TPI

TPI is an acronym that can refer to several concepts depending on the domain. Common uses include threads per inch, triosephosphate isomerase, and third-party inspection.

In mechanical engineering and manufacturing, TPI denotes threads per inch, a measure of thread density on fasteners. The TPI value indicates how many threads appear in one inch of the screw or bolt. It affects fit with nuts, taps, and other components, and standards exist for different regions and thread types, such as imperial or metric systems.

In biochemistry, TPI stands for triosephosphate isomerase, an essential enzyme in glycolysis that catalyzes the interconversion of dihydroxyacetone phosphate and glyceraldehyde-3-phosphate. The enzyme is encoded by the TPI1 gene in humans, and defects can lead to metabolic disorders. TPI is widely studied for its role in energy production and cellular metabolism.

In supply chain and quality assurance, TPI refers to third-party inspection, the process of external evaluation of products, processes, or suppliers to verify conformance to specifications and regulatory requirements. Third-party inspections help verify quality, mitigate risk, and support compliance across manufacturing and logistics operations.

In other contexts, TPI can denote additional terms or organizational names, depending on the field and usage. The exact meaning is typically clarified by the surrounding domain or accompanying definitions.