Plug Gauge

A plug gauge is a non-graduated special measuring tool used to check whether the size of a hole diameter is acceptable. It usually consists of a go end and a no-go end. In foreign trade, plug gauges are often imported and exported as precision measuring tools and belong to the category of measuring instruments. The HS code is usually 9017.8000. Application scenarios include quality inspection in machining, automobile manufacturing, aerospace, and other fields. Notes: When exporting, confirm the metrological standards of the importing country (such as ISO, DIN, ANSI), and pay attention to calibration certificates, materials (such as tool steel, cemented carbide), and accuracy grades (such as IT6-IT8). Difference from a snap gauge: a plug gauge measures inner diameters, while a snap gauge measures outer diameters. Difference from a ring gauge: a ring gauge is used to inspect external threads or shaft diameters, while a plug gauge is used for internal threads or hole diameters. In foreign trade contracts, specifications, tolerances, surface roughness, and acceptance standards should be clearly specified to avoid disputes caused by differences in measurement units or standards.