Metric internal thread dimensions chart according to ASME B1.13M "Metric Screw Threads: M Profile" standard. Minor diameter, pitch diameter and major diameter are given dimensions in the internal thread chart. All dimensions are in millimeters.
Internal thread (or nut thread) is a term to describe all internal threads in ISO metric thread standards.
Threads produced to ASME B1.13M standard are fully interchangeable with threads that are based on ISO 68-1 basic profile and ISO 965-1 tolerance practices.
Selected Internal Thread Tolerance Classes:
-No-allowance - tolerance class 6H.
Internal threads with allowance are not standard practice.
Standard internal threads provide no allowance for coating thickness. Use the allowance provided by tolerance position G if 4 times the maximum coating thickness specified is equal or less than this allowance. Check ASME B1.13M - 2005 standard for more information.
The designation of a screw thread gives the thread symbol, the nominal size, the pitch, and the thread tolerance class (Ex: M6 x 1 - 5H6H). In internal thread tolerance class designation, the pitch diameter tolerance is followed by minor diameter tolerance. If the two class designations for the pitch diameter and minor diameter are same, it is not necessary to repeat the symbols. (Ex: M6 x 1 - 6H)
General Note: All dimensions are in millimeters.
Note 1: Dimension is used in the design of tools, etc. In dimensioning internal threads it is not normally specified.