Sampling valve is a kind of process industry valve, generally used in the production process. It allows to extract a representative part of the fluid (gas, liquid, smiling particulate solids, slurry) in the pipeline for testing (such as physical testing, chemical analysis, microbiological inspection, etc.). Usually used for quality control or regulatory evaluation purposes.

Sampling valves are like human blood sampling instruments, allowing operators to extract product samples from production lines or reactors and store them safely for analysis in the laboratory or to archives for further use.

In a chemical plant, before shipping or accepting chemicals, sampling can be taken during the process to ensure that the output meets specifications (or the quality is acceptable).