Plain limit gauges. standard by Japanese Industrial Standard / Japanese Standards Association , 01/01/1997. Accuris Standards Store JIS B 7420 - 1997-03-31 - DIN Media
The standard, officially titled "Plain Limit Gauges," is a Japanese Industrial Standard (JIS) that specifies the requirements for dimensional inspection tools used for holes and shafts. It provides the technical basis for ensuring that parts manufactured for machinery and precision equipment fall within their specified tolerance zones. Scope and Application jis b 7420 pdf
: Gauges are typically constructed from durable materials like alloy tool steel (e.g., SKS31) with high hardness (HRC 58–64) to resist wear during repeated inspections. Plain limit gauges
The standard provides specific formulae (found in Table 5 of the document) and attached tables to calculate the exact size of a limit gauge based on the workpiece's nominal size and tolerance grade. When dimensions reach five or more decimal places, they are rounded to four places according to . How to Access the JIS B 7420 PDF It provides the technical basis for ensuring that