensure that the output meets specifications (or that the quality is acceptable), before shipping the chemical good or before accepting the chemical product.