Jis B: 7420 Pdf
They require a surface plate (typically granite) that meets the flatness tolerance for Grade 0 as defined in Table 2 of the standard. You will need a calibration certificate referencing that specific grade and standard.
The PDF document (JIS B 7420) is dense with technical data. When you obtain the official copy, you should expect to find:
Many countries have reseller agreements with JSA. These are often more user-friendly for non-Japanese speakers. jis b 7420 pdf
Pro Tip: When purchasing, look for the "English Version." While the numerical tables are universal, the explanatory text and definitions are critical. Do not buy the Japanese-only version unless you are fluent in technical Japanese.
Many engineers ask how JIS B 7420 differs from international equivalents. Here is a quick comparison: They require a surface plate (typically granite) that
| Feature | JIS B 7420 | ISO 8512 | DIN 876 | | :--- | :--- | :--- | :--- | | Geographic Focus | Japan/Asia | Global | Germany/Europe | | Grades | 0, 1, 2 | 0, 1, 2, 3 | 00, 0, 1, 2 | | Flatness Formula | More stringent for smaller plates | Linear with size | Similar to ISO | | Material Preference | Granite & Cast Iron | Granite only | Cast Iron primarily |
Note: JIS B 7420 tolerances are generally tighter than ISO 8512 for plates under 1,000 mm in length. If you are complying with Japanese customer requirements, always default to JIS. Pro Tip: When purchasing, look for the "English Version
Once you have successfully downloaded the official file, follow these best practices:
JIS B 7420 is the Japanese Industrial Standard titled "Plain plug gauges and ring gauges." Specifically, it specifies the nominal sizes, tolerances, and permissible wear limits for cylindrical plain plug gauges (used to check holes) and plain ring gauges (used to check shafts).
This standard is essential for anyone working with:
Avoid these pitfalls:
